satisfy the virtue of wisdom. "In a broad way, a truth may be defined as any cognitive material that is affectively satisfying to a social group, so that it may be employed as an instrument to action." This is not subjectivism, for the categories are social creations, and are the most permanent elements in human thought. The categories are real, not only in the sense that they are "postulates so valued by human beings that the latter would maintain their belief in them at whatever empirical cost," but also because the external universe "is such that when human organisms come into experiential relations with it, their percepts and categories are fairly efficient in enabling them to effect an adjustment with it."
The rapid advance of science has caused a decline of religious beliefs and accentuated the disagreement between the moral structure or personality of individuals, and the social and economic environment. The moral personality is a combination of moral ideas and morality proper, which latter is chiefly instinctive, and innate. So far as moral ideas are concerned, moral personality is adaptive to the social milieu, and evolves in accordance with economic and other demands. On the other hand, the instinctive basis of morality proper is more rigid and inelastic, for the moral instincts have not greatly varied during the historical period. However, there is evidence to show that the moral instincts are also modifiable and subject to social evolution—viz.: the fidelity of the dog to his master, an instinct newly acquired since the origin of the species; female modesty, an instinct greatly modified since the advent of Christianity; modifications in the instincts of the children of alcoholics, and of those who have excelled in some form of human activity. Such and other evidence cited indicates that moral instincts are probably to some extent subject to artificial selection, and that eugenic measures for this purpose are worthy of consideration.
For two thousand years logic was regarded as the unquestionable basis of philosophy and all science. To-day, nothing is so unanimously questioned by the different schools as the success of any attempt to found a logical system. The logic of Plato, Aristotle, Descartes, Leibniz, and Spinoza all claimed to contain a criterion of truth not dependent on experience. They made the mistaken attempt to infer being from mere thought. There have been three notable efforts made to establish a reformed logic, resulting in the psychological, the transcendental or Kantian, and the symbolic logic. A fourth might be mentioned, in connection with such names as Mach, Schiller, and Poincaré. Psychological logic is found in the works of Herbart, Brentano,
