ABSTRACT
1. The criterion of validity is to be arrived at, according to our view, from an analysis of the idea of validity itself and its implications. What these are we have already seen in a general way, and it only remains to show how this conception of validity indicates of itself the nature of the criterion. Validity, then, as we have seen, is assigned to a judgment on the ground of some other judgment. The isolated judgment qua isolated may possess a certain force, a felt certainty, but cannot be said to be valid or invalid. Its validity is tested by comparison with some other judgment with which it is in some way connected. But in this it is not implied that the second judgment is of itself necessarily and intrinsically valid. Indeed, such a requirement would itself contradict the notion of validity as just analysed. According to that analysis we cannot anywhere find an isolated judgment of final and intrinsic validity, for the very reason that intrinsic validity as applied to a single judgment is a contradiction. But where, then, can a test—I do not yet say the ultimate test, but any test—be found? From judgment A I appeal to B, and from B to C, and so on; but if G is not valid, why should B be so, and if B is not valid, why A? In short, if validity cannot be found in any one judgment, where is it? We answer, where the conception of validity would have it be, namely, in the consilient judgments themselves, as forming a consilient system. A is judged valid in view of B, B in view of C, C in view of A. Then the three judgments A, B, and C mutually support one another, and this mutual support constitutes their validity. Two mutually supporting or consilient judgments constitute the minimum requirements of validity. If A is such as of itself to lead to B, while B also leads to A, the two judgments A and B are, so far as we confine our view to them, valid. Validity, in short, is to be measured by consilience.
