Scepticism. Scepticism (σκέπτεσθαι, doubt), is that negative species of philosophy which, founding on the alleged contradiction, whether direct or indirect, of the primary data of consciousness, pronounces philosophy false and truth impossible; or, more briefly, it is that negative system of philosophy which, by doubting of everything beyond the region of phenomena, doubts the possibility of all speculation.

In order to doubt, man must begin somewhere, and the admission by the sceptic of the truthfulness of phenomena is alike necessary and convenient. For an absolute scepticism regarding the energies of the human faculties, even when admitted to be self-consistent, and acquitted of contradiction, is, as self-destructive, absolutely impossible. If I am sceptical of my own faculties when they doubt, this very scepticism annihilates that doubt, and renders me incapable of advancing a step. The highest form which scepticism can assume is that of convicting the data of consciousness of mutual exclusiveness, whether possible or actual. It is the business of the sceptic, accordingly, to destroy, not to establish; to pull down, not to build up. He accepts his premises from the dogmatist, and strives, by bringing them into hostile collision, to convict him of absurdity. It is the business of the dogmatist to develop with consistency the facts which consciousness reveals; it is the business of the sceptic to review the labours of the dogmatist, and discover, if possible, an inconsistency in the primary facts which are subjected to his criticism. The function of the sceptic is quite a legitimate one, accepting as he does both his method and his material from the dogmatist; but pursuing his aim in an entirely different spirit, and with a widely different end. The highest end of the dogmatist is to produce an intellectual harmony; the highest end of the sceptic is to generate an intellectual chaos. The intuition of truth is what the dogmatist seeks; what the sceptic longs for is the absolute doubtfulness of all conviction. Both start from common ground in starting from the acceptation of phenomena; both arrive at directly opposite conclusions in arriving, the one at affirmation, the other at doubt. The dogmatist, the emblem of impatience, is earnest and incessant in his pursuit of truth; the sceptic, the picture of composure, is finely indifferent and delightfully dubious over everything which claims the name of truth. The dogmatist, positive in his assurance of the criterion of what he seeks, has a constant trust in the attainability of philosophy; the sceptic, on the other hand, who harbours the sole conviction that all truth is vain, believes (if a sceptic can be said to believe) in the absolute impossibility of philosophy. Dogmatist and sceptic alike agree in accepting the foundations of knowledge; the dogmatist, reliant on the strength of his intuitions, boldly pushes beyond phenomena, and affirms his conviction of the existence of self, the world, and Deity as entities; the sceptic, again, who freely doubts all intuitions, chooses to think of these essences as so many popular illusions, or at best as so many fond dialectics. The dogmatist accepts of his intuitions, and carelessly multiplies or as carelessly diminishes them; the sceptic, ever on the watch, argues their original falsehood from their positive contradiction in the hands of the dogmatist. The veracity of consciousness, so far as testifying to the truthfulness of phenomena are, at the outset, accepted alike by dogmatist and sceptic; and it depends scepticism entirely on the measure of consistency with which the dogmatist shall work out his problem, whether or not he shall have left room for the keen-eyed and persistent sceptic. If the dogmatist succeeds in elaborating his undertaking throughout with entire consistency, philosophy and nature will be reconciled; but if he does not succeed in this endeavour, consciousness will prove only a bundle of antilogies, and scepticism will reign supreme. Considered under one aspect, the sceptic stands opposed to the dogmatist and not to truth, in so far as he engages to convict of contradiction the principles which philosophy has developed. Considered under another and a higher aspect, he stands opposed both to truth and dogmatism, in so far as he doubts of everything beyond phenomena, in convicting of contradiction the principles on which philosophy itself is founded. The former may be called relative, the latter absolute scepticism. It will thus be seen what are the legitimate relations of sceptic and dogmatist. That man is not a sceptic who exercises doubt as a means, but not as an end. This temporary doubt is but a passing phase of every strong and earnest mind in search of the truth. In the intellectual constitution of some, and particularly of those in whom their intuitions prove too strong for their logic, this salutary disposition becomes temporarily tainted as by a sort of predominating disease. Yet it is the truth which the thinker is in search of, and not universal doubt as an ultimate end. Not a few of the most illustrious thinkers which the world has known seem to have spent much of their time in this atmosphere. Witness the Analogy of Bishop Butler and the Passions of Blaise Pascal, where abundant evidence will be found, particularly in the under-current of those writers' minds, of the truthfulness of this statement. What is usually known as the Cartesian doubt is by no means an uncommon feature in the history of thoughtful men. "Who never doubted, never half believed."

