“He, who does not know the entries, the exits will fail him.”
[Baqir Sharīf al-Qurashi, The life of Imam Muhammad al-Jawad, Wonderful Maxims and Arts, 2005]
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Muhammad al-Taqi 25
ninth of the Twelve Imams of Twelver Shi'ism 811–835Related quotes

“He who knows does not speak; he who speaks does not know.”
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“It is precisely what he does not know which may destroy him.”
X magazine (1959-62)
Context: The Art of painting is itself an intensely personal activity. It may be labouring the obvious to say so but it is too little recognised in art journalism now that a picture is a unique and private event in the life of the painter: an object made alone with a man and a blank canvas... A real painting is something which happens to the painter once in a given minute; it is unique in that it will never happen again and in this sense is an impossible object. It is judged by the painter simply as a success or failure without qualification. And it is something which happens in life not in art: a picture which was merely the product of art would not be very interesting and could tell us nothing we were not already aware of. The old saying, “what you don’t know can’t hurt you”, expresses the opposite idea to that which animates the painter before his canvas. It is precisely what he does not know which may destroy him.
“He who does not look before him stays behind.”
Chi non guarda dinanzi rimane di dietro.
Della Prudenza et Dottrina del Re, p. 14.
Translation reported in Harbottle's Dictionary of quotations French and Italian (1904), p. 268.