SCEPTICISM (<rcrTOM<u, I consider, reflect, hesitate, doubt), a term signifying etymologically a state of doubt or indecision in the face of mutually conflicting statements. It is implied, moreover, that this doubt is not merely a stage in the road to true knowledge, but rather the last result of investigation, the conclusion that truth or real knowledge is unattainable by man. Therefore, in general terms, scepticism may be summarily defined as a thorough-going impeachment of man's power to know a denial of the possibility of objective knowledge.
Trust, not distrust, is the primitive attitude of the mind, i. What is put before us, whether by the senses or by the statements of others, is instinctively accepted as a veracious report, till experience has proved the possibility of deception. In the history of philosophy affirmation precedes negation; dogmatism goes before scepticism. And this must be so, because the dogmatic systems are, as it were, the food of scepticism. Accordingly, we find that sceptical thought did not make its appearance till a succession of mutually inconsistent theories as to the nature of the real had suggested the possibility that they might all alike be false. _. The Sophistic epoch of Greek philosophy was, in great Sophist*. P art > suc h a negative reaction against the self-confident assertion of the nature-philosophies of the preceding age. Though scepticism as a definite school may be said to date only from the time of Pyrrho (q.v.) of Elis, the main currents of Sophistic thought were sceptical in the wider sense of that term. The Sophists (q.v.) were the first in Greece to dissolve knowledge into individual and momentary opinion (Protagoras), or dialectically to deny tne possibility of knowledge (Gorgias). In these two examples we see how the weapons forged by the Historical appear- dogmatic philosophers to assist in the establishment of their own theses are sceptically turned against philosophy in general. As every attempt to rationalize nature implies a certain process of criticism and interpretation to which the data of sense are subjected, and in which they are, as it were, transcended, the antithesis of reason and sense is formulated early in the history of speculation. The opposition, being taken as absolute, implies the impeachment of the veracity of the senses in the interest of the rational truth proclaimed by the philosophers in question. Among the pre-Socratic nature-philosophers of Greece, Heraclitus and the Eleatics are the chief representatives of this polemic. The diametrical opposition of the grounds on which the veracity of the senses is impugned by the two philosophies (see HERACLITUS, PARMENIDES, ELEATIC SCHOOL) was in itself suggestive of sceptical reflection. Moreover, the arguments by which Heraclitus supported this theory of the universal flux are employed by Protagoras to undermine the possibility of objective truth, by dissolving all knowledge into the momentary sensation or persuasion of the individual. The idea of an objective flux, or law of change constituting the reality of things, is abandoned, and subjective points of sense alone remain which is tantamount to eliminating the real from human knowledge.
Still more unequivocal was the sceptical nihilism expressed by Gorgias (q.v.): (i) nothing exists; (2) if anything existed, it would be unknowable; (3) if anything existed and were knowable, the knowledge of it could not be communicated. His arguments were drawn from the dialectic which the Eleatics had directed against the existence of the phenomenal world. But they are no longer used as indirect proofs of a universe of pure and unitary Being. The prominence given by most of the Sophists to rhetoric, their cultivation of a subjective readiness as the essential equipment for life, their substitution of persuasion for conviction, all mark the sceptical undertone of their teaching. This attitude of indifference to real knowledge passed in the younger and less reputable generation into a corroding moral scepticism which recognized no good but pleasure and no right but might.
The scientific impulse communicated by Socrates was sufficient to drive scepticism into the background during the great age of Greek philosophy (i.e. the hundred years preceding socrmte* Aristotle's death, 323 B.C.). The captious logic of the Megarian school (q.v.) was indeed in some cases closely related to sceptical results. The school has been considered with some truth to form a connecting link with the later scepticism, just as the contemporary Cynicism and Cyrenaicism may be held to be imperfect preludes to Stoicism and Epicureanism. The extreme nominalism of some of the Cynics also, who denied the possibility of any but identical judgments, must be similarly regarded as a solvent of knowledge. But with these insignificant exceptions it holds true that, after the sceptical wave marked by the Sophists, scepticism does not reappear till after the exhaustion of the Socratic impulse in Aristotle.
