for a certain degree of intelligence is required to be able to know that a man knows not, and we must push against a door to know whether it be bolted against us or no
 Michel de Montaigne, The Essays of Michel de Montaigne (1580). copy citation

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Author Michel de Montaigne
Source The Essays of Michel de Montaigne
Topic intelligence
Date 1580
Language English
Reference
Note Translated by Charles Cotton
Weblink http://www.gutenberg.org/files/3600/3600-h/3600-h.htm

Context

“Plato says also, that prudence is no other thing than the execution of this ordinance; and Socrates minutely verifies it in Xenophon. The difficulties and obscurity are not discerned in any science but by those who are got into it; for a certain degree of intelligence is required to be able to know that a man knows not, and we must push against a door to know whether it be bolted against us or no: whence this Platonic subtlety springs, that “neither they who know are to enquire, forasmuch as they know; nor they who do not know, forasmuch as to inquire they must know what they inquire of.” So in this,” source