_Hamilton――Ferrier――and Robertson._

SIR WILLIAM HAMILTON,1 the most learned of all the Scottish philosophers, was the son of Dr. William Hamilton, professor of anatomy in the University of Glasgow, a position formerly held by his grandfather, Dr. Thomas Hamilton. Sir William was the lineal representative to the title of Sir Robert Hamilton, the leader of the Covenanting army at Drumclog, and he manifested at least one feature of the spirit of his ancestors――the energy and will to combat when occasion occurred. His father died when he was an infant, but he received an excellent education. He passed through the arts classes at the University of Glasgow, and studied medicine one session at Edinburgh, having intended at first to follow the hereditary profession of the family. But in 1807, having obtained a Snell exhibition, he went to Oxford. There he entered deeply into the study of ancient philosophy, and finally graduated in the highest class. He returned to Scotland in 1811, studied law, and was called to the bar in 1816.

1 Born in 1788; died in 1856.

In 1820, Hamilton became a candidate for the chair of moral philosophy, vacant by the death of Dr. Brown. The contest for the chair was very keen, and finally lay between Hamilton and John Wilson. But Hamilton was a Whig, Wilson a Tory; and as the appointment turned upon political grounds, the majority of the town council of Edinburgh,――the patrons of the chair, voted for Wilson, who accordingly obtained it. It should be observed, however, that neither of the two gentlemen had up to that time published anything which could be referred to as evidence of their special qualifications for the chair of moral philosophy in the University of Edinburgh.1

1 In reality, Wilson was quite out of his element in the chair of moral philosophy. But “the chair of moral philosophy in a Scottish university seems to be elastic in its adaptability. Brown made it a chair of psychology; Ferrier, at St. Andrews, a chair of metaphysics; Wilson made it a chair of rhetoric and Belles Letters. It is true that he treated of the passions, virtues, duties, and so on, but he dealt with them in the concrete, with illustrations from literature.”――Sir A. Grant’s _Story of the University of Edinburgh_, Volume II., pages 345‒346.

The following year Sir William obtained the chair of civil history in the University of Edinburgh, and he entered on his duties with ardour and energy; yet his success was comparatively limited. The salary attached to the chair was only one hundred pounds a year. His wide range of historical knowledge enabled him to handle the subject in a comprehensive and attractive manner, and for some years he had a class of about thirty students. He petitioned the Senatus in 1824 to include his subject in the arts curriculum, but the arts faculty gave him no encouragement. Hamilton then, in 1828, enunciated his views to the Royal Commission, but the commissioners, instead of protecting the chair of history, recommended its abolition. In 1833, when the city became bankrupt, the small salary of the chair ceased to be paid, and Hamilton ceased lecturing.1

1 This chair of civil history continued in an anomalous position, though sometimes held by able men, such as Professor Ferrier and Cosmo Innes, until 1862, when the Executive Commission changed the title of the chair to that of history, and then made the lectures of the professor on constitutional law and history necessary for a degree in law.

In 1836, Dr. Ritchie resigned the chair of logic and metaphysics, which he had held for a period of twenty-eight years, and four candidates entered the field for the vacant office――namely, Sir William Hamilton, Isaac Taylor, Patrick C. Macdougall, and George Combe, the popular phrenologist. It was seen that the real contest would be between the first two candidates; and after a hard struggle, of which the issue seemed doubtful, when the final decision was taken, out of thirty-two votes Hamilton had eighteen――a majority of four. Although then in his forty-eighth year, he entered on his new task with all the emotion and ardour of youth, and threw his heart and intellect into the work.

With his exact method and lofty ideal of philosophical style, he felt much difficulty in deciding on the character of the course of lectures on philosophy which would meet the wants of the young students, and at the same time do justice to the subject; and, after three months of intense thought and reflection, at the opening of the session he had only a few of his lectures written. Thus it happened that his lectures on metaphysics were composed during the first session which he taught. He often sat up nearly all the preceding night preparing his lecture for the next day, with his loving wife by his side acting as his amanuensis. These lectures being composed in such circumstances, and solely designed for the instruction of his own class, it is not surprising that they may not at all points present a consistent and complete exposition of his philosophical views; still, so far as they go, they may be fairly assumed to contain a reliable statement of his chief doctrines. His lectures on logic were composed during the next session, and under the same pressure as the former course.

Hamilton greatly felt the want of text-books suitable for his purposes, so he resolved to edit an edition of Reid’s works, and projected a new work on logic. It has been affirmed by some that the dedication of his powers to the service of Reid was a great mistake, that he should have built entirely upon his own foundation. Be this as it may, the form of exposition which he selected was in some respects unfortunate. His numerous footnotes to Reid’s works were written as the text was passing through the press in 1837 and 1838, and the supplementary dissertations to the end of D were written and stereotyped in 1841 and 1842.

But, in 1838, a quarrel arose between Hamilton and the town council of Edinburgh about his lectures, which had the effect of preventing him from delivering a separate and more advanced course of lectures on metaphysics.1 Then his brother died, to whom he was warmly attached. Next came the threatened disruption of the Church of Scotland, which he struggled hard to avert; and in 1844, in the midst of his arduous labour and duties, a severe paralytic stroke almost deprived him of the use of his right side for the rest of his life. Though he partly recovered, and his mental faculties seemed unimpaired, he never regained his former energy and health.2

1 “It was a loss to the University that Sir W. Hamilton’s separate class in metaphysics was put a stop to; but this was due to his own uncompromising temper, as well as to the somewhat ignorant interference of the town council.”――Sir A. Grant’s _Story of the University of Edinburgh_, Volume II., pages 62‒65. I may add that it was a loss to the nation and to philosophy.

2 Veitch’s _Memoir of Sir W. Hamilton_, pages 266, 270, 278, _et seq._

So when his edition of Reid’s works was issued in 1846, it still remained incomplete; one of his supplementary dissertations breaking off in the middle of a sentence; and although afterwards added to, it was never completed. The fragmentary materials which his editors collected and published, after his death, form but a small portion of what Hamilton originally intended to present; while only an outline of his projected work on logic ever appeared. All hope of revising his lectures seems to have been relinquished, save by occasional oral interpolations. But he continued to lecture and instruct his classes, though sometimes an assistant read his lectures, when the effort of delivery had become too painful for himself. He expired shortly after the close of the session of 1856, tended in his last moments by his faithful wife, and surrounded by his children.

Hamilton was much beloved by his pupils; and all who called on him for information were kindly treated. Although his temper was warm and sometimes easily roused; on the whole, however, his life was a noble struggle; and, if he occasionally manifested an impatience of ignorant opposition, it was only natural and human. Yet, in one or two of his controversies with opponents of his special doctrines, his vehemence passed the limits of fair discussion.

His writings consist of:――1. Sixteen articles contributed to the _Edinburgh Review_, chiefly on philosophy, education, University reform and methods of teaching, and on literature; the first of these appeared in 1829, and he republished the whole of them in 1852, with large additions. 2. His notes and supplementary dissertations to Reid’s works. 3. His lectures on metaphysics. 4. His lectures on logic. All his writings bristle with quotations and references to the views of previous thinkers; his erudition was vast and varied.

In order to give his views the justice to which they are well entitled, and to mark the gratitude for his memory which I warmly feel,1 I will indicate the lines on which his philosophy may be justly appreciated and fairly expounded. The first requisite is to understand the purpose of a writer’s works, and in the case of Hamilton, to take special account of the immediate aims which he had in view; guided by these considerations, I will begin the exposition of his system with his lectures on metaphysics――his psychology, then the philosophy of the conditioned, and close with his logic. The fundamental principles are these:――(1) His peculiar view of the end of speculation; (2) his theory of external perception――natural realism; (3) his doctrine of _a priori_ laws or native notions of the mind; (4) his philosophy of the conditioned; (5) his conception of logic, and the peculiarities of his logical system.

1 I never had the gratification of even seeing Sir W. Hamilton; yet I may be permitted to state, that the first philosophical writings which I ever read with interest was his volume of discussions, which I perused shortly after the date of his death. His edition of Reid soon after came into my hands; and his four volumes of lectures, almost immediately after their publication. And I now gratefully record, that his writings first roused me to think for myself.

In his introductory lectures he explained to the students the utility of philosophy on its subjective and objective sides; its absolute utility viewed simply in itself, and its value viewed in relation to other sciences. He endeavoured to impress their minds with just ideas of the importance of philosophy, and to clear away all superficial misconceptions of the end and objects of education. He discussed philosophy as means and ends in relation to the culture and happiness of man. While man himself, being in so far a mean for the glory of God, “must be an end unto himself, for it is only in the accomplishment of his own perfection that, as a creature, he can manifest the glory of his Creator.... I say it is manifest that man is by nature necessarily an end to himself――that his perfection and happiness constitute the goal of his activity, to which he tends, and ought to tend, when not diverted from this, his general and native destination, by peculiar and accidental circumstances.” In the realities of social life, however, “each man, instead of being solely an end to himself――instead of being able to subordinate everything to that full and harmonious development of his own faculties, in which his real perfection and his true happiness consists――is, in general, compelled to turn himself into the mean towards the accomplishment of some end, external to himself, and for the benefit of others. So the perfection of man as an end, and the perfection of man as a mean or instrument are not only not the same, but in reality they are generally opposed ... even admitting, therefore, that the study of the mind is of no immediate advantage in preparing the student for many of the subordinate parts in the mechanism of society, its utility cannot on that account be called in question, unless it be asserted that man ‘liveth by bread alone,’ and has no higher destination than that of the calling by which he earns his subsistence.”1

1 Volume I., pages 2, 7.

He drew a distinction between the mere possession of truth and intellectual development; by the latter he meant the power acquired through the exercise of the higher faculties of a more varied and vigorous mental activity. This led him to his peculiar view of the end of speculation, and he asks:――“Is truth or is the mental exercise in the pursuit of truth, the superior end? this is perhaps the most curious theoretical, and certainly the most important practical, problem in the whole compass of philosophy. For, according to the solution at which we arrive, must we accord the higher or lower rank to certain great departments of study: and, what is of more importance, the character of its solution, as it determines the aim, regulates from first to last the method which an enlightened science of education must adopt.”