Speculative thought had scarcely dawned upon the minds of the Grecian sages, when scepticism began stealthily to insinuate its doubts. No sooner had dogmatism fairly gained time to develop itself into full blossom, than we find scepticism, its negative correlate, springing up in its shade. As action and reaction constantly recur with the force of their compensating influence, so the speculative efforts of Socrates, of Plato, and of Aristotle, required to be succeeded by the destructive philosophy of Pyrrho of Elis and his school. Plato had developed his ideal theory to find it rudely taken to pieces by Aristotle, who afforded to philosophy as baseless a foundation, in his boasted Logic, as the system of speculation which he had so ruthlessly destroyed. If Plato's theory could be shown to be misleading, a similar proof could be led against that of his opponent. Sense could only furnish the mind with outward phenomena, and formal logic could carry it no farther. It is the privilege of logic to analyse and regulate, not to synthesize and amplify. It belongs not to logic, but to a quite different department of human knowledge, to furnish the material out of which to construct a philosophy of real convictions. As at once the law of thought and of things, logic is properly both subjective and objective. It is constantly engaged on the evolution of identical propositions,

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1 Yet this self-contradictory principle is that which Jouffroy, usually so just a thinker, calls the "one irrefutable argument of scepticism." (See Ménages Philosophiques.) 2 See Diog. Laërt., lib. ix., Pyrrho, passim. 3 See Sextus Empiricus, Pyrrh. Hypotypo., passim; Diogenes Laërtius, lib. ix., Pyrrho; Home's Treatise of Human Nature, vol. i.; Hamilton's edition of Reid, p. 744. 4 See Hamilton's Discussions on Philosophy, p. 87, second edition. Scepticism, and at no point in any process of demonstration is it possible to detect any addition made to the quantum of existence already realized. To metaphysics it belongs to furnish the facts of existence which are competent to human knowledge. Thinking, under this relative phase, neither Plato nor Aristotle had taken any definite account of; and hence Pyrrho and the sceptics seized upon this, the vulnerable portion of their systems. If one were to trust the absurd stories related of the practical life of Pyrrho, one would be necessitated to suppose him to have been little less than crazy. Such, however, we may be assured he was not. He seems to have been strongly impressed with the mystery and consequent incomprehensibility (ἀναλογία) that surrounded the little life of man. He studied in his early years the doctrines of Democritus, and in his maturer life he followed Alexander into India, bent on philosophical conquest, as his master was upon territorial aggrandizement. He studied the doctrines of the Magi, and held converse with the Gymnosophists. Struck by the devout faith of the latter in doctrines so singular and so unusual to the mind of a Greek, he doubtless reflected deeply on the origin of knowledge, and particularly on the formation of belief. On his return to Elis, men found that he had lost all faith in philosophy: he viewed all doctrines with a profound scepticism, and began to live a life of wonderful simplicity and of wonderful indifference. He died at the age of ninety, and bequeathed his name to all succeeding sages who might choose to adopt his system of opinions.

The next thinker of any note who chose Pyrrhonism or Scepticism as his creed was Timon, a physician of Phlius (B.C. 279), a keen and restless wit, and a man of genius, who wrote those satirical poems known as Συναίσθησις. If further proof were wanting of the perfect sanity of Pyrrho, the faithful adherence of this caustic humorist, who was wont to wonder how his master could contrive to live “the only man as happy as a god,” were sufficient of itself to establish it. Timon was much too great a humorist to follow Pyrrho if he had not been really worthy of being followed. After the Pyrrhonian school of Greece, Ἀνεσίδημος, Cyprus and Seleucia afforded two pupils to Timon, in Dioscorides and Euphranor, who served to close the old sceptical school of Greece. Its adherents taught the complete renunciation of all science, and the necessity of maintaining a complete apathy to all impressions.

