The real education in justice can only come where there are other children. This is one of many reasons why no child should long be solitary. Parents who have the misfortune to have an only child should do all that they can to secure companionship for it, even at the cost of a good deal of separation from home, if no other way is possible.
Source: On Education, especially in early childhood, 1926, Pt. 2：Education of character, chap. 7: Selfishness and property.
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