Children learn at their own pace, and it is a mistake to try to force them. The great incentive to effort, all through life, is experience of success after initial difficulties. The difficulties must not be so great as to cause discouragement, or so small as not to stimulate effort. From birth to death, this is a fundamental principle.
Source: On Education, especially in early childhood, 1926, Pt. 2： Education of character, chap. 3: the first years.
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