Scepticism, as a distinct school, begins with Pyrrho of Elis, who maintained that knowledge of things is impossible and that we must assume an attitude of reserve (etroxh)- The /v/rAo Pyrrhonists were consistent enough to extend their doubt even to their own principle of doubt. They thus attempted to make their scepticism universal, and to escape the reproach of basing it upon a fresh dogmatism. Mental imperturbability (4Tapaa) was the result to be attained by cultivating such a frame of mind. The happiness or satisfaction of the individual was the end which dominated this scepticism as well as the contemporary systems of Stoicism and Epicureanism, and all three philosophies place it in tranquillity or self-centred indifference. It is men's opinions or unwarranted judgments about things, say the sceptics, which betray them into desire, and painful effort and disappointment. From all this a man is delivered who abstains from judging one state to be preferable to another. But, as complete inactivity would have been synonymous with death, it appears to have been admitted that the sceptic, while retaining his consciousness of the complete uncertainty enveloping every step, might follow custom in the ordinary affairs of life.
The scepticism of the New Academy (more strictly of the Middle Academy, under Arcesilaus and Carneades) differed very little from that of the Pyrrhonists. The differences Ancient asserted by later writers are not borne out on investigation. But the attitude maintained by the Academics was chiefly that of a negative criticism of the views of others, in parAcfdeay ticular of the somewhat crude and imperious dogmatism of the Stoics. They also, in the absence of certainty, allowed a large scope to probability as a motive to action, and defended their doctrine on this point with greater care and skill. The whole position was stated with more urbanity and culture, and was supported, by Carneades in particular, by argumentation at once more copious and more acute. It seems also true that the Academics were less overborne than the Pyrrhonists by the practical issue of their doubts (imperturbability); their interest was more purely intellectual, and they had something of the old delight in mental exercitation for its own sake (see ARCESILAUS, CARNEADES, AENESIDEMUS, AGRIPPA and SEXTUS EMPIRICUS).
Both Zeller and Hegel remark upon the difference between the calm of ancient scepticism and the perturbed state of mind evinced by many modern sceptics. Universal doubt was the instrument which the sceptics of antiquity modem recommended for the attainment of complete peace scepti- o f mind. By the moderns, on the other hand, doubt is portrayed, for the most part, as a state of unrest and painful yearning. Even Hume, in various passages of his Treatise, speaks of himself as recovering cheerfulness and mental tone only by forgetfulness of his own arguments. His state of universal doubt he describes as a " malady " or as " philosophical melancholy and delirium." The difference might easily be interpreted either as a sign of sentimental weakness on the part of the moderns or as a proof of the limitation of the ancient sceptics which rendered them more easily satisfied in the absence of truth. It seems to prove, at all events, that the ancient sceptics were more thoroughly convinced than their modem successors of the reasonableness of their own attitude.
It may be doubted whether the thoroughgoing philosophical scepticism of antiquity has any exact parallel in modern times, with the single exception possibly of Hume's Treatise on Human Nature. It is true we find many thinkers who deny the competency of reason when it ventures hi any way beyond the Sphere of experience, and such men are not unfrequently called sceptics. This is the sense in which Kant often uses the term, and the usage is adopted by others for example, in the following definition from Ueberweg's History of Philosophy: " The principle of scepticism is universal doubt, or at least doubt with regard to the validity of all judgments respecting that which lies beyond the range of experience." The last characteristic, however, is not enough to constitute scepticism, in the ancient sense. Scepticism, to be complete, must hold that even within experience we do not rationally conclude but are irrationally induced to believe. " In all the incidents of life," as Hume puts it, " we ought still to preserve our scepticism. If we believe that fire warms, or water refreshes, 'tis only because it costs us too much pains to think otherwise" (Treatise, bk. i. iv. 7). This tone, which fairly represents the attitude of ancient sceptics, is rare among the moderns, at least among those v:ho are professed philosophers. It is more easily matched hi the unsystematic utterances of a man of the world like Montaigne.
