If true history contradicts any moral we wish to teach, our moral must be wrong, and we had better abandon it. I quite admit that many people, including some of the most virtuous, find facts inconvenient, but that is due to a certain feebleness in their virtue. A truly robust morality can only be strengthened by the fullest knowledge of what really happens in the world.
Source: On Education, especially in early childhood, 1926, Pt. 2： Education of character, chap. 11: Affection and Sympathy
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