The Pyrrhonists gathered fresh strength in the new sceptical school, which was inaugurated by one of its most distinguished advocates, Ἀνεσίδημος, who flourished a little later than Cicero. To this philosopher is generally ascribed the systematizing or invention of the ten topics employed by Sextus Empiricus to justify a suspense of all positive opinion. The criticism offered by Ἀνεσίδημος of the principle of Causality is certainly the boldest and most ingenious to be found in the records of the ancient philosophy. The force of his argument lay in the alleged incapability of the human mind to understand the relations of cause and effect.

Of his eight books of Pyrrhonian discourses (Πυρροχωρικῶν ἀποψίων ὀκτὼ βιβλία) only a few fragments now remain. Herodotus of Tarsus, Menodotus, Agrippa (said to be the author of the “five grounds of doubt” current among the later sceptical thinkers), and Antiochus of Laodicea, kept up the sinking credit of the Pyrrhonists till the appearance of Sextus Empiricus (about A.D. 290), a distinguished pupil of Herodotus of Tarsus, and an acute and thoughtful writer. In his Pyrrhonian Outlines, and his books against the Mathematicians (or dogmatists), he has left us an invaluable repository of information respecting the schools of ancient scepticism. This writer was a native of Mitylene, and received his surname, Empiricus, from his connection with that empirical school of physicians who, discarding all science, based their knowledge entirely upon experience. While he availed himself of the labours of his predecessors, and especially of Ἀνεσίδημος, of Agrrippa, and of Menodotus, it is evident from what he has left, that he was capable of higher efforts, both in defining the end and working out the details of a rigorous system of doubt. In his three books, Ἀποψίων ὑποτύπων, he discusses in a fair and his Pyrrhonian manner the radical distinction between Ἀνεσίδημος the sceptics and the dogmatists, and works out with much acuteness and spirit the various contradictions, as they presented themselves to his mind, of the problems of Sense and of Logic, with an occasional detour into the region of Metaphysics. If ever indulges in humour, it is usually of a mild and impersonal character, and never displays anything of that wild satirical banter with which Timon delighted to cover his opponents. The first book of the Pyrrhonian Outlines is occupied with a general exposition of scepticism; in the two remaining books the author takes the dogmatists to task respecting the various problems which occupy their philosophy. He opens his first book by a chapter devoted to Dogmatics and Sceptics, in which he shows that they form the two great classes of philosophical thinkers. Towards the end of that chapter he throws in a sceptical caution in these words: “I wish to advertise my readers as to what I shall advance, that I do not pretend to establish things as they are, and that I cannot at all assure them that things are as I speak of them.” Having thus made his bow to his audience, he proceeds to lay before them a definition of scepticism. “The sceptical faculty is,” according to Sextus, “that by which we oppose phenomena and noumena in all possible ways, and by which we arrive, through a counterpoise of things and arguments, first at a suspension of judgment (ἐποπτήσις), and afterwards at entire freedom from passion (ἀπαθεία).” The aim which the sceptic proposed to himself was accordingly twofold: first, intellectual, to reach absolute suspension of judgment; and second, moral, to attain to a condition of perfect calm. The latter alternative was probably supposed to depend entirely on the accomplishment of the former; so that when the doubter had reached the absolute state of intellectual suspense, he would necessarily experience in his inmost soul that perfect quiet which the thinker so greatly longs for. At all events, little attention was given by the ancient Pyrrhonists to this the moral part of their task. We shall confine attention exclusively to the intellectual phases of scepticism, and give a running outline of these celebrated Hypotheses. They are a summing up of all previous Pyrrhonic ideas, and succeeding sceptics, Hume included, have only, with a slight divergence, traversed the old road.