2. One form of scepticism, however, may be claimed as an exclusively modern growth, namely, philosophical scepticism Scepti- in the interests of theological faith. These sceptics ctem to the are primarily Apologists. Their scepticism is simply interest of a me ans to the attainment of a further end. They find that the dogmas of their church have often been attacked in the name of reason, and it may be that some of the objections urged have proved hard to rebut. Accordingly, in an access of pious rage, as it were, they turn upon reason to rend her. They endeavour to show that she is in contradiction with herself, even on matters non-theological. Thus the " imbecility " of reason becomes their warrant for the reception by another organ i.e. faith of that to which reason had raised objections. The Greeks had no temptation to divide man in two in this fashion. Their scepticism was an end in itself. But this line of argument was latent in Christian thought Pascal.
from the time when St Paul spoke of the " foolishness " of preaching. So Tertullian: " Crucifixus est Dei filius; non pudet, quia pudendum est. Et mortuus est Dei filius; prorsus credibile est, quia ineptum est. Et sepultus resurrexit; certum est, quia impossibile est." But, as Christianity became firmly established, Christian writers 'became more tolerant of speculation, and laboured to reduce the doctrines of the church to a rational system. This was the long task essayed by Scholasticism ; and, though the great Schoolmen of the 13th century refrained from attempting to rationalize such doctrines as the Trinity and the Incarnation, they were far from considering Theory of them as essentially opposed to reason. It was not till the twotowards the close of the middle ages that a sense told "atun of conflict between reason and revelation became oftruta - widely prevalent and took shape in the essentially sceptical theory of the twofold nature of truth. Philosophical truth, as deduced from the teaching of Aristotle, it was said, directly contradicts the teaching of the church, which determines truth in theology; but the contradiction leaves the authority of the latter unimpaired in its own Sphere. It is difficult to believe that this doctrine was ever put forward sincerely; in the most of those who professed it, it was certainly no more than a veil by which they sought to cover their heterodoxy and evade its consequences. Rightly divining as much, the church condemned the doctrine as early as 1276. Nevertheless, it was openly professed during the period of the break up of Scholastic Aristotelianism (see POMPONAZZI).
The typical and by far the greatest example of the Christian sceptic is Pascal (1623-1662). The form of the Pensees forbids the attempt to evolve from their detached utterances a completely coherent system. For, though he declares at times " Le pyrrhonisme est le vrai," " Se moquer de la philosophic c'est vraiment philosopher," or, again, " Humiliezvous, raison impuissante, taisez-vous, nature imbecile," other passages might be quoted in which he assumes the validity of reason within its own Sphere. But what he everywhere emphatically denies is the possibility of reaching by the unassisted reason a satisfactory theory of things. Man is a hopeless enigma to himself, till he sees himself in the light of revelation as a fallen creature. The fall alone explains at once the nobleness and the meanness of humanity; Jesus Christ is the only solution in which the baffled reason can rest. These are the two points on which Pascal's thought turns. Far from being able to sit in judgment upon the mysteries of the faith, reason is unable to solve its own contradictions without aid from a higher source. In a somewhat similar fashion, Lamennais (in the first stage of his speculations, represented by the Essai sur I' indifference en matiere religieuse, 1817-1821) endeavoured to destroy all rational certitude in order to establish the principle of authority; and the same profound distrust of the power of the natural reason to arrive at truth is exemplified (though the allegation has been denied by the author) in Cardinal Newman. In a different direction and on a larger scale, Hamilton's philosophy of the conditioned may be quoted as an example of the same religious scepticism (see HAMILTON, SIR WILLIAM). The theological application and development of Hamilton's arguments in Mansel's Bampton Lectures On the Limits of Religious Thought marked a still more determined attack, in the interests of theology, upon the competency of reason.
