I was about fourteen when I first read Oliver Twist, but it filled me with emotions of horror which I could scarcely have borne at an earlier age. Dreadful things should not be known to young people until they are old enough to face them with a certain poise. This moment will come sooner with some children than with others : those who are imaginative or timid must be sheltered longer than those who are stolid or endowed with natural courage. A mental habit of fearlessness due to expectation of kindness should be firmly established before the child is made to face the existence of unkindness.
Source: On Education, especially in early childhood, 1926, Pt. 2：Education of character, chap. 11: Affection and Sympathy
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