It will be observed, from the above definition of scepticism, that, as has already been stated, it is not the business of the thorough-going doubter to play the sceptic in the most absolute sense; on the contrary, he accepts of the phenomena of nature as he finds them, and, trusting to his instincts, he rests his practical life upon this empirical basis, and eschews altogether the dogmatical folly of perpetually pursuing that which he can never attain. The dogmatist tries to find a speculative criterion by which to test his philosophizings; while the sceptic, who fancies lie Scepticism has a thorough conviction of the fruitlessness of all such attempts, chooses to repose in his practical security, and leaves the dogmatist unaided to pursue his vain wanderings in search of his darling ignis fatuus. On this point Sextus is very explicit. "When," he says, "we inquire whether an object is such as it appears, we grant the appearance of it; we do not inquire and hesitate concerning what appears, but concerning what is said of this appearance." (Pyrrh. Hypot., Lib. i., c. x.)

The sceptic's conviction of the impossibility of finding a criterion of truth results from a multitude of considerations, all of which may be referred to the following three heads:—1. The subject of knowledge; 2. The object of knowledge; 3. The relation of subject and object, or from knowledge itself. Sextus Empiricus has chosen to follow a much more complicated order, but all his more important considerations will be found included under these three divisions.

1. As to the sceptical contradictions which are found to emerge from a contemplation of the knowing mind or subject of knowledge, the first and most obtrusive are to be found in the region of Sensation, and the last and most recondite in the sphere of Intelligence. Phenomena are apprehended by the former faculties, Substances by the latter. Now, not only are those faculties found to disagree in themselves; they are found also to contradict one another. Not only do the results which the Senses supply contradict each other; these same results clash with those furnished by the Intelligence, which in turn are found to be mutually exclusive. The knowledge furnished by Sensation is as fallacious as it is patent. No one doubts that each separate sense affords at different times very different representations of the same object,—nay, are, and must be, diverse in their information at every different moment of time. Again, the senses themselves contradict one another as to the accuracy of their intelligence. Who can assure us, moreover, that the eye, ear, and touch of each separate individual affords him sensations exactly similar to ours? How do I know, for example, that what appears to me red, may not be felt by my neighbour to be yellow? Doubtless he would use the word red exactly as I do; but the puzzle is, does he mean precisely the same thing by it? For aught we know, the senses may be quite peculiar in each individual, and may give quite different reports to different men. What shall we say, then, of the accuracy of external observation, seeing that it is upon such testimony that the greater portion of it must rest? Human Sensations are modified by organization, by the distance of objects, by the physical and moral changes which take place in man, according as he is asleep or awake, in infancy or old age, in motion or at rest, pre-occupied with love or hatred, with joy or sorrow. And who is there can discover the means of rectifying such inevitable mistakes? Who will furnish man with a sensational criterion? The task is hopelessly in vain. The natural inference for the sceptic is of course ἐπίστασθαι, or, I suspend my judgment.

But again, Sextus strives to find a basis for his doubt in the elements of the intelligence, and particularly in Logic and in logical phenomena. Let it not be supposed that a sceptic will be prepared to pass by any truth which is alleged to bear the special marks of an original conviction. It matters not how augustly these principles, affirmed to be a priori, may be ushered in, or with what profound reverence we would call upon men to fall down and worship when what is called a primary truth is unveiled in their presence; the sceptic replies calmly, as is his wont, that he must have evidence ere he bows down before those awful beliefs, warranting, nay, compelling him in a sort, to affix to them his unhesitating assent. Sextus takes a somewhat easier road to his doubt, and leads a proof of the radical falsehood of those beliefs which we call original, by a simple reference to the various and equivocal representation which they have received at the hands of the dogmatists, real and apparent. And in doing so, unfortunately, his task was easy. He finds little difficulty, for example, in evoking discrepancies connected with the idea of Cause, which philosophers have since grappled with, and grappled in vain. But here he simply chronicled the labours of his predecessor Ænesidemus. "For," he remarks, "if we cannot understand a cause before its effect, seeing that it is relative; and if it is necessary to understand it as being before the effect, seeing that it is the cause of that effect; then it is quite impossible to understand anything to be before that which we cannot understand anything to be, and hence it is impossible to understand that there is a cause."

