need not, therefore, necessarily serve these generic human interests.[3] Therefore, other inducements than the unmitigated impact of pecuniary exigencies may be necessary to bring about a coincidence of class or individual endeavor with the interests of the community. It becomes incumbent on the advocate of _laissez-faire_ to "prove his minor premise." It is no longer self-evident that: "Interests left to themselves tend to harmonious combinations, and to the progressive preponderance of the general good."[4] The natural-rights preconception begins to fall away as soon as the hedonistic mechanics have been seriously tampered with. Fact and right cease to coincide, because the individual in whom the rights are conceived to inhere has come to be something more than the field of intersection of natural forces that work out in human conduct. The mechanics of natural liberty--that assumed constitution of things by force of which the free hedonistic play of the laws of nature across the open field of individual choice is sure to reach the right outcome--is the hedonistic psychology; and the passing of the doctrine of natural rights and natural liberty, whether as a premise or as a dogma, therefore coincides with the passing of that mechanics of conduct on the validity of which the theoretical acceptance of the dogma depends. It is, therefore, something more than a coincidence that the half-century which has seen the disintegration of the hedonistic faith and of the associational psychology has also seen the dissipation, in scientific speculations, of the concomitant faith in natural rights and in that benign order of nature of which the natural-rights dogma is a corollary. It is, of course, not hereby intended to say that the later psychological views and premises imply a less close dependence of conduct on environment than do the earlier ones. Indeed, the reverse may well be held to be true. The pervading characteristic of later thinking is the constant recourse to a detailed analysis of phenomena in causal terms. The modern catchword, in the present connection, is "response to stimulus"; but the manner in which this response is conceived has changed. The fact, and ultimately the amplitude, at least in great part, of the reaction to stimulus, is conditioned by the forces in impact; but the constitution of the organism, as well as its attitude at the moment of impact, in great part decides what will serve as a stimulus, as well as what the manner and direction of the response will be.