The degree to which self-control is necessary in life depends upon the early treatment of instinct. ...
The function of education is to guide instinct into the directions in which it will develop useful rather than harmful activities. If this task has been adequately performed in early years, a man or woman will, as a rule, be able to live a useful life without the need of severe self-control except, perhaps, at a few rare crises. If, on the other hand, early education has consisted in a mere thwarting of instinct, the acts to which instinct prompts in later life will be partly harmful, and will therefore have to be continually restrained by self-control.
Source: Marriage and Morals, 1929.
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