The psychological forces which tend toward individualism have been already stated to be the self-assertive instincts and impulses. They are all variations of the effort of the living being first to preserve itself and then to rise to more complicated life by entering into more complex relations and mastering its environment. Spinoza's "_sui esse conservare_," Schopenhauer's "will to live," Nietzsche's "will to power," the Hebrew's passionate ideal of "life", and Tennyson's "More life, and fuller" express in varying degree the meaning of this elemental bent and process. Growing intelligence adds to its strength by giving greater capacity to control. Starting with organic needs, this developing life process may find satisfactions in the physical world in the increasing power and mastery over nature gained by the explorer or the hunter, the discoverer, the craftsman, or the artist. It is when it enters the world of persons that it displays a peculiar intensity that marks the passions of individualism _par excellence_. We note four of these tendencies toward self-assertion. =1. Sex.=--The sex instinct and emotion occupies a peculiar position in this respect. On the one hand it is a powerful socializing agency. It brings the sexes together and is thus fundamental to the family. But on the other hand it is constantly rebelling against the limits and conventions established by the social group for its regulation. The statutes against illicit relations, from the codes of Hammurabi and Moses to the latest efforts for stricter divorce, attest the collision between the individual's inclination and the will of the group. Repeatedly some passion of sex has broken over all social, legal, and religious sanctions. It has thus been a favorite theme of tragedy from the Greeks to Ibsen. It finds another fitting medium in the romance. It has called into existence and maintains in every large city an outcast colony of wretched creatures, and the evils which attend are not limited in their results to those who knowingly take the risks. It has worked repeated changes in the structure of the family authorized by society. Its value and proper regulation were points at issue in that wide-reaching change of mores attendant upon the Reformation, and apparently equilibrium has not yet been reached.