In protecting a younger child, one can speak to the senior with a sharpness and suddenness which would not otherwise be justified, but which have their uses through the strong impression produced by their unexpectedness. All these are useful lessons, which it is hardly possible to give naturally in any other way. It is a folly and a waste of time to give abstract moral instruction to a child ; everything must be concrete, and actually demanded by the existing situation.
Source: On Education, especially in early childhood, 1926, by Bertrand Russell<
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