Passing from this particular vein of sceptical or semi-sceptical thought, we find, as we should expect, that the downfall of Scholasticism, and the conflict of philosophical theories and re- ~^ ..^ ligious confessions which ensued, gave a decided impetus . /L. to sceptical reflection. One of the earliest instances of ga(J inh this spirit is afforded by the book of Agrippa of Nettesheim _/ H ..: es (1487-1535), De incertitudine et vanitate scientiarum.
This turn of thought is not confined, however, to Christian thinkers; it appears also in the Arabian philosophy of the East. Ghazali (g.f.) in his Tahafot al-Filasifa (" The Collapse of the Philosophers ") is the advocate of complete philosophical scepticism in the interests of orthodox Mahommedanism an orthodoxy which passed, however, in his own case into a species of mysticism. He did his work of destruction so thoroughly that Arabian philosophy died out after his time in the land of its birth.
Sceptical reflection rather than systematic scepticism is what meets us in Michel de Montaigne (1533-1592), though the elaborate presentation of sceptical and relativistic arguments in his " Apologie de Raimond-Sebond " (Essais, ii. 12), and the emblem he recommends a balance with the legend, " Que scay-je ? " might allowably be adduced as evidence of a more thoroughgoing Pyrrhonism. In his " tesmoynages de nostre imbecillite " he follows in the main t!ie lines of the ancients, and he sums up with a lucid statement of the two great arguments in which the sceptical thought of every age resumes itself the impossibility of verifying our faculties, and the relativity of all impressions. In the concluding lines of this essay, Montaigne seems to turn to " nostre foy chrestienne " as man's only succour from his native state of helplessness and uncertainty. But undoubtedly his own habitual frame of mind is better represented in his celebrated saying " How soft and healthful a pillow are ignorance and incuriousness. . . for a well-ordered head." More inclined than Montaigne to give a religious turn to his reflections was his friend Pierre Charron (1541-1603), who in his book DC la sagesse systematized in somewhat scholastic fashion the train of thought which we find in the Essais. Frangois Sanchez (1562-1632), professor of medicine and philosophy in Toulouse, combated the Aristotelianism of the schools with much bitterness, and was the author of a book with the title Quod nihil scitur. Of more or less isolated thinkers may be mentioned Francois de la Mothe le Vayer (1588- 1672), whose Cinq Dialogues appeared after his death under the pseudonym of Orosius Tubero; Samuel Sorbiere (1615-1670), who translated the Hypotyposes Pyrrhoneae of Sextus Empiricus; Simon Foucher (1644-1696), canon of Dijon, who wrote a History of the Academic*, and combated Descartes and Malebranche from a sceptical standpoint. The work of Hieronymus Hirnhaim of Prague (1637-1679), De typho generis humani sire scientiarum humanarum inani ac ventoso tumore, was written in the interests of revelation. This is still more the case with the bitter polemic of Daniel Huet (1630-1721), Censura philosophiae Cartesianae, and his later work, Traite philosophique de la faiblesse de I'esprit humain. The scepticism of Joseph Glanvill (q.v.), which is set forth in his two works The Vanity of Dogmatizing (1661) and Scepsis scientifica (1665), has more interest for Englishmen. More celebrated than any of the above was Pierre Bayle (1647-1706), whose scepticism lay more in his keen negative criticism of all systems and doctrines which came before him as literary historian than in any theoretic views of his own as to the possibility of knowledge. Bayle also paraded the opposition between reason and revelation; but the argument in his hands is a double-edged weapon, and when he extols the merits of submissive faith his sincerity is at least questionable.
