tag="{http://www.w3.org/1999/xhtml}a">^[B] Both are transformations of 'the given' by the will, but, like the postulate of causal series, experience may confirm them. Kant's a priori activity of the mind may thus in a sense supply an answer to Hume—but only in a voluntaristic philosophy which would probably have seemed too bold both to him and to Hume.

There can be no doubt that we do not approach the data of perception in an attitude of quiescent resignation. Our desires and needs equip us with assumptions and 'first principles,' which originate from within, not from without. But how precisely should this mental contribution to knowledge be conceived? In the last chapter of his Psychology James suggested that the mind's organization is essentially biological. It has evolved according to sound Darwinian principles, and in so doing the fittest of its 'variations' have survived. But were these variations quite fortuitous? May they not have been purposive responses to the stimulation of environment? Can logic have been invented like saws and ships for purposes of human service? These are some of the stimulating questions which James's work in Psychology has suggested.

FOOTNOTES:

CHAPTER III

The new psychology of James was bound to produce a new theory of knowledge, and though it did not actually explore this problem, it contained several valuable suggestions upon the subject. For instance, in a brief passage discussing 'The Relations of Belief and Will,' James pointed out that belief is essentially an attitude of the will towards an idea, adding that in order to acquire a belief 'we need only in cold blood act as if the thing in question were real, and keep acting as if it were real, and it will infallibly end by growing into such a connection with our life that it will become real' (ii., p. 321). This passage is an outline of the doctrine of 'The Will to Believe,' which he was afterwards to develop so forcibly.

Again, in his last chapter, James criticized the doctrine of Spencer that all the principles of thought, all its general truths and axioms, were derived from impressions of the external world. He argued, on the other hand, that such ways of looking at phenomena must originate in the mind, and be prior to the experience which confirms them. Without digging further into the character of this mental contribution to knowledge, James contented himself with the suggestion that the use of these axiomatic principles might be construed in Darwinian style as a 'variation' surviving by its fitness, thus introducing into his account of mental process the important idea that thinking might be tested by its vital value.

What if knowledge be neither a dull submission to dictation from without nor an unexplained necessity of thought? What if it be a bold adventure, an experimental sally of a Will to live, to know and to control reality? What if its principles were frankly risky, and their truth had to be desired before it was tested and assured? In a word, what if first principles were to begin with postulates? Thus the way is paved from the new psychology to a new theory of knowledge. A third alternative to the banal dilemma of 'empiricism' or 'apriorism' suggests itself.

The old empiricist view, as typified by Mill, was that the mind had been impressed with all its principles, such as the truths of arithmetic, the axioms of geometry, and the law of causation, by an uncontradicted course of experience, until it generalized facts into 'laws,' and was enabled to predict a similar future with certainty. But this theory had really been exploded in advance by Hume. Facts do not appear as causally connected, nor, if they did, would this guarantee that they will continue to do so in the future. The continuum of experience, we may add, is not given as a series of arithmetical units or geometrical equalities, unless we deliberately measure it out in accordance with mathematical principles. Empiricism thus gives no real account of the scientific rational order of the world.

But does it follow from the failure of empiricism that apriorism is true? This has always been assumed, and held to dispense rationalist philosophers from giving any direct and positive proof that these principles are a priori truths. But manifestly their procedure is logically far from cogent. If a third explanation can be thought of, it will not follow that apriorism is true. All that follows is that something has to be assumed before experience proves it. What that something is, and whence it comes, remains an open question. Moreover, apriorism has not escaped from the empirical doubt about the future. Even granted that facts now conform to the necessities of our thoughts, why should they so comport themselves for ever?

Let us, therefore, try a compromise, which ignores neither that which we bring to experience (like empiricism), nor that which we gain from experience (like apriorism). This compromise is effected by the doctrine of postulation. For though a postulate proceeds from us, and is meant to guide thought in anticipating facts, it yet allows the facts to test and mould it; so that its working modifies, expands, or restricts its demands, and fits it to meet the exigencies of experience, and permits, also, a certain reinterpretation of the previous 'facts' in order to conform them to the postulate.

A postulate thus fully meets the demands of apriorism. It is 'universal' in claim, because it is convenient and economical to make a rule carry as far as it will go; and it is 'necessary,' because all fresh facts are on principle subjected to it, in the hope that they will support and illustrate it. Yet a postulate can never be accused of being a mere sophistication, or a bar to the progress of knowledge, because it is always willing to submit to verification in the course of fresh experience, and can always be reconstructed or abandoned, should it cease to edify. A long and successful course of service raises a postulate to the dignity of an 'axiom'—i.e., a principle which it is incredible anyone should think worth disputing—whereas repeated failure in application degrades it to the position of a prejudice—i.e., an a priori opinion which is always belied by its consequences.

A 'postulate' thus differs essentially from the 'a priori truth' by its dependence upon the will, by its being the product of a free choice. We have always to select the assumptions upon which we mean to act in our commerce with reality. We select the rules upon which we go, and we select the 'facts' by which we claim to support our rules, stripping them of all the 'irrelevant' details involved by their position in the flux of happenings. Thus we emphasize that side of things which fits in with our expectations, until the facts are 'faked' sufficiently to figure as 'cases' of our 'law.' Postulation and the verifying of postulates is thus a process of reciprocal discrimination and selection. The postulate once formulated, we seek in the flux for confirmations of it, and thus construct a system of 'facts' which are relative to it; that is how the postulate reacts upon experience. If, on the other hand, this process of selection is unfruitful, and the confirmations of our rule turn out infinitesimal, we alter the rule; and thus the 'facts' in the case reject the