We must not run the risk that the young people whom we have educated in ignorance will turn to wickedness with delight as soon as they discover that there is such a thing. Unless we can give them an aversion from cruelty they will not abstain from it; and they cannot have an aversion from it if they do not know that it exists.
Source: On Education, especially in early childhood, 1926, Pt. 2： Education of character, chap. 11: Affection and Sympathy
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