There are, it is true, many people who say that they "do not believe" in either heredity or environment. Such people see the difficulties of the disputants and reject both alternatives. They prefer to say frankly that they do not understand the situation; that life is too complex to be solved by puny human intellects. Or they resort to some equally unintelligible explanation, such as "Fate" or "Nature"--which is but another way of saying that we never _can_ understand. On the other side stands the scientist who refuses to shut his eyes to _any_ established facts, and insists upon trying to understand as much as possible, though he may never hope to understand all. But no one is prepared to say authoritatively that either heredity or environment is the exclusive or even the predominant factor in determining the character of the individual. Indeed, the voice of the scientist, which is the only authoritative voice we have in such matters, is telling us very plainly that the whole question of "heredity _or_ environment" is not a real question at all: we are confronted in every child with a case of heredity _and_ environment, and the practical question is how to control the latter so as to get the most from the former. To begin, then, in a modest way to understand what is understandable, in the faith that understanding will grow with thought and observation, is the first duty of those who are not content to fold their hands in resignation or despair. We know that we can control wherever we have real knowledge. The cook knows that she cannot make roast duck out of pork chops; but she knows also that she can make palatable and digestible pork chops by proceeding in one way, and that she can make tough and sickening pork chops out of the same materials by changing her procedure. In the same way the scientific approach to the problem of child training teaches us that, while we cannot make a "swan out of a goose," we can make the gosling into a better goose or a poorer goose by the treatment we apply to it.