In practical knowledge it is clear that truth is not the ultimate end; as the knowledge of a moral truth, a political, or a religious one, is of value only as it affords the condition of its exercise. But Sir William further held, “that speculative truth is only pursued, and is only held of value, for the sake of intellectual activity.... A truth, once known, falls into comparative insignificance. It is now prized, less on its own account than as opening up new ways to new activity, new suspense, new hopes, new discoveries, new self-gratulation.... Accordingly, the sciences always studied with the keenest interest are those in a state of progress and uncertainty; absolute certainty and absolute completion would be the paralysis of any study....

“But if speculative truth itself be only valuable as a mean of intellectual activity, these studies which determine the faculties to a more vigorous exertion will, in every liberal sense, be better entitled, absolutely, to the name of useful, than those which, with a greater complement of more certain facts, awaken them to a less intense, and consequently a less improving, exercise. It is on this ground that I would rest one of the permanent utilities of mental philosophy.” This doctrine is stated in other parts of his writings;1 and he had sounded the range of its consequences pretty definitely.

1 Volume I., pages 8‒13. In the _Discussions_ he says:――“We exist only as we energise; pleasure is the reflex of unimpeded energy; energy is the mean by which our faculties are developed; and a higher energy the end of which their development proposes.... Speculative truth is subordinate to speculation itself; and its value is directly measured by the quantity of energy it occasions immediately in its discovery, mediately through its consequences” (page 39).

In his opening lecture he told his class that the communication of knowledge was a high, but not the highest, aim of instruction; and that he would not merely deliver lectures――“By all the means in my power I shall endeavour to rouse you, gentlemen, to the free and vigorous exercise of your faculties; and shall deem my task accomplished, not by teaching logic and philosophy, but by teaching to reason and philosophise.”1

1 Volume I., page 18.

In these introductory lectures he also explained the nature and comprehension of philosophy, its causes, and the disposition with which it ought to be studied. Touching the method of philosophy, Hamilton affirms that there is only one possible method――a combination of analysis and synthesis, and the purity and equilibrium of these two elements constitute its perfection.

Concerning the divisions of the philosophy of the mind, he adopted, from Kant, the threefold division of mental phenomena; and the whole subject is enounced in these three questions:――1. What are the facts or phenomena to be observed? 2. What are the laws which regulate these facts, or under which these phenomena appear? 3. What are the real results, not immediately manifested, which these phenomena warrant us in drawing?

First, we should investigate the facts; second, discover their laws; and third, ascertain by legitimate inference their ultimate results. Thus we obtain three branches of mental science, which he designates as phenomenal psychology, nomological psychology, and ontology. Each of these chief classes of the phenomena of mind has a science, which is conversant about its laws. But there is no general science of the cognitive faculties; and the only one of these faculties, whose laws form the object matter of a separate science, is the understanding, the faculty of relations, of thought proper――logic, the science of the laws of thought, in relation to the end which our cognitive faculties propose, that is the true. To this head might be referred universal grammar――philosophical grammar, or the science conversant with the laws of language as the instrument of thought.

The science of the laws of our capacities of enjoyment, in relation to the end which they propose, that is, the pleasurable, has no precise name in English. It has sometimes been called the philosophy of taste, the theory of the fine arts, the science of the beautiful and sublime; and on the Continent it has been termed Æsthetic; but none of these are quite appropriate.

The nomology of our exertive powers and tendencies constitute practical philosophy; for it is simply the science of the laws which regulate our will and desire, in relation to the end which our conative powers propose, that is, the good. This, as it treats these laws in relation to man as an individual, or in relation to man as a member of society, will fall to be divided into two branches――Ethics and Politics; and these again admit of various sub-divisions――such as jurisprudence and legislation.

Empirical psychology is limited to the facts afforded in consciousness, considered exclusively in themselves. But these may be such as not only to be objects of knowledge in themselves, but may also afford us the grounds of inference to something out of themselves. As effects of a peculiar character, they may enable us to infer the analogous character of their unknown causes; as phenomena of particular qualities, they may warrant us in drawing many conclusions regarding the character of that unknown principle, of that unknown substance, of which they are the manifestations. It is true, that the existence of God and the immortality of the soul are not presented to us as phenomena, or as objects of immediate knowledge; still, if the phenomena actually given do inevitably render it requisite, for their rational explanation, then the hypotheses of immortality and of God, we are certainly entitled, from the existence of the former, to infer the reality of the latter. Now, the science which treats of all such inferences of unknown being from its known manifestations, is called ontology, or metaphysics proper.

The following is his tabular view of the distribution of mental philosophy:――

{ Facts,―― { Cognitions. { Phenomenology. { Feelings. { Empirical { Conative Powers { Psychology. { (Will and Desire). { { Mind or { Laws,――Nomology. { Cognitions,――Logic. Consciousness { Rational { Feelings,――Æsthetic. affords. { Psychology. { Conative { Moral Philosophy. { { powers. { Political Philosophy. { { Results,―― { { Ontology. { Being of God. { Inferential { Immortality of the Soul, etc. { Psychology. {

Hamilton considered this distribution of philosophy as the simplest and most exhaustive; and he specially marked out the branches which belonged to his course of instruction.1 In his lectures he treats only one of the three main groups――empiric al psychology――and even this he has not treated exhaustively; only cognitions――the cognitive faculties are fully discussed; but one division of the second group is treated in his lectures on logic. Will and desire receive only incidental notice.

1 Volume I., pages 120‒128. As already mentioned, he originally intended to deliver a more advanced course, and the following sentences, bearing on the point, appear in the manuscript of his seventh lecture:――“The plan which I propose to adopt in the distribution of the course, or rather courses, is the following: I shall commence with mental philosophy, strictly so-called, with the science which is conversant with the manifestations of mind――phenomenology or psychology. I shall then proceed to logic, the science which considers the laws of thought; and finally to ontology, or metaphysics proper, the philosophy of results. Æsthetic, or the theory of the pleasurable, I should consider subsequent to logic, and previously to ontology” (page 128).

A large part of the first volume is occupied with the discussion of Consciousness, which in his system is the primary and fundamental characteristic of mind, and the universal condition of intelligence. He discusses the special conditions of consciousness; its relation to the cognitive faculties; consciousness and attention; the evidence and authority of consciousness; and violations of its authority. Many other interesting questions are discussed, such as the general phenomena of consciousness; whether the mind is always consciously active, or if it is ever unconsciously modified; and an exceedingly interesting lecture on the difficulties and facilities of studying mental science.

While consciousness cannot be logically defined, it may be philosophically analysed. This is effected by observing and holding fast the facts of consciousness, comparing these, and then evolving the universal conditions under which alone an act of consciousness is possible. It is by following this method that we can attain to accurate knowledge of the contents of consciousness.

The nature of the act of consciousness may be shown thus: “When I know, I must know that I know; when I feel, I must know that I feel; when I desire, I must know that I desire. The knowledge, the feeling, the desire, are possible only under the condition of being known by me. For if I did not know that I knew, I would not know; if I did not know that I felt, I would not feel; if I did not know that I desired, I would not desire.... The expressions I know that I know, I know that I feel, I know that I desire, are thus translated by: I am conscious that I know, I am conscious that I feel, I am conscious that I desire. Consciousness is thus, on the one hand, the recognition by the mind of its own acts and affections; in other words, the self-affirmation that certain modifications are known by me, and that these modifications are mine. But, on the other hand, consciousness is not to be viewed as anything different from these modifications themselves, but is, in fact, the general condition of their existence within the sphere of intelligence. Though the simplest act of the mind, consciousness thus expresses a relation subsisting between two terms. These terms are, on the one hand, an I or self, as the subject of a certain modification; and, on the other hand, some modification, state, quality, effection or operation belonging to the subject. Consciousness thus in its simplicity necessarily involves three things: (1) a recognising or knowing subject; (2) a recognised or known modification; and (3) a recognition or knowledge by the subject of the modification.”1

1 Volume I., pages 189, 190‒193.

He explains and illustrates this fundamental characteristic of mind at great length, and with an analytic power and clearness of statement as yet unmatched in the annals of philosophy: “Every mental phenomena may be called a fact of consciousness. But as we distinguish consciousness from the special faculties, though these are all only modifications of consciousness, only branches of which consciousness is the trunk, so we distinguish the special and derivative phenomena of mind from those that are primary and universal, and to give the latter the name of facts of consciousness, as more eminently worthy of that appellation.... A fact of consciousness in this sense is a simple, and, as we regard it, either an ultimate or a primary datum of intelligence. It obtains also various denominations; sometimes it is called a principle, sometimes a fundamental law of mind, sometimes a transcendental condition of thought, etc.” He insists on its characteristics of ultimate priority and necessity; that, as an ultimate fact, it is also given to us with a belief of its reality. It reveals what it is, but not why or how it is. “To ask how any fact of consciousness is possible, is to ask how consciousness itself is possible; and to ask how consciousness is possible, is to ask how an intelligent being like man is possible.... But as we did not create ourselves, and are not even in the secret of our creation, we must take our existence and our knowledge upon trust.”

The result of this inquiry concerning consciousness is――(1) The facts which are given in the act of consciousness itself; and (2) the facts which consciousness does not at once give, but to the reality of which it only bears evidence. As to the first class of facts, no doubt can be or ever has been entertained; it is only the authority of these facts as evidence of something beyond themselves, only thus the second class of facts, which become matter of discussion; it is not the reality of consciousness, but its veracity, that may be questioned.1

1 Volume I., pages 269‒276, _et seq._, and _Discussions_, page 62.

As psychology is only a developed consciousness, a scientific evolution of the facts of which consciousness is the guarantee and revelation; thus the Positive philosopher has a primary presumption in favour of the elements out of which his system is constructed, whilst the sceptical philosopher must be content to argue back to the falsehood of these elements, from the impossibility which the dogmatist may experience in combining them into the harmony of truth. For truth is one, and the end of philosophy is the intuition of unity. He repeated that:――“Philosophy is a systematic evolution of the contents of consciousness by the instrumentality of consciousness; it therefore necessarily supposes in both respects the veracity of consciousness.”1

1 _Discussions_, page 85; _Lectures_, Volume I., page 267.