The only respectable attempt made by philosophers, either ancient or modern, to solve this difficulty of the identity of Cause and Effect is that of Sir William Hamilton, and it may fairly be questioned whether that illustrious thinker has succeeded in unveiling the mystery which generated the ingenious quibble of the subtle old sceptic. Having so far disposed of the data of consciousness, Sextus next directs his doubt against the faculties of Demonstration. And in combating Logic, he boldly affirms that "it may not exist." (Pyrrh. Hypot., Lib. ii., c. 13.) He shows with much acuteness that demonstration never adds anything to the quantum of thought; but he does not succeed in disentangling the form from the matter of thought in the demonstrative process. Seeing that there is nothing but the evolution of identical propositions, so long as we choose to employ the method of demonstration, he at once sets the process aside as quite useless, or at least very doubtful; and in this his example has subsequently been followed by more than one philosopher who professed a very different creed. Sextus concludes thus:—"If these things which we have advanced in favour of demonstration be like the truth (for we do not at all oppose them), and if the arguments which we have advanced against demonstration be like the truth, we ought to arrest our judgment both for and against, and should say it is equally uncertain whether there is or is not any demonstration." (Lib. ii., c. 13.) So far the Subject of knowledge.

2. Scepticism may be inferred from the endless contradictions which emerge upon an examination of the object of knowledge. The object of knowledge is composed of phenomena and noumena. The former we apprehend through our faculties of observation, the latter we apprehend through the higher faculties of intelligence. In the first place, every object is in relation to some other or others; and hence, in order to comprehend the part, we would require previously to comprehend the whole. But this is impossible. Again, in external perception no object is apprehended by itself, and out of relation to a representing medium. However anxious we may be to seize upon the real object, the intervening medium perpetually presents itself. This Sextus, and all subsequent philosophers till Dr Thomas Reid, implicitly inferred from the principle first explicitly enunciated by Empedocles, that "the relation of knowledge inferred an analogy of existence." A word on the second head of this subject; and to take a single example from one of the higher existences which human intelligence is affirmed capable of apprehending. Sextus opens his third book with a chapter on "God," towards the close of which he calmly expresses the following sentiment:—"Hence we also conclude that perhaps those who say there is a God cannot be excused from impiety; for in affirming that he exercises a providential care over all things, they say that he is the author of evil; and if they say that his providence extends only to some

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1 See the Eighth Opinion regarding Causality in Appendix i. to his Discussions on Philosophy, second edition. Scepticism, things and not to all, they will be forced to confess that God is either envious or weak, all of which cannot be said without manifest impiety." The doubt which is thus generated by the heathen strikes at the very idea of a God. Proofs \textit{a priori} and \textit{a posteriori}, piled up like Ossa upon Pelion, would avail little against such an opponent.

3. Advancing to the third head, it becomes manifest from what has been affirmed of its constituents, the subject and the object of knowledge, that when they enter into relation, and form knowledge, this result must partake more or less of the character of its factors. Scepticism has already emerged from an examination of the subject and the object of knowledge, and it can hardly be supposed to be eliminated by bringing them into correlation. The incompleteness and inconsistency of knowledge render it for ever a favourite butt for those who are sceptically inclined.

To his general arguments against the leading principles of the dogmatists, Sextus added some special arguments against various of their theories, which we need not here examine. We shall add a word as to the manner in which he acquitted himself of his task.

That Sextus Empiricus was a sceptic in reality, as he was certainly in name, no one will be prepared to deny. That he proved his right to the title also, by proving his right to doubt, we are likewise prepared to admit. The dogmatists, one and all, quailed under the open blows which he dealt at their laboured edifice, and many of those blows unhappily took effect. Amid constant marks of acuteness, he occasionally betrays an ingenuity worse than frivolous, and now and then misses the real question by his fondness for logomachy. But from this criticism Sextus Empiricus could possibly shield himself by taking refuge in his historical calling. And from this position we are not anxious to drive him, as the remark very likely applies as much to his school as to himself. Were we to trust for the veracity of consciousness to the development which it received from the philosophers previous to Sextus, all thinking men would infallibly be sceptical. For a positive proof of falsehood in one particular datum of consciousness is sufficient to establish, on the principle \textit{falsus in uno, falsus in omnibus}, a presumption of probable falsehood in them all. More than one supposed datum of internal experience had been convicted of falsehood, and the Dogmatists, and not Human Nature, stood chargeable with the offence.

