HUME Hume is the most illustrious and typical of modern sceptics. His scepticism is sometimes placed, as by 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 arrives. The Treatise (1739-40) is a reductio ad absurdum of the principles of Lockianism, inasmuch as these principles, when consistently applied, leave the struc ture of experience entirely "loosened" (to use Hume's own ex pression), or cemented together only by the irrational force of custom. Hume's scepticism thus really arises from his thorough going empiricism. Starting with "particular perceptions" or iso lated 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 dis appears. Hume's analysis of the conceptions of a permanent world and a permanent self reduces us to the sensationalistic rel ativism of the Greek Sophist, 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 Enquiry (1748) 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 ir rational 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 repetition or custom. This point of view is applied in the Treatise uni versally. All real connection or relation, therefore, and with it all possibility of an objective system, disappears ; it is, in fact, excluded by Hume from the outset, for "the mind never perceives any real connection among distinct existences."