His theory of attention is stated thus:――“The greater the number of objects to which our consciousness is simultaneously extended, the smaller is the interest with which it is able to consider each, and consequently the less vivid and distinct will be the information it obtains of the several objects. Such being the law, it follows, when our interest in any particular object is excited, and when we wish to obtain all the information concerning it in our power, it behoves us to limit our consideration to that object, to the exclusion of others. This is done by an act of volition or desire, which is called attention. But to view attention as a special act of intelligence, and to distinguish it from consciousness is utterly inapt. Consciousness may be compared to a telescope, attention to the pulling out or in of the tubes in accommodating the focus to the object; and we might with equal justice distinguish in the eye the adjustment of the pupil from the general organ of vision, as in the mind distinguish attention from consciousness as a separate faculty. Not, however, that they are to be accounted the same. Attention is consciousness, and something more. It is consciousness voluntarily applied, under its law of limitations, to some determinate object; it is consciousness concentrated.”

Thus, though attention is not a special and separate faculty of mind, it is an interesting and important subject, and he proceeds to consider it in its various relations, as a general phenomena of consciousness. As to the number of objects which the mind can attend to at once, Stewart supposed that we could only attend to one thing at one and the same instant; but Hamilton supposes that consciousness can simultaneously apprehend six objects. Taking this number of objects as the highest which it can embrace at once, the limitation of consciousness to five, four, three, two, or one, will all be acts of attention, differing only in degree.1

1 Volume I., pages 231‒239, _et seq._

Hamilton rightly holds, that even an act of comparison or discrimination supposes that we are able to comprehend, in the unity of consciousness, the different objects to be discriminated. Instead, therefore, of consciousness not being competent to cognise two things at once, it is only possible under this condition.

He distinguishes three kinds of attention: (1) a mere vital and irresistible act, such as when we open our eyes, we cannot by an act of will avert our mind from all perception of sight; (2) an act determined by desire, which, though involuntary, may be resisted by the will; (3) and an act determined by a deliberate volition. It is the third kind of attention which is really of importance in thinking.

He again refers to the law of limitation in relation to attention, and then says:――“But whatever be its relation to the special faculties, attention doubles all their efficiency, and affords them a power of which they would otherwise be destitute. It is, in fact, as we are at present constituted, the primary condition of their activity.”1

1 Volume I., pages 246‒248, _et seq._ Hamilton gives a clear and interesting explanation of the difficulties of commencing real intellectual efforts, the obstacles that must be overcome before the power of concentrated attention, of continuous thinking, is acquired.

It may not be quite out of character to state briefly my own experience on the subject of attention, or the acquired power of concentration. I admit that Hamilton’s statement of the difficulties of commencing real intellectual efforts is quite true, so far as it goes; yet it appears that in many circumstances, the numerous difficulties which have to be overcome at the initial stages are greater than what he represents them to be. In my own case the initial stage was extremely difficult; the circumstances were unpropitious to the acquisition of the power of concentrating attention, as I was almost constantly in the midst of bustle, and seldom alone. By a prolonged course of persistent efforts, I gradually acquired a complete power of concentrating my mind, by an act of will, upon whatever subject I wished to investigate. This will be understood, when I state that the whole of this history was written, and the proof sheets revised, upon the counter of my own small shop, in the midst of the clattering of a stirring street, and at the same time attending to customers coming in and out. Thus, though often interrupted, I mentally work on, unconscious of noise. The power of attention, of concentration, and of continuous thinking, essentially depends on the strength of the acquired command of the will.

Hamilton’s whole account of attention is exceedingly interesting and valuable, and especially what he says of it in its higher degree, as a direct act of the will, consummated in the habit of deliberate concentration of thought. His view of this, the highest exercise of mind, is as true as it is lucidly expressed.

Among the general phenomena of consciousness, he discusses the question whether we are always consciously active? and begins by averring that there is no pure activity or passivity in creation: that all things in the universe of nature are in a state of continual action and counteraction, being always active and passive at once. “God alone must be thought of as a Being active without any mixture of passivity, as His activity is subject to no limitation. But precisely because it is unlimited, it is for us wholly incomprehensible.”

We are never directly conscious of passivity; so far as we are conscious, we are active; but whether there may be a mental activity of which we are unconscious, is another question. He touches upon the phenomena of dreaming, talking during sleep, and somnambulism, with the view of ascertaining whether the mind be at any moment wholly unconscious. He refers, as usual, to the opinions of other philosophers, but also gives his own personal experience, that the mind remains conscious during sleep.1

1 Volume I., pages 310‒312, 323‒337.

He also discussed the subject of latent mental modifications. He observes, that the possessions of our mind are not to be measured by its present monetary activities, but by the amount of its acquired habits. Thus one knows a science or a language, not merely when he is making a temporary use of it, but inasmuch as he can apply it when and how he pleases, at the command of his will: and so the greater part of our mental treasures lies always behind the sphere of consciousness, hid in the recesses of the mind; this is the first degree of latency. The second degree of latency exists when the mind contains certain systems of knowledge, or habits of action, which it is wholly unconscious of possessing in its ordinary state, but which are revealed to consciousness in certain extraordinary exaltations of its powers. Such as the abnormal states of madness, febrile delirium, somnambulism, catalepsy, etc., when they may flash out into consciousness, and throw into the shade of unconsciousness those other systems by which they had for long been eclipsed and even extinguished. He insists that the theory of latent modifications enables us to account for some of the most perplexing phenomena of mind.1

1 Volume I., pages 339‒352, 366, _et seq._

Sir William’s second volume of lectures commenced with his exposition of the phenomena of cognition; and he classified the special faculties of knowledge thus:――

{ I. Presentative, { External = Perception. { { Internal = Self-consciousness. { { II. Conservative, = Memory. { { III. Reproductive, { Without Will = Suggestion. Cognitive { { With Will = Reminiscence. Faculties. { { IV. Representative, = Imagination. { { V. Elaborative, = Comparison = Faculty of { Relations. { { VI. Regulative, = Reason = Common Sense.

Such is Hamilton’s distribution of the intellectual powers, which he terms the cognitive faculties. He explains distinctly what he meant by a mental faculty,――it is merely a mode of designating a certain class or group of mental energies. In short, all mental powers are only names determined by various orders of mental phenomena; but as these differ from and resemble each other in various ways, various modes of classification may be adopted, and consequently various faculties, in different views, may be the result. “System is only valuable when it is not arbitrarily devised, but arises naturally out of an observation of the facts, and of the whole facts, themselves. On the other hand, to despise system is to despise philosophy; for the end of philosophy is the detection of unity.”1

1 Volume II., pages 3‒5; also footnotes to Reid, pages 221, 242, 511.

1. The presentative faculty on its two sides――perception of external objects, and self-consciousness or reflection, forms the faculty of experience; and it affords us all our contingent knowledge. It enables us to cognise an object, when presented within the sphere of external or internal consciousness; but if our knowledge terminated with this, it would be small indeed. 2. So we have not only a faculty of acquiring knowledge, but also a faculty of retaining it――which is properly called Memory. 3. The reproductive faculty enables us to recall our knowledge out of memory into consciousness; it is the power which regulates the succession of our thoughts, or the laws of mental association. 4. But the general capacity of knowledge renders it requisite that, besides the power of evoking out of unconsciousness one portion of our retained information in preference to another, we have the faculty of representing in consciousness what is thus evoked; and this is effected by the representative faculty, Imagination. 5. The four preceding faculties, or varied acts of acquisition, conservation, reproduction, and representation, form, as it were, a subsidiary class of faculties, furnishing the materials to a higher faculty, which elaborates these; this is the Elaborative faculty, Comparison, or the faculty of relations; and its chief functions are conception, judgment, reasoning, abstraction, and generalisation. 6. The last of the faculties of cognition he called the Regulative faculty――reason or common sense, under which is included all notions, principles, and laws, not derived from experience, but native to the mind, being at once the laws which govern the mind and afford the conditions of its capacity of knowledge.1

1 Volume II., pages 10‒26.

His treatment of perception is somewhat marred by his rather vehement polemic with Dr. Brown; yet his own doctrine may be disentangled from the discussions with which it is mixed up. He is distinguished both as a historian and critic of the theories of perception; but, leaving the historical points as much as possible out of account, his own theory of perception, and his doctrine of Natural Realism, is as follows:――

“The question to be determined is this, Is our perception, or our consciousness of external objects, mediate or immediate?” He gives a general historical account of the views of philosophers touching this subject, discusses and criticises them, with much acuteness and great ability; the objections to natural realism are canvassed; and finally, he takes up the consideration of the general questions of the relation of the senses to the external world, with special reference to the views of Dr. Reid, Stewart, and Dr. Brown. The discussion occupies nearly nine lectures, and the same subject is treated in his Discussions, and in the Supplementary Dissertations to Reid’s works.1

1 I originally intended to present a more detailed account of Hamilton’s views concerning the theories of perception, and other points, but want of space has forced me to relinquish this.

He explains his own doctrine thus: “The only object ever perceived is the object in immediate contact――in immediate relation with the organ. What Reid and philosophers in general call the distant object, is wholly unknown to perception; by reasoning we may connect the object of perception with certain antecedents――certain causes, but these, as the result of inference, cannot be the object of perception. The only objects of perception are in all senses equally immediate. Thus the object of my vision at present is not the paper or letters at a foot from my eye, but the rays of light reflected from these upon the retina. The object of your hearing is not the vibrations of my language, nor the vibrations of the intervening air; but the vibrations determined thereby in the cavity of the internal ear, and in immediate contact with the auditory nerves. In both senses, then, the external object perceived is the last effect of a series of unperceived causes. But to call these unperceived causes the object of perception, and to call the perceived effect, the real object, only the medium of perception, is either a gross error or an unwarranted abuse of language. My conclusion is, therefore, that in all the senses, the external object is in contact with the organ, and thus, in a certain signification, all the senses are only modifications of touch. This is the simple fact, and any other statement of it is either the effect or the cause of misconception.