With Sextus Empiricus the lists of Scepticism close for many centuries. The next to whom they shall be opened is to David Hume, the last and unquestionably the greatest of either ancient or modern sceptics. No name of any great lustre intervenes to fill up the long blank of sixteen centuries from Sextus to Hume. Practically, no doubt, many men like Montaigne (1538–1592) adhered to the sceptical creed. But they were in general either too wise to publish their opinions to the world, or too wary to let it know how they thought. When they gained boldness to let the world look on their views they for the most part strove to diminish any savour of odium which might be supposed to attach to a Pyrrhonist, by professing, at the conclusion of their speculations, the very greatest reverence for the Holy Scriptures. That this reverence was sometimes real, however inconsequent, cannot be denied. It was doubtless so in the case of La Mothe le Vayer, a French author of great learning and judgment (1586–1672), who openly professed Scepticism in favour of Religion. The same may be said of his disciples Sorbière (1615–1670) and Foucher (1644–1696); of Himilaym (died in 1679); of Huet (1630–1721); and of Joseph Gianvill, an Englishman (1636–1680), who may be regarded as the predecessor of Hume. One cannot speak so confidently of Charron (1541–1603), who was a disciple of Montaigne; of Sanches or Sanctius, a Spaniard by birth, who professed medicine and philosophy at Toulouse till the time of his death in 1632; and of the celebrated P. Bayle (1647–1706). That these writers were at bottom genuine sceptics can hardly admit of a doubt. We should certainly have had to chronicle many names which now are forgotten, or which never were heard of, had not the Inquisition spread terror over the free thought and free expression of Europe during the middle ages. But the device, of fancying that men were never safe so long as they trusted a whit to their Reason—that they must discard this faculty as repugnant in the highest sense to that superior faculty of divine Faith which is conferred immediately by the Spirit of God, has been exceedingly common in the various Christian schools of theology. It is thus that Scepticism, during many centuries, has been called in to support the Roman Catholic religion, and its advocates have supposed that by sapping the entire intellectual convictions of their fellows, they should thereby advance in the highest degree the eternal interests of their souls.

