The struggle for existence among men is not now, therefore, as it was in primitive days, a life-and-death competition for food and shelter. Individuals have come to recognize each other’s rights and to seek even their own advantage by co-operation rather than by strife. The association of individuals in the family and the community serves to preserve the weak whom a keen struggle for existence would eliminate. Our whole system of poor-relief, hospitals, and care for the defective is based upon the idea of giving a fair chance to those who otherwise would be crowded out of the struggle for existence altogether. The competition today is not so much between individuals as among groups, small or large, including competition between whole nations of men. [Sidenote: The relative influence of inheritance and environment.] =The Factors in Social Progress.=—Two factors have greatly influenced the course of social evolution or social progress. These factors are _inheritance_ and _environment_. By inheritance we mean the qualities, physical and mental, which each generation inherits from the generation preceding. By environment we mean the general surroundings, physical and social, in which the people live. Mankind influences these surroundings to a considerable extent and moulds them to his own needs, but in turn is also influenced by them. Everything that is characteristic of man is the result of these two forces, inheritance and environment. In some things the first is more important, in others the second. For example, under normal conditions the height of a man or woman is determined almost altogether by inheritance, for no one by taking thought can add a cubit to his stature. Intelligence, likewise, is to a large degree an inherited quality. But morals, manners, education, and personal habits are determined much more largely by environment than by inheritance. [Sidenote: Which is the more potent influence?] The respective influences of inheritance and environment cannot, however, be in all cases clearly separated. Both often work to produce the same result, as when a person who inherits a strong body and a sound mind is fortunate enough to be placed in an environment where both body and mind are developed by out-of-door life and a good education. Sometimes they work in opposite directions, as when a child starts life with a strong physique and good natural intelligence, but grows up in a crowded tenement amid sordid conditions which weaken the one and fail to afford scope for the other. We cannot say, therefore, that one factor is always stronger or weaker than the other. The social progress of the race is promoted by improving both influences. Environment especially can be improved by human effort. Man’s control of his inheritance is not nearly so complete, but everything that conduces to the betterment of health or education and promotes a higher morality is a step towards improving its influence. [Sidenote: The two forms of inheritance.]