3. Hume is the most illustrious and indeed the typical sceptic of modern times. His scepticism is sometimes placed, as we have seen *' * s b v Kant, in his distrust of our ability and right to pass beyond the empirical Sphere. But it is essential to the sceptical position that reason be dethroned within experience as well as beyond it, and this is undoubtedly the result at which Hume finally arrives. The Treatise is a rtductio ad absurdum of the principles of Lockianism, inasmuch as these principles, when consistently applied, leave the structure of experience entirely " loosened " (to use Hume's own expression) , or cemented together only by the irrational force of custom. Hume's scepticism thus really arises from his thoroughgoing empiricism. Starting with " particular perceptions " or isolated ideas let in by the senses, he never advances beyond these " distinct existences." Each of them exists on its own account ; it is what it is, but it contains no reference to anything beyond itself. The very notion of objectivity and truth therefore disappears. Hume's analysis of the conceptions of a permanent world and a permanent self reduces us to the sensationalistic relativism of Protagoras. He expressly puts this forward in various passages as the conclusion to which reason conducts us. The fact that the conclusion is in " direct and total opposition " to the apparent testimony of the senses is a fresh justification of philosophical scepticism. For, indeed, scepticism with regard to the senses is considered in the Inquiry to be sufficiently justified by the fact that they lead us to suppose " an external universe which depends not on our perception," whereas " this universal and primary opinion of all men is soon destroyed by the slightest philosophy." Scepticism with regard to reason, on the other hand, depends on an insight into the irrational character of the relation which we chiefly employ, viz. that of cause and effect. It is not a real relation in objects, but rather a mental habit of belief engendered by frequent repetititon or custom. This point of view is applied in the Treatise universally. All real connexion or relation, therefore, and with it all possibility of an objective system, disappears; it is, in fact, excluded by Hume Hume db initio, for " the mind never perceives any real connexion among distinct existences." Belief, however, just because it rests, as has been said, on custom and the influence of the imagination, survives such demonstrations. " Nature," as Hume delights to reiterate, " is always too strong for principle." " Nature, by an absolute and uncontrollable necessity, has determined us to judge as well as to breathe and feel." The true philosopher, therefore, is not the Pyrrhonist, trying to maintain an impossible equilibrium or suspense of judgment, but the Academic, yielding gracefully to the impressions or maxims which he finds, as matter of fact, to have most sway over himself. 1 The system of Kant, or rather, that part'of his system expounded in the Critique of Pure Reason, though expressly distinguished by its author from scepticism, has been included by sceptical many writers in their survey of sceptical theories, side or The difference between Kant, with his system of pure Kantiaareason, and any of the thinkers we have passed in review '*"* is obvious; and his limitation of reason to the Sphere of experience suggests in itself the title of agnostic or positivist rather than that of sceptic. Yet, if we go a little deeper, there is substantial justification for the view which treats agnosticism of the Kantian type as essentially sceptical in its foundations and in its results. For criticism not only limits our knowledge to a certain Sphere, but denies that our knowledge within that sphere is real; we never know things as they actually are, but only as they appear to us. But this doctrine of relativity really involves a condemnation of our knowledge (and of all knowledge), because it fails to realize an impossible and self-contradictory ideal. The man who impeaches the knowing faculties because of the fact of relation which they involve is pursuing the phantom of an apprehension which, as Lotze expresses it, does not apprehend things, but is itself things; he is desiring not to know but to be the things themselves. If this dream or prejudice be exploded, then the scepticism originating in it and a large proportion of recent sceptical thought does so originate loses its raison d'ltre* The prejudice, however, which meets us in Kant is, in a somewhat different form, the same prejudice which is found in the tropes of antiquity what Lotze calls the " inadmissible relation of the world of ideas to a foreign world of objects." For, as he rightly points out, whether we suppose idealism or realism to be true, in neither case do the things themselves pass into our knowledge. No standpoint is possible from which we could compare the world of knowledge with such an independent world of things, in order to judge of the conformity of the one to the other. But the abstract doubt " whether after all things may not be quite other in themselves than that which by the laws of our thought they necessarily appear " is a scepticism which, though admittedly irrefutable, is as certainly groundless. No arguments can be brought against it, simply because the scepticism rests on nothing more than the empty possibility of doubting. This holds true, even if we admit the " independent " existence of such a world of things. But the independence of things may with much greater reason be regarded as itself a fiction or prejudice. The real " objective " to which our thoughts must show conformity is not a world of things in themselves, but the system of things as it exists lor a perfect intelligence. Scepticism is deprived of its persistent argument if it is seen that, while our ndividual experiences are to be judged by their coherence with the context of experience in general, experience as a whole does not admit of being judged by reference to anything beyond itself.