The scepticism of Hume (1711–76) was beyond all question the most thorough and wide-reaching that philosophy had yet witnessed. He reduced philosophers to such straits that they were compelled either to refute his arguments (a thing not to be thought of upon his own principles), or ruefully to confess the vanity of their pursuits and the consequent folly of their lives. His \textit{Treatise of Human Nature} was published in 1738, when Hume was in his twenty-seventh year. A book written by so young a man, with such marvellous acuteness and solidity of thought, displaying such a mastery over the difficulties of style, and such singular control over his own passions, was quite as unparalleled in the history of philosophy as the doctrines which it put forth were novel and alarming. Of the host of assailants which the book ultimately called forth, unquestionably the most respectable was Dr Thomas Reid. But so profoundly had the great sceptic meditated his task, and with such wondrous skill had he entrenched himself over the \textit{débris} of all previous systems of philosophy, that Reid, who was not his match either in subtlety or in comprehension of thought, assailed Hume at first in a somewhat clumsy manner, and really missed the point of the very method which the Pyrrhonist had chosen. This method was no other than that of Pyrrho and the old sceptical school of Greece. Sextus Empiricus starts by the admission of phenomena, and proceeds to hew down all else which the dogmatists had raised; David Hume starts with the popular theory of experience, then so much vaunted by philosophers, and proceeds with surprising coolness to mow down every intellectual up-growth for which his theory was not capable of accounting. In open argument, in candid statement, and in solid attack, the Scottish sceptic is greatly in advance of the earlier Pyrrhonists of Greece. He is in a great measure free from that ingenious jugglery and conscious or unconscious sophistry with which the older sceptics are so justly chargeable. He seldom allows his logic to degenerate into logomachy, and very rarely substitutes a paralogism for a sound argument. To assure the reader of his genuine position, Hume takes pains to inform him as follows:—“Should it here be asked me,” he says, “whether I sincerely assent to this argument, which I seem to take such pains to inculcate, and whether I be really one of those sceptics who hold that all is uncertain, and that our judgment is not in any thing possessed of any measure of truth and falsehood, I should reply, that this question is entirely superfluous, and that neither I nor any other person was ever sincerely and constantly of that opinion. Nature, by an absolute and uncontrollable necessity, has determined us to judge as well as to breathe and feel; nor can we any more forbear viewing certain objects in a stronger and fuller light, upon account of their customary connection with a present im- Scepticism than we can hinder ourselves from thinking as long as we are awake, or seeing the surrounding bodies when we turn our eyes towards them in broad sunshine. Whoever has taken the pains to refute the evils of this total scepticism, has really disputed without an antagonist, and endeavoured by arguments to establish a faculty which nature has antecedently implanted in the mind and rendered unavoidable." (Part iv., § 1.) Locke and the sensationalists had furnished Hume with the theory of experience, on which they had endeavoured to found all knowledge. "Tis therefore," he informs us, "by experience only that we can infer the existence of one object from that of another." (Part iii., § 6.) Knowledge, according to him, had its origin in "impressions and ideas," meaning by the former "all our sensations, passions, and emotions as they make their first appearance in the soul," and by the latter "the faint images of these in thinking and reasoning." Knowledge was accordingly reduced in the last analysis to Sensation from which to derive all its elements, simple and complex. "Now, since nothing is ever present," writes Hume, "to the mind but perceptions, and since all ideas are derived from something antecedently present to the mind, it follows that 'tis impossible for us so much as to conceive or form an idea of anything specifically different from ideas and impressions." (Part ii., § 6.) This being posited, the work afterwards is comparatively easy. Our ideas of space and time he strips of their infinity, and as products of sense, are reduced, the one to visible and tangible extension, the other to an observed succession or simultaneousness of objects. Personal identity he shows to be a mere imagination of the philosophers. "It must," he reasons, "be some one impression that gives rise to every real idea. But self or person is not any one impression. It cannot therefore be from any of these that the idea of self is derived, and consequently there is no such idea." (Part iv., § 6.) His theory of Causation, on the refutation of which so much needless philosophical acumen has been expended, when examined closely, reduces itself to these very narrow limits. "We have no other notion of cause and effect," he tells us, "but that of certain objects which have been always conjoined together, and which in all past instances have been found inseparable." The theory was not new to philosophy, whatever it might be to Hume. It had been signalized before, to confine ourselves to British philosophers, both by Glanvill and by Hobbes; but whether or not Hume had the merit of discovering the doctrine, we must at least attribute to him the credit of having first awakened the zeal of philosophers towards the theory. It will be observed that, so far from ascribing anything to that alleged character of power which resides in every cause, he attributes the existence of such an idea to "a popular habit or custom." He could find no warrant for such an idea in the compass of his experience, and why should he adhere to it if it was not conformable to the basis of all his reasoning? "The mind," he tells us plainly, "feels no sentiment or inward impression from this succession of objects; consequently there is not in any single instance of cause and effect anything which can suggest the idea of power or necessary connection." (Essays, § 7.) Nothing can be more explicit than this. All substances, of whatever class, are on this theory simply fancies—mere creatures of the imagination. Phenomena may now reign undisturbed in the safe enjoyment of a shadowy rule; the substances or noumena which had been contrived to sustain them being convicted of non-existence, must troop off like spectres at the approach of dawn. Advancing with the same stately tread among the moral judgments of men, the sceptic grinds down with relentless heel every vestige of a moral world beyond the mere sphere of sensations. The only rational motive for man is his personal interest; the only determining motive is a necessary constraint upon his so-called free-will. But Scepticism, the sceptic is not content with treading down the intellectual and moral nature of man; he advances a step further, and prostrates his natural theology, by trying to prove that the belief in the existence of Deity is uncertain, as effected by the illegitimate exercise of the human faculties. (See Dialogues, 1779.) With this last word the sceptic has completed the writing of destruction to which he held dogmatism doomed. The edifice of human knowledge, from its most general proposition down to its minutest detail, here received its final blow. The last pillar on which it stood has now been wrenched from under it, and the whole philosophic world cannot hold it up. The sceptic, so far from regretting the results of his industry, regards the spectacle with some measure of satisfaction; but without relaxing into any very hilarious merriment, he turns, bows an adieu to Reason, and, hand in hand with Nature, goes on his way. "I dine," Hume tells us, "I play a game of backgammon, I converse and am merry with my friends; and when, after three or four hours' amusement I would return to these speculations, they appear so cold, and strained, and ridiculous, that I cannot find in my heart to enter into them any further." (Part iv., § 7.) And so Scepticism again triumphs, and Dogmatism goes to the wall.