“In the second place――in relation to the number and consecution of the elementary phenomena――it is, and must be, admitted, on all hands, that perception must be preceded by an impression of the external object on the sense.... On this point there can be no dispute. But the case is different in regard to the two following. It is asserted by philosophers in general: (1) That the impression made on the organ must be propagated to the brain, before a cognition of the object takes place in the mind,――in other words, that an organic action must precede and determine the intellectual action; and (2) That sensation proper precedes perception proper. In regard to the former assertion, if by this were only meant, that the mind does not perceive external objects out of relation to its bodily organs, and that the relation of the object to the organism, as the condition of perception, must, therefore, in the order of nature, be viewed as prior to the cognition of that relation, no objection could be made to the statement. But if it be intended, as it seems to be, that the organic affection precedes in the order of time the intellectual cognition, of this we have no proof whatever. The fact as stated would be inconsistent with the doctrine of an intuitive perception: for, if the organic affection were chronologically prior to the act of knowledge, the immediate perception of an object different from our bodily senses would be impossible, and the external would thus be represented only in the subjective affections of our own organism. It is, therefore, more correct to hold, that the corporeal movement and the mental perception are simultaneous after the bodily has terminated,――in place of holding that the mind is connected with the body only at the central extremity of the nervous system, it is more simple and philosophical to suppose that it is united with the nervous system in its whole extent.”

Touching the latter assertion, that a perception proper is always preceded by a sensation, though maintained by Reid and Stewart, is more erroneous than the former assertion concerning the precedence of an organic to a mental action. In fact, sensation and perception both exist only as they co-exist. “They do not, indeed, co-exist in the same degree of intensity, but they are really equally original; and it is only by an act, not of the easiest abstraction, that we are able to discriminate them scientifically from each other.”1

1 Volume II., pages 185‒189.

The following is a concise statement of his doctrine of Natural Realism:――1. In an act of external perception, “I am conscious of myself as the perceiving subject, and of an external reality as the object perceived, and I am conscious of both existences in the same indivisible moment of intuition. 2. The knowledge of the subject does not precede nor follow the knowledge of the object; neither determines, neither is determined by, the other. 3. The two terms of correlation stand in mutual counterpoise and equal independence; they are given as connected in the synthesis of knowledge, but as contrasted in the antithesis of existence. 4. Consciousness declares our ♦knowledge of material qualities to be intuitive. Nor is the fact, as given, denied even by those who disallow its truth. So clear is the deliverance, that even the philosophers who reject an intuitive perception find it impossible not to admit that their doctrine stands decidedly opposed to the voice of consciousness, and the natural conviction of mankind.” 5. This doctrine of Natural Realism is partly supported upon the distinction of the qualities of matter.1

♦ “knowlege” replaced with “knowledge”

1 _Discussions_, pages 53‒54; also his _Dissertations to Reid’s Works_. In short, his _Dissertations to Reid_ contain a body of valuable philosophical and critical matter relating to the science of the mind. He has endeavoured to present an exhaustive classification of all the possible theories of perception, and his distinctions, explanations, and critical remarks are admirable specimens of logical power and historic genius. This is especially applicable to his important dissertations on the “Qualities of Matter,” of which I had prepared an abstract, and regret that I cannot afford space for it.

Sir William himself says, “that Natural Realism and Absolute Idealism are the only systems worthy of a philosopher; for, as they alone have any foundation in consciousness, so they alone have any consistency in themselves.... The scheme of Natural Realism may be ultimately difficult, for, like all other truths, it ends in the inconceivable; but Hypothetical Realism, in its origin, in its development, in its result, although the favourite scheme of philosophers, is philosophically absurd.”――_Dissertations to Reid_, Note C, page 817.

Having explicated two of the fundamental peculiarities of Hamilton’s system――his view of the end of speculation, and natural realism――I resume the exposition of his views of the cognitive faculties.

Through the powers of internal and external perception, we are enabled to acquire information, experience; but this acquisition is not of itself independent and complete. It supposes that we are also able to retain the knowledge acquired, as we cannot be said to obtain what we are unable to keep. Thus the faculty of acquisition is only realised through the faculty of memory. We have here two distinct elementary phenomena, each depending on the other for its realisation; for without a power of acquisition a power of retention could not be exerted, and without the latter the former would be fruitless, for we should lose as fast as we acquired. Further, the faculty of acquisition would be ineffective without the faculties of reproduction and imagination, for though the mind retained beyond the sphere of consciousness a treasury of knowledge, this would be of no avail, if it did not possess the power of reproducing and representing such knowledge in consciousness. Although the faculty of memory would be fruitless without the faculties of reproduction and imagination, we are not to confound these faculties, or to view the act of mind which is their joint result, as a simple and elementary power; while they mutually depend on each other, the faculties of memory, reproduction, and imagination are governed by different laws, and in different individuals are found to vary greatly in their comparative vigour.1

1 Volume II., pages 205‒207. Further on he says: “By memory, you will see, is only meant the condition of reproduction; and it is, therefore, evident that it is only by an extension of the term, that it can be called a faculty, that is, an active power ... it ought perhaps to receive rather the appellation of a capacity” (page 209).

Touching memory, Hamilton held that all mental energies must persist and endure; we never wholly lose them, but they become obscure. It is only the more vivid changes which sufficiently affect our consciousness to become objects of its apprehension. Thus we are only conscious of the more prominent series of changes in our mental states; the others remain mostly latent. The law of retention extends over all the phenomena of mind. Hence a good memory is one main condition of reproduction.

There is probably no mental power in which such extreme differences appear in individuals as in memory. In a good memory two chief qualities are requisite――the capacity of retention and the power of reproduction.1 To the latter I now proceed.

1 Volume II., pages 211‒218. I may state that at one period I could repeat a sermon or a lecture the morning after hearing it. Although I state the fact of my own experience, I do not at all approve of such stretches of verbal memory, and many years ago I ceased from making any such efforts, and instead cultivated the reproductive and representative faculties.

By the faculty of reproduction, Hamilton meant the process of awakening that which is lying dormant in the memory, as contra-distinguished from the representation of it in consciousness as awakened. He was not satisfied with the term reproductive, because it did not precisely of itself mark what he wished to express. And he was right; for no single term could be chosen which would exactly mark the process and at the same time distinguish it from another closely related process as he wished. “I am not satisfied, I say, with the term reproduction for the process by which the dormant thought or affection is aroused, for it does not clearly denote what it is intended to express....

“The phenomena of reproduction is one of the most wonderful in the whole compass of psychology, and it is one in the explanation of which philosophers have been more successful than in almost any other.... The faculty of reproduction is governed by the laws which regulate the association of the mental train, or, to speak more correctly, reproduction is nothing but the result of these laws. Everyone is conscious of the ceaseless succession of thoughts, one thought suggesting another, which again is the cause of exciting a third, and so on. In what manner, it may be asked, does the presence of any thought determine the introduction of another? Is the train subject to laws, and, if so, by what laws is it regulated?”

He gives, as usual, an indication of the views of other philosophers touching the laws of mental association, and he himself endeavoured to carry up all the laws of association into the “law of redintegration,” which he announced thus:――“Those thoughts suggest each other which had previously constituted parts of the same entire act of cognition. Now, to the same entire or total act belong, as integral or constituent parts, in the first place, those thoughts which arose at the same time, or in immediate consecution; and in the second, those thoughts which are bound up into one by their mutual affinity. Thus, therefore, the two laws of simultaneity and affinity are carried up into unity in the higher law of redintegration of totality; and by this one law the whole phenomena of association may be easily explained.”1

1 Volume II., pages 227‒229, 231‒238. In one of his _Dissertations to Reid_, Hamilton gives a “Contribution towards a history of mental suggestion or association;” this, however, deals chiefly with the views of Aristotle and Themistitus. But he also presents an outline of a “theory of mental reproduction, suggestion, or association,” setting forth his own views. The outline is more developed in thought than what is given in his lectures, but it was left incomplete.

I. In it he distinguishes the general laws of mental succession from those of reproduction proper; and of this class he specifies five laws――1. The law of succession. 2. The law of variation. 3. The law of dependence or determined consecution. 4. The law of relativity or integration. 5. The law of intrinsic or objective relativity; under this head he would also include the law of the conditioned.

II. General laws of mental succession, as of reproduction proper――1. The law of repetition. 2. The law of redintegration. 3. The law of preference.

III. Special laws of mental suggestion――1. The law of similars. 2. The law of contrast. 3. The law of coadjacency.

Herbert Spencer, following some of the lines indicated by Hamilton, insists that the cohering of impressions with previously experienced impressions of the same class is the sole law of association. This is not the only principle which the evolution philosophy has adopted from Sir William’s writings; the cast of Hamilton’s intellect itself was essentially evolutionary.

Hamilton shows that the processes of representation and reproduction are closely related; though they are discriminated by differences quite decisive. Reproduction operates, in part, at least, out of consciousness; while representation is only realised as far as it is realised in consciousness, the vivacity of the representation being always in proportion to the vivacity of our consciousness of its reality. The energies of representation and reproduction are not always exerted by the same individual in equal intensity, any more than the energies of reproduction and retention.1

1 “Some minds are distinguished by a higher power of manifesting one of these phenomena; others for manifesting another; and as it is not always the person who forgets nothing who can most promptly recall what he retains, so neither is it always the person who recalls most easily and correctly who can exhibit what he remembers in the most vivid colours. It is to be recollected, however, that retention, reproduction, and representation, though not in different persons of the same relative vigour, are, however, in the same individuals, all strong or weak in reference to the same class of subjects. For example, if a man’s memory be more peculiarly retentive of words, his verbal reminiscence and imagination will, in like manner, be more particularly energetic.” (Volume II., page 260.)

