Children enjoy fancy when it is pure, that is to say, when it makes no pretence to be reality, but they distinguish sharply between fancy and fact. The person who offers them pretty fairy tales as if they were fact rouses their indignation as soon as they find out the trick that has been played on them.... They have a dislike of humbug, which usually disappears in later life. The habit of screening them from the knowledge of disagreeable truths is not adopted for their sakes although adults may think it is; it is adopted because adults themselves find candour painful.
Source: On Protecting Children from Reality, by Bertrand Russell
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