A word in conclusion in behalf of Truth and Dogmatism. Conclusion. And in the first place, one must deplore the variation and error which stand recorded against philosophy in all ages, by the rashness or prejudice of its votaries, by which it has become a by-word in the mouth of the unthinking, and a subject of scorn to the sceptical. This can hardly be wondered at. Were the inquirer not driven towards speculation as by a blind original instinct, which finds itself gratified by the merest husks which nature knows, he should long ere now have consigned philosophy, with all her solemn splendours, to the uttermost regions of the reign of night. But so long as man is born into the world to inquire, men will continue to speculate, and thankful to nature for the bestowal of such a boon, be content, if the results of their investigations were merely to feel the refreshing gale which blows towards them from the distant fields of reality, to lie down with a wistful sigh, and dream of the world which is beyond, whose balmy breezes they have experienced, but on whose shores they are not destined to set foot. It is matter of congratulation, to all who love Truth, that this august object of desire stands serene above the high strifes of men, and remains a pure and everlasting possession to all who humbly and faithfully seek it. In the war which the sceptic wages he aims his weapons not so much against Truth as against her pretentious high priest, who, in his haste for his own honour more than for the glory of her to whom he has sworn fealty, has made haste to deliver the oracle before the goddess had granted the response. Thus it has ever been, that in a sceptical combat the attention of the wise is directed to the dogmatist and to the sceptic, as to the sole combatants. There has hitherto been no sceptic who has attempted to show, much less who has succeeded in demonstrating, that the primary facts of consciousness, either in themselves or in their necessary consequences, are mutually exclusive—are reciprocally repugnant. Philosophy accordingly remains as of old, untainted by the fierce struggles which have been waged within her borders; ready as of old to welcome to her shrine all of clean hands and of pure heart; satisfied that, while her forbearance has been frequently converted into an encouragement of vanity, she possesses, nevertheless, the high prerogative of bestowing upon all her true worshippers the clear eye and the courageous heart. The crude Sensationalism which usurped the place of philosophy could hardly have been too rudely dethroned; and assuredly it met with as speedy a downfall as ever system knew. Sceptre. Since Hume, the Scottish school can boast of Reid, Stewart, and Hamilton; the French of Royer Collard, Joffroy, and Cousin; the Germans of Kant, Fichte, Hegel, and Schelling. The Scottish philosophers, who have generally been accused of timidity, have striven hard to erect a bulwark around our original beliefs which should defy all sceptical assault. The French, much more brilliant than either of their neighbours, have borrowed from them nearly all that is of much value in their Eclecticism. The German speculative have sought truth in a much more profound and also in a much more profitless manner than Schaffhausen—either the French or the Scottish schools. They have pursued philosophy much beyond the verge of the romantic, and have exposed it to every possible evil. That which in the hands of Kant was meant to repel the Scepticism of Hume and the Sensationalism of Locke, in its turn produced a Scepticism as real as that which it had replaced, and grew under the hands of Hegel and Schelling into a wild agglomeration of Pantheism, in which no man can believe, because, it is said, no man can understand.

(J.D.—S.)