To the attack upon the possibility of demonstration, inasmuch as every proof requires itself a fresh proof, it may quite "airly be retorted that the contradiction really lies in the demand 1 Much the same conclusion is reached in what is perhaps the ablest English exposition of pure philosophic scepticism since Hume A. J. Balfour's Defence of Philosophic Doubt (1879).
1 It may be as well to add that the sceptical side of Kantianism is nainly confined to the Critique of Pure Reason, but this side of <antian thought has been most widely influential. The remarks made above would not apply to the coherent system of idealism which may be evolved from Kant's writings, and which many would coniider alone to deserve the name of Kantianism or Criticism.
Prejudices oa whkh scepticism rest*.
for proof of the self-evident, on whicn all proof must ultimately depend. It is of course always possible that in any particular case we may be deceived; we may be assuming as self-evidently true what is in reality not so. But such incidental lapses are found to correct themselves by the consequences in which they involve us, and they have no power to shake our trust in the general validity of reason. It may, however, be granted that the possibility of lapse throws us open to the objections, ingenuous or disingenuous, of the sceptic; and we must remain exposed to them so long as we deal with our first principles as so many isolated axioms or intuitions. But the process of selfcorrection referred to points to another proof the only ultimately satisfactory proof of which first principles admit. Their evidence lies in their mutual interdependence and in the coherence of the system which they jointly constitute.
Of a scepticism which professes to doubt the validity of every reasoning process and every operation of all our faculties it is, of course, as impossible as it would be absurd to offer Function an y refutation. This absolute scepticism, indeed, can hardly be regarded as more than empty words; the position which they would indicate is not one which has ever existed. In any case, such scepticism is at all times sufficiently refuted by the imperishable and justifiable trust of reason in itself. The real function of scepticism in the history of philosophy is relative to the dogmatism which it criticizes. And, as a matter of fact, it has been seen that many so-called sceptics were rather critics of the effete systems which they found cumbering the ground than actual doubters of the possibility of knowledge in general. And even when a thinker puts forward his doubt as absolute it does not follow that his successors are bound to regard it in the same light. The progress of thought may show it to be, in truth, relative, as when the nerve of Hume's scepticism is shown to be his thoroughgoing empiricism, or when the scepticism of the Critique of Pure Reason is traced to the unwarrantable assumption of things-in-themselves. When the assumptions on which it rests are proved to be baseless, the particular scepticism is also overcome. In like manner, the apparent antinomies on which such a scepticism builds will be found to resolve themselves for a system based on a deeper insight into the nature of things. The serious thinker will always repeat the words of Kant that, in itself, scepticism is " not a permanent resting-place for human reason." Its justification is relative, and its function transitional.
AUTHORITIES. Ancient scepticism is fully treated in the relative parts of Zeller's Philosophic der Griechen. See also works quoted in the biographical articles; Brochard, Les Sceptiques grecs (1887); Ed. Caird, Evolution of Theology in the Greek Philosophers (1904); Norman MacColl, Greek Sceptics from Pyrrhp to Sextus (1869); Haas, De philosophorum scepticorum successionibus (1875). Among other works may be mentioned Staudlin, Geschichte und Geist a. Scepticismus, vorziiglich in Riicksicht auf Moral u. Religion (1794); Tafel, Geschichte d. Scepticismus (1834); E. Saisset, Le Scepticisme: /Enesideme, Pascal, Kant (1875). For a modern view see A. J. Balfour, Defence of Philosophic Doubt (1879). All histories of philosophy deal with scepticism, and general accounts will be found in T. M. Robertson's Short History of Free Thought and A. W Benn's History of Modern Rationalism. See also AGNOSTICISM, RATIONALISM.
(A. S. P.-P.;X.)
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)