Current forms of scepticism bear intimate relation to dis coveries in the natural sciences and psychology, to the perspective induced by the historical outlook, and to social displacements ac companied by the development of anti-intellectualism. A sum mary (and therefore partial) statement follows :— Physiologism.—Things are external to us in space. Hence, the physiological conditions antecedent to perception interpose a veil between us and objects and direct knowledge is ruled out. Again, the cerebrospinal states on which perception depends may as well be effects of disturbances within the organism as of stimuli from without. Evidently, this view assumes the existence of objects out of relation to consciousness and also that one part of knowledge is valid, disclosing, as it does, reasons for the dubiety of perception.
Psychologism.—Granted that the mind is merely a "natural object," it is conditioned by time no less than by space. But reference to past time presupposes memory, and to future time anticipation. Psychologically, both are untrustworthy; therefore man is confined to the specious present. In any case, whatever may be said for knowledge derived from the past, the future baffles penetration; even "laws of nature" may alter or lapse, and it would seem to follow that all experiential conjunctions are casual. Scepticism of this kind involves the dogma that hypoth eses as to uniformity are inadmissible, and that objective "fact," other minds included, is at best a perilous inference. It may be added that Behaviourism is dogmatic rather than sceptical, being a subtle recrudescence of materialism.
Historicism.—This is sometimes treated as if it were identical with naturalism ; that is, given an evolving series, discovery of origins suffices for "explanation," not merely of "species," but also of "values" in the spiritual and social life. The underlying assumptions are too plain to require comment. Thus, in its scep tical drift, Historicism rather implies that, on review of the past all opinions and, equally, their practical consequences, in institu tions, etc., can be shown to have been bemused by hopeless diversity of judgment. In particular, thinkers who profess to de cide fundamentals, exhibit irremediable contradiction. It is ab surd, then, to claim that ultimates are capable of settlement. This view involves a negative dogma, by denying the possibility of progressive insight—hypothesis can never rise to theory. The process of phenomena, each member its own witness, hides aught that may lie behind.
Pragmatism.—In so far as it embodies an emphatic protest against certain types of philosophy, pragmatism cannot be identi fied with scepticism off-hand. But, being a species of geneticism, it favours sceptical tendencies. "Logical forms and structures are distinctions within the process of reflective and experimental en quiry." If so, all "laws" must be judged evanescent. On this score, pragmatic geneticism and futurism are anti-intellectual.
Notwithstanding, they embrace belief in the creative function of an evolutionary process (Bergson), and justify the voluntaristic creed of modernism (Blondel). Even so, the reason for the validity of the hypothesis is made secondary to other considera tions. Consequences are good, because subserving happiness, etc., and not true, because in agreement with a ratio essendi. Hence the sceptical thrust. Truth is relative to individual activity which happens to be in continuous process of transmutation. Thus, truth can never be more than the best relevant or temporary ad justment ; hence, all questions about the truth must be reckoned artificial. Coming in at the death, intellect can but offer bad reasons for manifest effects. Meantime, it were prudent, perhaps, to regard pragmatism rather as a search for a technique by a generation eager to formulate new values than as bare scepticism. Taken thus, it employs dogmas of its own—reality on the make in linear progress, for example. Nevertheless it is the symptomatic philosophy of a period of disintegration, often doubtful whether the "world-spirit" be for it or against it, and seeking a criterion in "social utility." 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 any refuta tion. 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 criti cizes. 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 succes sors are bound to regard it in the same light. The progress of thought may show it to be 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 un warrantable assumption of things-in-themselves. When the as sumptions on which it rests are proved to be baseless, the par ticular 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.