Neither reason nor habit can secure us from the fear of a present danger whose degree and kind are unknown, nor from the fear of surprises which we have often experienced.
 Jean-Jacques Rousseau, Emile, or On Education (1762). copy citation

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Author Jean-Jacques Rousseau
Source Emile, or On Education
Topic danger fear
Date 1762
Language English
Reference
Note Translated by Barbara Foxley
Weblink http://www.gutenberg.org/cache/epub/5427/pg5427-images.html

Context

“I have known people who tried to train the children not to fear the dark by startling them. This is a very bad plan; its effects are just the opposite of those desired, and it only makes children more timid. Neither reason nor habit can secure us from the fear of a present danger whose degree and kind are unknown, nor from the fear of surprises which we have often experienced. Yet how will you make sure that you can preserve your pupil from such accidents? I consider this the best advice to give him beforehand. I should say to Emile, "This is a matter of self-defence, for the aggressor does not let you know whether he means to hurt or frighten you, and as the advantage is on his side you cannot even take refuge in flight.” source