According to Hamilton’s view of the fundamental processes of the mind, the function of representation is simply the energy of the mind in holding up to its contemplation what it is determined to represent. But he distinguishes as essentially different, the representation, and the determination to represent; for the reproductive faculty is the immediate source whence the representative receives both the material and the determination to represent; and the laws which control the reproductive faculty also control the representative. So if there were no other laws in the combination and construction of thought than those of association, the representative faculty would be solely determined in its manifestation by the reproductive faculty; but comparison――the faculty of relations also comes into operation. Comparison plays an important part in determining in what combinations objects are represented. By its aid, the complex groups of phenomena called up by the representative faculty undergo various operations; they are separated into parts, analysed into elements; and these parts and elements are again compounded and combined in innumerable ways. While in all this, the representative faculty――imagination co-operates; as it first exhibits the facts as called up by the laws of association; it then exhibits them as variously arranged by the analysis and synthesis of the comparative faculty, thus acting as a subsidiary both to the reproductive and elaborative faculties. Still, in these operations the imaginative power is often the most active element in the process; it is a condition of the analytic operations, as it holds up the objects in a vivid light to the analytic grasp, that it may observe the various circumstances of relation, and the new reconstruction――the result of its own elaboration.

A vigorous power of imagination――of representing objects, is indispensable in every department of thought; but there are many kinds and degrees of imagination. There is the imagination of abstraction, representing to us certain phases of an object to the exclusion of others; the imagination of reason, which represents a principle in connection with its consequences, the effect in dependence on its cause; the imagination of feeling, which represents the accessory images allied to some particular sentiment, which thus confer on it greater compass and intensity; the imagination of the passions, and so on.1

1 Volume II., pages 263‒266. Hamilton holds, that the organs which imagination employs in the representation of sensible objects, are the organs of sense themselves, on which the original impressions were made, and through which they were originally perceived. This is the same as Hobbes’ view.

He discusses the elaborative faculty――comparison, or faculty of relations, at length, and in an exceedingly interesting style, under the heads of classification, abstraction, generalisation, judgment, and reasoning. A class of subjects which form the transition from psychology to logic, from the analysis and laws of the mental phenomena, “to the science of thought as thought.” In connection with these, he discusses, in his usual historic form, the interesting subjects of nominalism and conceptionalism, and also the curious question as to “the primum cognitum,” the first cognition, as it was called in the schools. The latter question assumes this character, Does language originate with general names or proper names? Did mankind in the evolution of language, and do children in their first applications of it, begin with general terms or with particular words; or, in other words, does knowledge begin with general notions, or particular notions? There are many illustrious philosophers on each side of the question. Hamilton himself held that our knowledge neither begins with the general nor the particular, but with the vague and confused, and thence proceeds by degrees to evolve both the general and the particular.1

1 Volume II., page 279.

The reduction of complicated processes to greater simplicity, or to a single principle, was a marked feature of Hamilton’s intellect; and the following statement touching comparison is an instance in point. “In opposition to the views hitherto promulgated in regard to comparison, I will show that this faculty is at work in every, the simplest, act of mind; and that from the primary affirmation of existence in an original act of consciousness to the judgment contained in the conclusion of an act of reasoning, every operation is only an evolution of the same elementary process,――that there is a difference in the complexity, none in the nature of the act; in short, that the various products of analysis and synthesis, of abstraction and generalisation, are all merely the results of comparison, and that the operations of conception or simple apprehension, of judgment, and reasoning, are all only acts of comparison, in various applications and degrees.”1

1 Volume II., pages 319, 335.

He proceeds to develop and to prove this view of comparison. The process of classification is simply an act of comparison, determined by the necessities of the mind――the nature and limits of its powers. In classifying, the mind greatly depends on language for its success, on general names, general and abstract terms, which are used to denote complex and abstract notions. Abstraction, or rather exclusive attention to a particular object or quality of an object, is evidently the work of comparison; it is a process quite familiar to the most uncultured minds. Generalisation is dependent on abstraction, and supposes it; but abstraction does not involve generalisation. It is the process through which we obtain general notions and ideas; thus the points in which a number of objects or things agree, having been discovered, we arrange them by these common points of agreement or similarity, into classes; and from the lowest class ascending step by step till we reach at the highest class.1

1 Volume II., pages 279‒283, 293‒295.

Under the last of the special faculties of cognition――the regulative faculty, which is not, properly speaking, an active faculty――he included those primary notions of intelligence or common sense, variously designated as the fundamental principles of intelligence, laws of thought, necessary cognitions, primary data of consciousness. “There are cognitions in the mind which are not contingent,――which are necessary, which we cannot but think, which thought supposes as its fundamental condition. These cognitions, therefore, are not mere generalisations from experience. But if not derived from experience, they must be native to the mind.... These native――these necessary cognitions, are the laws by which the mind is governed in its operations, and which afford the conditions of its capacity of knowledge. These necessary laws, or primary conditions of intelligence, are phenomena of a similar character; and we must, therefore, generalise them or collect them into a class; and on the power possessed by the mind of manifesting these phenomena, we may bestow the name of the Regulative Faculty.”

It should be observed that the primary and necessary notions of the mind here announced as the laws which afford the conditions of knowledge, are embodied by Hamilton in his philosophy of the conditioned. He recognised a considerable number of primary or ultimate notions and principles; but did not pretend to give an exhaustive and complete enumeration of such notions. What he really did, was to argue that there was such a class of notions and principles, and actually employed a certain number of them in the construction of his psychology, his philosophy of the conditioned, and his logic.

With regard to the essential characteristics for discriminating the principles of common sense――the original data of consciousness, he says: “These characters, I think, may be reduced to four: (1) Their incomprehensibility, (2) their simplicity, (3) their necessity and absolute universality, (4) their comparative evidence and certainty.”1

1 Hamilton’s _Reid_, page 754.

What has just been stated, taken in connection with what was said before, of the immediate facts of consciousness, and the intuitive character of perception, will be sufficient to indicate Hamilton’s view of the primary and ultimate notions of the mind. Thus far I have signalised three of the fundamental and distinctive principles of his philosophy. But to complete the exposition of his psychology, it is requisite to notice briefly his treatment of the feelings.

These, the second great class of mental phenomena, in his classification, is not exhaustively treated; but so far it is satisfactory, and exceedingly interesting. He devoted six lectures to the feelings, one of which is occupied with an historical account of the theories of pleasure and pain. His classification and division of the feelings may be indicated thus:

I. First, sensations――the five senses and organic sensations. II. The sentiments and internal feelings: first, the contemplative, subdivided into (1) those of the subsidiary faculties, including those of self-consciousness, and (2) those of imagination, order, symmetry, unity in variety; (3) those of the elaborative faculty, wit, the pleasures of truth and science, and the gratification of adapting means to ends; (4) beauty and sublimity springing from the conjoint energy of the imagination and the understanding. III. The practical feelings relate to (1) self-preservation――hunger and thirst, loathing, sorrow, bodily pain, anxiety, etc.; (2) the enjoyment of our existence; (3) the preservation of the species; (4) the tendency towards development and perfection; and (5) moral law.

He delivered a theory of pleasure and pain, and applied it to explain this general mental phenomena; in other words, he considered the feelings as causes――causes of pleasure and pain; and he then considered them as effects, or products of the action of our different powers. The scope of his standpoint is thus stated by himself:――

“What are the general conditions which determine the existence of pain; for pleasure and pain are the phenomena which constitute the essential attribute of true feeling, under all its manifestations?... I shall, first of all, state the abstract theory of pleasure and pain, in other words, enounce the fundamental law by which these phenomena are governed, in all their manifestations.” Under the ninth and last head of his theory, the following is enounced:――“Pleasure is thus the result of certain harmonious relations――of certain agreements; pain, on the contrary, the effect of certain unharmonious relations――of certain disagreements. The pleasurable is, therefore, not inappropriately called the agreeable; the painful, the disagreeable; and in conformity to this doctrine, pleasure and pain, may be thus defined:――Pleasure is a reflex of the spontaneous and unimpeded exertion of a power, of whose energy we are conscious. Pain a reflex of the overstrained or repressed exertion of such a power.” As already stated, he illustrates the application of his theory in the explanation of pleasure and pain at some length,1 with keen insight and rare breadth of view. In the two last lectures, he treats the feelings as effects――as products of the action of our different powers; and thus considered, his exposition is often very happy.

1 Volume II., pages 434‒440, _et seq._

Hamilton’s Philosophy of the Conditioned is simply an attempt to systematise the conditions of the thinkable, in the form of an Alphabet of human thought. In its fundamental conception it is restrictive and conservative. Probably he was as well informed and aware of the many aberrations of human thought and speculation as any man that ever lived; and he was fully cognisant of the systems and speculations of those philosophers who had pretended to walk through the dark mountains of eternity and infinity without stumbling, and to return with positive knowledge. Knowing this, he was, therefore, well entitled to make an effort to lay down the conditions and limits of human thought; and thus he has done great service to real philosophy, to science, and mankind.

He grounded his own theory of the Conditioned upon the recognised laws of identity, non-contradiction, excluded middle, and the law of relativity. Thus when he speaks of the Conditioned it is in special reference to relativity; and by existence conditioned is meant existence thought under relation. Relation may be understood to contain all the categories and forms of positive thought. We should not, however, think it as a law of things, but simply as a law of thought; for we find that there are contradictory opposites, one of which, by the rule of Excluded Middle, must be true, but neither of which can be positively thought, as possible. Thinking, under this condition, is synthetic. The condition of Relativity is brought to bear under three principal relations: the first springs from the subject of knowledge――the mind thinking, the relation of knowledge; the second and third from the object of knowledge――the thing thought about, the relations of Existence.

1. The relations of knowledge are those arising from the reciprocal dependence of the subject and of the object of thought, self and not-self――subjective and objective. Everything that comes into consciousness is thought by us, either as belonging to the mental self exclusively, or as belonging to the not-self exclusively, or as belonging partly to both.

2. The relations of Existence arising from the object of knowledge are twofold; as the relation is either Intrinsic or Extrinsic. As the relation of Existence is Intrinsic, it is that of Substance and Quality. It may be called qualitative. But, as the relation of Existence is Extrinsic, it is threefold; and as formed by three kinds of quantity, it may be called quantitative. It is realised in or by: (1) Protensive quantity, or time; (2) Extensive quantity, Extension or Space; (3) Intensive quantity, or degree.

3. Time, or protensive quantity, called also Duration, is a necessary condition of thought; and it may be considered both in itself and in the things which it contains.

