And I hold that in neither case is he to blame: for he did not make his nature, nor did he make the influences which have operated on that nature.
Man is a creature of Heredity and Environment. He is by Heredity what his ancestors have made him (or what God has made him). Up to the moment of his birth he has had nothing to do with the formation of his character. As Professor Tyndall says, "that was done for him, and not by him." From the moment of his birth he is what his inherited nature, and the influences into which he has been sent without his consent, have made him.
An omniscient being—like God—who knew exactly what a man's nature would be at birth, and exactly the nature of the influences to which he would be exposed after his birth, could predict every act and word of that man's life.
Given a particular nature; given particular influences, the result will be as mathematically inevitable as the speed and orbit of a planet.
Man is what heredity (or God) and environment make him. Heredity gives him his nature. That comes from his ancestors. Environment modifies his nature: environment consists of the operation of forces external to his nature. No man can select his ancestors; no man can select his environment. His ancestors make his nature; other men, and circumstances, modify his nature.
Ask any horse-breeder why he breeds from the best horses, and not from the worst. He will tell you, because good horses are not bred from bad ones.
Ask any father why he would prefer that his son should mix with good companions rather than with bad companions. He will tell you that evil communications corrupt good manners, and pitch defiles.
Heredity decides how a man shall be bred; environment regulates what he shall learn.
One man is a critic, another is a poet. Each is what heredity and environment have made him. Neither is responsible for his heredity nor for his environment.
If the critic repents his evil deeds, it is because something has happened to awake his remorse. Someone has told him of the error of his ways. That adviser is part of his environment.