The most brilliant thoughts may enter a child's head, or rather, the most brilliant sayings may fall from his lips, just as the most valuable diamonds may fall into his hands, without his having any right either to the thoughts or to the diamonds. At his age, he has no real property of any kind. A child's utterances are not the same to him as to us; he does not attach to them the same ideas. If he has any ideas at all on the subject, they have neither order nor coherence in his mind; in all his thoughts nothing is certain or stable. If you watch your supposed prodigy attentively, you will sometimes find him a well-spring of energy, clear-sighted, penetrating the very marrow of things. Much oftener the same mind appears commonplace, dull, and as if enveloped in a dense fog. Sometimes he outruns you, and sometimes he stands still. At one moment you feel like saying, "He is a genius," and at another, "He is a fool." You are mistaken in either case: he is a child; he is an eaglet that one moment beats the air with its wings, and the next moment falls back into the nest.

In spite of appearances, then, treat him as his age demands, and beware lest you exhaust his powers by attempting to use them too freely. If this young brain grows warm, if you see it beginning to seethe, leave it free to ferment, but do not excite it, lest it melt altogether into air. When the first flow of spirits has evaporated, repress and keep within bounds the rest, until, as time goes on, the whole is transformed into life-giving warmth and real power. Otherwise you will lose both time and pains; you will destroy your own handiwork, and after having thoughtlessly intoxicated yourself with all these inflammable vapors, you will have nothing left but the dregs.

Émile — Part 52

Nothing has been more generally or certainly observed than that dull children make commonplace men. In childhood it is very difficult to distinguish real dullness from that misleading apparent dullness which indicates a strong character. At first it seems strange that the two extremes should meet in indications so much alike; and yet such is the case. For at an age when man has no real ideas at all, the difference between one who has genius and one who has not is, that the latter entertains only mistaken ideas, and the former, encountering only such, admits none at all. The two are therefore alike in this, that the dullard is capable of nothing, and the other finds nothing to suit him. The only means of distinguishing them is chance, which may bring to the genius some ideas he can comprehend, while the dull mind is always the same.

Émile — Part 52