Considered in itself, Time is positively inconceivable, if we attempt to construe it in thought; on the one side, as absolutely commencing or absolutely terminating, or on the other, as infinite or eternal. It is positively conceivable, if conceived as an indefinite past, present, or future; and as an indeterminate mean between the two unthinkable extremes of an absolute least and an infinite divisibility: for thus it is relative.

Things in Time are either coinclusive or coexclusive. Things coinclusive, if of the same time, are identical, apparently and in thought; if of different times, as causes and effect, they appear as different, but are thought as identical. Things coexclusive are mutually either prior and posterior, or contemporaneous.

The impossibility we experience of thinking as non-existent, non-existent, consequently, in time, aught which we have conceived as existent,――this impossibility affords the principle of Causality, which will be subsequently explained.

Time applies to both Substance and Quantity; and includes the other quantities, Space and Degree.

4. Space, extension or extensive quantity, is likewise a necessary condition of thought; and may also be considered, both in itself and in the things which it contains.

Considered in itself, Space is positively inconceivable: as a whole, either infinitely unbounded, or absolutely bounded; as a part, either infinitely divisible, or absolutely indivisible. Space is positively conceivable, as a mean between these extremes; that is, we can think it either as an indefinite whole, or as an indefinite part. For thus it is relative.1 So much touching the foundation of the philosophy of the Conditioned.

1 _Discussions_, pages 577‒582.

He enounced the Law of the Conditioned thus:――“All positive thought lies between two extremes, neither of which we can conceive as possible, and yet, as mutually contradictory, the one or the other must necessarily be true.”1 We have already seen that we cannot think past time as beginning to be; on the other hand, we cannot conceive it going backwards without limit――eternity baffles our imagination. But time either had a beginning or it had not. So of space, we are unable to conceive space as finite or bounded; we are equally powerless to realise in thought an idea of infinite space. “You may launch out in thought beyond the solar walk, you may traverse in fancy over the universe of matter, and rise from sphere to sphere in the regions of empty space, until imagination sinks exhausted;――with all this what have you done? You have never got beyond the finite, you have attained at best only to the indefinite, and the indefinite, however expanded, is still always the finite.... The infinite is infinitely incomprehensible.” Thus the conceivable or the thinkable “lies always between two inconceivable extremes, as illustrated by every other relation of thought.”2

1 _Discussions_, page 591; also Reid’s _Works_, page 911. Hamilton states the Law of the Conditioned repeatedly in his different writings; and some of its positions are stated at greatest length in the second volume of his _Lectures_.

2 _Discussions_, page 591; _Lectures_, Volume II., pages 366‒372.

The chief applications of the Law of the Conditioned are to the principles of substance and causality: and taking substance first, which he has not treated with much detail. We cannot think a quality existing entirely in or of itself. We are constrained to think it as inhering in some substance; but this substance is only conceived by us the unapparent――the inconceivable correlative of certain appearing qualities. If we attempt to think it positively, we only think it by transforming it into a quality or bundle of qualities, which again we refer to an unknown substance, now supposed for their incognisable basis. Thus, everything may be conceived as the quality, or as the substance of something else; but absolute substance and absolute quality are both inconceivable.1

1 _Discussions_, page 580.

The phenomenon of causality is the Law of the Conditioned applied to a thing thought as existing in time. We cannot know, nor think a thing, except under the attribute of existence, and existing in time; and we cannot know or think a thing to exist in time, and think it absolutely to commence. This imposes on us the judgment of causality. An object is given to us by our perceptive faculties, as given, we cannot but think it existent, and existent in time; but to say this, is to say, that we are unable to think it non-existent,――to annihilate it in thought, and this we cannot do; for once thinking it to exist, we cannot think it not to exist. This will be admitted of the present, but probably denied of the past and future, under the belief that we can think creation or annihilation. Matter or objects may change their forms in innumerable ways; but we cannot conceive that there can be an atom absolutely added to, or taken away from, existence as a whole. Let us try it:――

“We are able to conceive the creation of a world; this indeed as easily as the creation of an atom. But what is our thought of creation? It is not a thought of the mere springing of nothing into something. On the contrary creation is conceived, and is by us conceivable, only as the evolution of existence from possibility into actuality, by the fiat of the Deity. Let us place ourselves in imagination at its very crisis. Now, can we construe it to thought, that the moment after the universe flashed into material reality, into manifest being, that there was a larger complement of existence in the universe and its author together, than the moment before there subsisted in the Deity alone? This we are unable to imagine. And what is true of our concept of creation, holds of our concept of annihilation. We can think no real annihilation, no absolute sinking of something into nothing. But, as creation is cogitable by us, only as a putting forth of divine power, so is annihilation by us only conceivable as a withdrawal of that same power.... In short, it is impossible for the human mind to think what it thinks existent, lapsing into non-existence, either in time past or in time future.”1

1 _Discussions_, pages 591‒593; _Lectures_, Volume II. pages 400‒406.

He thinks that his theory of causality is preferable to others, because to explain the phenomenon of the causal judgment, it postulates no new or express principle, not even a positive power; while it shows that the phenomenon is only one of a class, it assigns as their common cause, only a negative impotence. He also thinks that it affords a philosophical defence of the freedom of the will. He points out the inconsistencies and contradictions of his predecessors; but he admits that speculatively we are unable to understand how moral liberty is possible in man. But practically, our consciousness of the moral law gives a decisive preponderance to the doctrine of freedom over the doctrine of fate. We are free in act, if we are accountable for our actions. That the philosophy of the Conditioned has a real foundation in the human mind, appears to be evident, when considered in its relation to the universe. The necessities of its capacities and faculties of knowledge, their limits and imperfection, as well as the actual position in which man finds himself in the universe of nature, all plainly indicate that his powers of knowledge are anything rather than absolute and infinite. This much may be averred; still, it is open to anyone to question, if Hamilton’s applications of his own theory were in all points the most legitimate. I will now proceed to his logic.

He viewed Logic as a formal science, and divided it into pure and modified. In his lectures on this subject, he proceeds on a definite and interesting style of exposition; he first states the leading doctrines in separate paragraphs, and then in a running commentary explains and illustrates them. The first paragraph is this:――“A system of logical instruction consists of two parts――(1) Of an introduction to the science; (2) of a body of doctrine constituting the science itself.” These he discussed in their order: the introduction to logic should afford answers to the five following questions: What is logic? what is its value? what are its divisions? what is its history? what are the best books on the subject? These questions are treated in a concise and animated style; and the answer to the first one is given in his definition of logic, which is this:――“Logic is the Science of Thought as thought.” But he says that this definition cannot be understood without a clear exposition of its several parts, which he proceeds to present.

What he meant by “the laws of thought as thought,” is thus explained: the term thought is used in two significations, in a wider, and in a narrower and stricter sense, and it is with thought in the latter sense――thought proper, that logic is concerned. “All thought is a comparison, a recognition of similarity or difference; a conjunction or disjunction, in other words, a synthesis or analysis of its objects.... But thought simply is still too undetermined; the proper object of logic is something still more definite; it is not thought in general, but thought considered merely as thought, of which this science takes cognisance.... What is meant by thought as thought? It is the recognition of a thing as coming under a concept; in other words, the marking an object by an attribute or attributes previously known as common to sundry objects, and to which we have accordingly given a general name. Logic is properly conversant with the form of thought to the exclusion of the matter.

“But the limitation of the object――matter of logic to the form of thought, is not yet enough to determine its province from that of other mental sciences; for psychology is, in like manner, among other mental phenomena, conversant about the phenomena of formal thought. A still further limitation is, therefore, requisite; and this is given in saying, that logic is the science not merely of thought as thought, but the laws of thought as thought, ... or the science of the formal laws of thought, or the science of the laws of the form of thought; these being three various expressions of the same thing.”1

1 _Lectures_, Volume III., pages 3‒26.

He gives further explanations, of which this is one:――“Abstract logic considers the laws of thought as potentially applicable to the objects of all arts and sciences, but as not actually applicable to those of any; concrete logic considers these laws in their actual and immediate application to the object-matter of this or that particular art or science. The former of these is one, and alone belongs to philosophy, whereas the latter is as multiform as the arts and sciences to which it is relative.”1

1 Volume III., page 53.

Abstract logic is divided into pure and modified; and the former he divides into two parts: (1) The Doctrine of Elements, which are either laws or products; and (2) Methodology, or the doctrine of Method――the means of thinking well. Modified logic falls into three parts: (1) The first treats of the nature of Truth and Error, and of the higher laws for their discrimination; (2) the second of the Impediments to thinking, with the means of their removal; (3) the third of the Aids of thinking.

In passing, I may remark that Hamilton’s treatment of modified logic, although not exhaustive, is exceedingly clear and valuable so far as it goes. This part of his lectures should be attentively read by those who wish to cultivate their minds, or to study the laws of criticism and historical evidence.

The following is his tabular view of the divisions of logic:

{ { i. Doctrine { 1. Noetic: Nomology. { { of Elements. { { { { 2. Dianoetic: { a. Conception. { { { Dynamic. { b. Judgment. { I. Pure. { { { c. Reasoning. { { { { ii. { Clear thinking: 1. Definition. General { { Method- { Distinct thinking: 2. Division. or { { ology. { Connected thinking: 3. Probation. Abstract { Logic. { { i. Truth and Error: Certainty and Illusion. { { { { ii. Impediments { 1. The Mind. { { to thinking, { 2. The Body. { II. Mod- { with { 3. External circumstances. { ified. { { { iii. Aids or { 1. The Acquisition { { Subsidiaries { of Knowledge. { { to thinking, { 2. The Communication { { through { of Knowledge.

After stating the fundamental laws of thought, he proceeds to the doctrine of Elements――to the exposition of concepts, judgment, and reasoning. Five lectures are given to an explication of concepts or notions: (1) Their general character is described; (2) then their special objective relation, in regard to quantity; (3) their subjective relation, in regard to quality; (4) their imperfection; (5) their reciprocal relation, in regard to the quality of extension ――subordination and co-ordination; (6) their reciprocal relations in regard to the quantity of comprehension, which are all explained with remarkable clearness.1

1 Volume III., page 137, _et seq._

He expounds his doctrine of judgments in two lectures, and it is in connection with the quantification of the predicate of propositions or judgments that Sir William claims to have made improvements on formal logic.1 I am aware that his claim, even on this point, has been disputed since his death, but my limits will not permit me to enter into a discussion of the subject; yet I think that the varied materials printed in the second volume of his _Lectures on Logic_ afford the means of placing it in its true light. Hamilton there notices many partial anticipations of this doctrine.

