they yield? In all these cases the movements are discharged fatally by the vis a tergo which the stimulus exerts upon a nervous system framed to respond in just that way. The IMPULSIVE QUALITY of mental states is an attribute behind which we cannot go." [Footnote: W. James, Psychology, vol. II, p. 550.] It is not true, then, that love of pleasure and fear of pain are the universal motives. It is not true that we inevitably act along the line of least hedonic resistance, that pain necessarily veers us off and pleasure irresistibly attracts. By force of will, by "suggestion" or training, we can go directly counter to the pull of pleasure. It is true that we should not have the instincts and habits and impulses that we do were they not in general useful for our existence or happiness. But the evolutionary process has been clumsy; we are not properly adjusted; we become the victims of ideas fixes; ideas and activities obsess us quite without relation to their hedonic value. So pleasure and pain are not usually the impelling force or conscious motive behind conduct. What they are is-the touchstone, the criterion, the justification. We do not act in ways that bring the greatest happiness, but we ought to. We do not consciously seek happiness, and we ought not to. We ought to continue to care for THINGS and for IDEALS; but the things and ideals we care and work for ought to be such that through them man's welfare is advanced. Are pleasures and pains incommensurable? An objection commonly raised is that pleasures and pains of various sorts are incommensurable; that therefore no calculation of relative advantage is possible; and that the eudaemonistie criterion for action is thereby made impracticable and useless. (1) To this we may reply that the estimation of the relative worth of different kinds of experience is, indeed, often very difficult. But on any theory the decision as to the right is equally complicated and puzzling. The fact that the criterion is difficult to use is no evidence that it is not the right criterion. Which set of consequences will be of most intrinsic worth, it is sometimes impossible to know. But one set is, nevertheless, of more intrinsic worth, and the act that secures them is the best act, even though we do not recognize it as such. There will continue to be, many differences of judgment as to which of alternative possible experiences is the more desirable. But that uncertainty does not alter the fundamental fact that some experiences ARE intrinsically more desirable than others and more deserving of pursuit.