“ Chance gives rise to thoughts, and chance removes them; no art can keep or acquire them. ”
 Blaise Pascal, Pensées (1670). copy citation

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“from the fire, that warmth which affects us in a manner wholly different from touch, the reception of sound and light, all this appears to us mysterious, and yet it is material like the blow of a stone. It is true that the smallness of the spirits which enter into the pores touches other nerves, but there are always some nerves touched. 369 Memory is necessary for all the operations of reason. 370 [Chance gives rise to thoughts, and chance removes them; no art can keep or acquire them. A thought has escaped me. I wanted to write it down. I write instead, that it has escaped me.] 371 [When I was small, I hugged my book; and because it sometimes happened to me to ... in believing I hugged it, I doubted....]” source