1 In a footnote to his article on Logic, he says:――“It will be seen from the tenor of the text, that, by the year 1833, I had become aware of the error in the doctrine of Aristotle and the logicians, which maintains that the predicate in affirmative propositions could only be formally quantified as particular, nay, that Aristotle, in his practice in the inductive syllogism, virtually contradicts the speculative precept which he, over and over, expressly enounces for syllogism in general.... The doctrine of a thorough-going quantification of the predicate, with its results, I have, however, publicly taught since the year 1840, at the latest.” ――_Discussions_, page 162.

As already stated, his projected work on logic was never finished. He introduced, however, several modifications in syllogistic theory, and signalised various distinctions, tending toward more simplicity, and constructed an ingenious scheme of logical notation.1 There can be no doubt that he spent a considerable part of his life in prosecuting inquiries connected with logic.

1 See _Discussions_, pages 614‒620, and the appendices to the second volume of his _Lectures on Logic_. His final scheme of logical notation is inserted at the end of this volume. I can only notice a few points:――

1. “That we can only rationally deal with what we already understand, determines the simple logical postulate――to state explicitly what is thought implicitly.

2. “All mediate inference is one――that incorrectly called Categorical; for the Conjunctive and Disjunctive forms of hypothetical reasoning are reducible to immediate inferences.

“Mentally one, the Categorical Syllogism, according to its order of enouncement, is either Analytic (A) or Synthetic (B). Analytic, if what is inappropriately styled the conclusion be expressed first, and what are inappropriately styled the premisses be then stated as its reasons. Synthetic, if the premisses precede, and, as it were, effectuate the conclusion. These general forms of syllogism can with ease be distinguished by a competent notation; and every special variety in the one has its corresponding variety in the other.

“Taking the syllogism under the latter form (B), which, though perhaps less natural, has been alone cultivated by logicians, and to which therefore, exclusively all logical nomenclature is relative,――the syllogism is again divided into the non-figured (a) and figured (b).”――_Discussions_, pages 614‒616.

3. “Quantity and quality combined constitute the only real discrimination of syllogistic mood. Syllogistic figure vanishes, with its perplexing apparatus of special rules; and even the general laws of syllogism proper are reduced to a single compendious canon....

“We have shown that a judgment or proposition is only a comparison resulting in a congruence, an equation, or non-equation of two notions in the quantity of extension; and that these compared notions stand to each other, as the one subject and the other predicate, as both the subject, or as both the predicate of the judgment. If this be true, the transposition of the terms of a proposition sinks into a very easy and a very simple process; whilst the whole doctrine of logical conversion is superseded as operose and imperfect, as useless and erroneous.”――_Lectures_, Volume IV., Appendix, pages 275‒276.

He also wrote very effectively on Education, chiefly on the higher branches, and in reference to University reform. His views were comprehensive, enlightened, and liberal, far in advance of his time. But occasionally he was extremely outspoken and severe on the prevailing abuses and shortcomings of the Universities. He did not limit himself to Scotland, but wrote powerfully on the state of the English Universities, with especial reference to Oxford. He argued that dissenters ought to be admitted into the public Universities. Altogether, his articles on education contain a body of varied, curious, interesting, and valuable information.

To sum up, I have presented a brief account of Hamilton’s psychology and philosophy; its fundamental principles have been explained. He taught the doctrine that man, in so far as he is a mean for the glory of God, must be an end to himself, inasmuch as his perfection and happiness constitute the goal of his activity. He seemed to value the pursuit of truth more than its possession, or rather that its pursuit afforded man more pleasure than its possession, which is quite true. He embraced the doctrine of intuitive perception――natural realism; and drew up a scheme of all the possible theories of perception. He maintained that the human mind possesses native notions, necessary cognitions, which afford the requisite conditions of knowledge. His own vast and varied knowledge of recorded thought and philosophical systems afforded him innumerable instances of the aberrations of thought, contradictions, and vain presumptions; and so he constructed his Philosophy of the Conditioned, which indicates the limits of human thought. He took a strictly formal and limited view of the province of logic; and upon this conception his exposition of the science is clear and masterly. He also endeavoured to simplify the common syllogistic system, and introduced several useful improvements.

His conception of method, his skill and care in arrangement, and in brief and clear summaries, are admirable; while his powers of exposition were of the highest order. The style of his lectures is lighted with a fire and glow of thought and a genuine human feeling rarely found in philosophical literature.

Hamilton attained a European reputation in his own lifetime, chiefly through his articles in the _Edinburgh Review_, and his teaching in the University of Edinburgh. Since his death his writings have had a considerable influence. He had of course a certain number of direct followers, very few of whom are now alive. But several other schools of thought are indebted to Hamilton; and perhaps Herbert Spencer is more indebted to him for the fundamental conceptions and principles of his system of philosophy than to any other philosopher. This of course, mainly refers to Spencer’s _First Principles_, but partly also to his _Psychology_. On the other hand, Hamilton’s philosophy has been subjected to severe criticism from various quarters.1 I can, however, only mention the fact, and must refrain from entering into any discussion.

1 J. S. Mill’s _Examination of Hamilton’s Philosophy_ is well known, and it is an able and acute work; but I affirm that Mill did not, in all respects, present a fair and just estimate of Hamilton. He did not take any account of the circumstances in which Hamilton was placed; and so when reckoning up the little that Hamilton had produced in philosophy in comparison to what he might have done, and began to seek for reasons to explain this, it never occurred to him to assign any weight to these circumstances. Unfortunately Hamilton’s father died when he was an infant; Mill’s father not only lived to bring him up, but also to educate him personally, and to cram him with all kinds of knowledge and science, so that long ere he reached the years of manhood, he was a prodigy; then, when he came of age, his father got him into a position in the Indian Office, where he had only to work a few hours a day. Thus his father did everything for him that could be done. Mill never knew the difficulties of finding a post for himself, or the humiliation of going about seeking employment. Hamilton had to face a very different career, as he had to struggle hard for existence, and fight many a battle ere he attained a position.

But Mill himself avows that he wrote his _Examination of Hamilton’s Philosophy_ for the express purpose of reducing his too great reputation, and explicitly declares in his own _Autobiography_ that it had fully effected its original aim!

Dr. J. F. Ferrier was an intimate friend of Sir William Hamilton, and at one time he was professor of civil history in the University of Edinburgh; but in 1846 he was appointed to the chair of moral philosophy in the University of St. Andrews, which he held until his death in 1864. When the chair of logic and metaphysics in the University of Edinburgh became vacant on the death of Hamilton, Ferrier entered the field as a candidate for it, but he was not successful. However, in connection with this he published a pamphlet in 1856, entitled _Scottish Philosophy, the Old and the New_, the new being his own. In this pamphlet he complained against the town council of Edinburgh for allowing themselves to be influenced by certain outside parties in favour of candidates who professed to teach the old Scottish philosophy in preference to the new. It seems that he was greatly disappointed when he failed to obtain the Edinburgh chair.1

1 In this pamphlet he replied to criticisms on his own metaphysics, and says:――“It has been asserted that my philosophy is of German origin and complexion. A broader fabrication than that never dropped from human lips or dribbled from the point of pen. My philosophy is Scottish to the very core; it is national in every fibre and articulation of its frame. It is a natural growth of old Scotland’s soil, and has drunk in no nourishment from any other land.” (page 12).

Ferrier’s _Institutes of Metaphysics, the Theory of Knowing and Being_, appeared in 1854. It consists of an introduction, partly historical and partly critical, and three sections, the first of which treats of the theory of knowledge, the second of the theory of ignorance, and the third of the theory of being. He adopted the demonstrative method of exposition, states his propositions and counter propositions in a series, and reasons them out in a precise and rigorous form. His thinking is acute, definite, vigorous, and easily followed. In short, his style is unusually clear, simple, and concise.

Ferrier’s first proposition is headed, “The primary law or condition of knowledge,” and it is worded thus:――“Along with whatever any intelligence knows it must, as the ground or condition of its knowledge, have some cognisance of itself.” This is a very primitive truth, and he tells us over and over that it is the keystone of his system. “Looked at in itself, or as an isolated truth, our first proposition is of no importance; but viewed as the foundation of the whole system, and as the single staple on which all the truths subsequently to be advanced depend, it cannot be too strongly insisted on or too fully elucidated. Everything hinges on the stability which can be given to this proposition, on the acceptance it may meet with. If it falls, the system entirely fails; if it stands, the system entirely succeeds. It is to be hoped that the reader will not be stopped or discouraged by the apparent truism which it involves. He may think that if the main truth which this philosophy has to tell him is that all his cognitions and perceptions are known by him to be his own, he will have very little to thank it for. Let him go on and see what follows.”

He remarks that if this first proposition is not very clearly confirmed by experience, it is not refuted by experience; for by no effort can anyone ever apprehend a thing to the entire exclusion of himself. A man cannot leave himself altogether out of his account and proceed to the consideration of the surrounding objects. But experience can only establish it as a limited matter of fact, and this is insufficient for the purposes of his subsequent demonstrations. “It is reason alone that can give to this proposition the certainty and extension which are required to render it a sure foundation for all that is to follow.... It must be established as a necessary truth of reason――as a law binding on intelligence universally――as a conception the opposite of which is a contradiction and an absurdity.

“Strictly speaking, the proposition cannot be demonstrated, because, being itself the absolute starting point, it cannot be deduced from any antecedent data; but it may be explained in such a way as to leave no doubt as to its axiomatic character. It claims all the stringency of a geometrical axiom, and its claims, it is conceived, are irresistible.... A man has knowledge, and is cognisant of perceptions only when he brings them home to himself. If he were not aware that they were his, he could not be aware of them at all. Can I know without knowing that it is I who know? No, truly. But if a man in knowing anything, must always know that he knows it, he must always be self-conscious.”

