I do not mean to suggest that self-control can be dispensed with entirely ; on the contrary, no man can live a consistent life without it. What I do mean is, that self-control ought only to be needed in unforeseen situations, for which education has not provided in advance. It would have been foolish, even if it had been possible, to train the whole population to have, without effort, the sort of courage that was needed in the war. This was an exceptional and temporary need, of so extraordinary a kind that all other education would have had to be stunted if the habits required in the trenches had been instilled in youth.
Source: On Education, especially in early childhood, 1926, Pt. 2：Education of character, chap. 4: Fear.
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