“ When we educate a man among his fellow-men and for social life, we cannot, and indeed we ought not to, bring him up in this wholesome ignorance, and half knowledge is worse than none. ”
 Jean-Jacques Rousseau, Emile, or On Education (1762). copy citation

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“For my own part, the more I consider this serious crisis and its causes, immediate and remote, the more convinced I am that a solitary brought up in some desert, apart from books, teaching, and women, would die a virgin, however long he lived. But we are not concerned with a savage of this sort. When we educate a man among his fellow-men and for social life, we cannot, and indeed we ought not to, bring him up in this wholesome ignorance, and half knowledge is worse than none. The memory of things we have observed, the ideas we have acquired, follow us into retirement and people it, against our will, with images more seductive than the things themselves, and these make solitude as fatal to those who bring such ideas with them as it is wholesome for those who have never left it.” source