But this had been fully recognised before by the Scottish School. For there is nothing more explicit in Hamilton, than that consciousness is the primary, the necessary, and the universal condition of knowing, and of knowledge. It would be unfair, however, to adduce this as detracting in any way from the candour and the merit of Ferrier’s work; and I shall quote a part of what he says regarding anticipations of his own first proposition:――

“But passing over all intermediate approximations, we find anticipations of this first principle in the writings of the philosophers of Germany. It has no claim to novelty, however novel may be the uses to which these institutes apply it. Kant had glimpses of the truth; but his remarks are confused in the extreme, in regard to what he calls the analytic and synthetic of consciousness. This is one of the few places in his works from which no meaning can be extracted. In his hands the principle answered no purpose at all. It died in the act of being born, and was buried under a mass of subordinate considerations before it can be said to have even breathed. Fichte got hold of it, and lost it; got hold of it, and lost it again, through a series of eight or ten different publications, in which the truth slips through his fingers when it seems just on the point of being turned to some account. Schelling promised magnificent operations in the heyday of his youth, on a basis very similar to that laid down in this first proposition. But the world has been waiting for the fulfilment of these promises――for the fruits of that exuberant blossom――during a period of more than fifty years.... Hegel――but who has ever yet uttered one intelligible word about Hegel? Not any of his countrymen, not any foreigner――seldom even himself. With peaks, here and there, more lucent than the sun, his intervals are filled with a sea of darkness, unnavigable by the aid of any compass, and an atmosphere or rather vacuum, in which no human intellect can breathe. Hegel had better not be meddled with just at present. It is impossible to say to what extent this proposition coincides, or does not coincide, with his opinions; for whatever truth there may be in Hegel, it is certain that his meaning cannot be wrung from him by any amount of mere reading, any more than the whisky which is in bread――so at least we have been informed――can be extracted by squeezing the loaf into a tumbler. He requires to be distilled, as all philosophers do, more or less, but Hegel to an extent which is unparalleled.”1

1 Pages 82‒84, 90‒92. Since the above passage was written, a considerable change has occurred in Scotland with regard to Hegel. Dr. Stirling’s efforts to explain Hegel are well known; and Dr. Seth, now Professor of Logic and Metaphysics in the University of Edinburgh, after criticising the principle of the Relativity of Knowledge, and generally commenting unfavourably on Hamilton’s principles, speaks of Hegel thus:――

“So far as I can see, Hegel alone of all metaphysicians lifts us completely clear of Relativism. He alone has gone systematically to work to lay bare the abstractions on which it depends; and in so doing he has to a great extent transformed the character of metaphysics, and so rendered unjust many of the epithets which popular phraseology still associates with the science.

“We have Hegel’s own word for it that the method is nothing, unless we bring the whole nature of thought with us.... The Method sums up a thought which may almost be said to constitute Hegel’s philosophy, and one which, in my opinion, gives him a signal advantage over all his modern predecessors.

“The thought in question is primarily a logical principle; a fact which may partly explain why Hegel made his logic the centre of his system. It is the principle to which we have already referred so often, the systematic recognition of the fact that thought is founded upon difference; whereas identity had hitherto been the god of the logician’s idolatry.... I do believe that here we have a principle, not of arbitrary invention, but drawn from the heart of things, from the nature of the self-conscious spirit itself.... The essential point in a systematic philosophy is simply the possession of some outline or scheme, by reference to which each conception may be judged and receive its place and meaning. In self-consciousness, Hegel seems to hold a position, from which, in the nature of the case, it is impossible to dislodge him.”――Seth’s _Lectures on Scottish Philosophy_, pages 167, 171, 174, ♦183, 195‒197.

♦ “83” replaced with “183”

His theory of Ignorance seems the most effective section of his _Institutes_. Its principle is that ignorance is a defect, privation, or shortcoming; and that there can be an ignorance only of that which can be known. But Ferrier’s _Institutes_, and also several dissertations published after his death, are almost entirely occupied in clearing the ground of prevailing contradictions and inconsistencies of thought. His own positive views consist of a few remarks and brief indications.

George Croom Robertson was born in Aberdeen on the 10th of March, 1842. He was educated at the Grammar School there, and at the University of Aberdeen, where, after a very distinguished career, he graduated in 1861 with highest honours in classics and mental philosophy. The same year he gained the Ferguson Scholarship, in these two subjects, one of the great prizes open to all Scottish graduates. Subsequent to this Mr. Robertson pursued his philosophic studies for upwards of two years at Heidelberg, Berlin, Göttingen, and Paris, where he made the acquaintance of Trendeleburg, Du Bois, Reymond, Bona Meyer, Lotze, and other distinguished teachers and thinkers, and profited greatly by their instruction and intercourse. He returned to Aberdeen in 1863, and continued to devote his attention to philosophical study.

Having elaborated a number of valuable and interesting notes from his German studies, he assisted Dr. Bain in the revision and amplification of his work, entitled, _The Senses and the Intellect, the Emotions and the Will_, for a second edition. He also aided Dr. Bain in the ethical part of the excellent manual――_Mental and Moral Science_, and contributed to it the articles on the Neo-Platonists, the Scholastic Ethics, Hobbes, Cumberland, Cudworth, Kant, Cousin, and Jouffroy. In these there is ample evidence of Robertson’s philosophic, critical, and literary powers, scholarship, and research.

In 1864 he was appointed assistant to Professor Geddes in the University of Aberdeen, and held the post for two sessions; he also assisted in teaching the Greek classes. In December, 1866, he was appointed to the Chair of Mental Philosophy and Logic in University College, London, and opened his class in January, 1867. He carefully prepared courses of lectures for his classes on Systematic Psychology, Ethical Theory, and Logic――inductive and deductive. He mainly directed his teaching to the elaboration and explication of psychological doctrines, and the history of philosophy. His knowledge of recorded thought, and of the great philosophical systems, ancient and modern, was wide and accurate, while his clear style of stating psychological doctrines and expository powers were remarkable.

For ten years he was Examiner in Philosophy in the University of London. He also acted as Examiner in the University of Aberdeen for two terms. Occasionally he delivered popular lectures at Manchester, Newcastle, and the Royal Institution, London. For several years he gave the philosophical course of lectures to the College of Preceptors. He took an active interest in the business and management of University College, as a member of the Senate, and subsequently as one of the Senate’s Representatives on the Council.

In 1874 Dr. Bain originated a proposal for establishing a Quarterly Journal of Philosophy, and consulted Robertson on the subject. Dr. Bain desired that Professor Robertson should be editor, and after consideration he accepted the editorship. Time, however, was required to obtain the approbation and promise of support from, at least, some of the eminent living writers on philosophy. Accordingly both made efforts by personal interviews and correspondence, and they received sufficient encouragement to make arrangements for the publication. Under the title of _Mind: a Quarterly Journal of Psychology and Philosophy_, the first number appeared in January, 1876. Robertson was editor of _Mind_ for sixteen years, and expended a great amount of thought and labour upon it. Besides his own original articles, and many reviews of works on psychology, ethics, and philosophy, he carefully revised most of the articles contributed by others before they appeared in the pages of _Mind_. This quarterly publication――the first entirely devoted in the English language to the discussions of mental philosophy, has, during the last twenty years, had a considerable influence upon philosophic thought.

Professor Robertson’s health began to fail twelve years before his death. During the sessions from 1883 to 1888 he had several times to employ substitutes for his teaching work in the College. In the later years of his life he suffered much severe pain, which he bore with great patience. He resigned his Chair in the College on the 7th of May, 1892. His wife died on the 29th of May, the same year; and he himself died on the 20th of September following.1

1 _Philosophical Remains of George Croom Robertson, with a Memoir_, 1894. This volume was edited by Dr. Bain and Mr. T. Whittaker, who had long acted as Robertson’s assistant in preparing notices for _Mind_.

Owing to weak health in the later part of his life, and his death at the comparatively early age of fifty, his writings are not voluminous. Yet they touch on a considerable variety of subjects of much interest, embracing biography, psychology, and philosophy treated historically and associated with the characteristics of an elevated and candid criticism.

He contributed to the _Dictionary of National Biography_ biographies of George Grote, the historian, and his wife, and two of the historian’s brothers――John and Arthur. His contributions to the ninth edition of the _Encyclopædia Britannica_ extended to eight articles, two of which were historical. One of these dealt with Abelard, the famous lecturer and teacher of the twelfth century, a very able and interesting article. Another article was on the remarkable philosopher, Hobbes, a subject to which he had given much attention, and subsequently treated in a book. The remaining articles were philosophical, and treated on Analogy, Analysis, Analytic Judgments, Autonomy, Association, and Axion. All these are admirable specimens of method, clear thought, polished style, and lucid exposition of difficult mental processes.

At an early stage of his life he intended to write a large work on Hobbes, and to treat the subject on comprehensive historic lines. He rightly formed the conception that Hobbes was an important historic character, as he lived and wrote in one of the stirring and revolutionary periods of the history of the Island. He had made some progress in research and had prepared much material for such a work, but untoward circumstances of health prevented him from realising his original conception. He, however, as mentioned before, contributed an article on Hobbes to the _Encyclopædia_; and in 1886 a volume on Hobbes appeared as one of the series, entitled _Philosophical Classics for English Readers_. It is not written on a large scale, yet it is a compact and excellent treatise. He shows a fine historic insight into the social and political conflicts of the period, with reference to their influence upon Hobbes’s views and opinions. Robertson’s remarkable historic faculty is clearly manifested in this volume. His appreciation and criticism of Hobbes’ works, and his influence on subsequent writers, is marked by thoroughness, candour, and accuracy. The treatise is a model of its kind, and is recognised as the best existing monograph on the subject.

To conclude, the preceding account of Scottish Philosophy covers nearly two centuries. The Scottish Philosophers mainly concentrated their efforts on mental philosophy――the explication of the human mind, psychology, moral and political science. Their works present a body of doctrines and reflective thought which are well worth careful study. For the mind alone constitutes the distinctive glory and dignity of man. Insomuch, that it is only by the culture of the mind and the moral sentiments that mankind can hope to attain a more elevated and higher stage of civilisation.