Most people do not take heed of the things they encounter, nor do they grasp them even when they have learned about them, although they think they do.
 Heraclitus, On Nature (c. 535 – c. 475 BCE). copy citation

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Author Heraclitus
Source On Nature
Topic learning encounters
Date c. 535 – c. 475 BCE
Language English
Reference
Note Translated by William Harris
Weblink http://community.middlebury.edu/~harris/Philosophy/heraclitus.pdf

Context

“A foolish man is a-flutter at every word. (87) 55. Fools, although they hear, are like the deaf: To them the adage applies that when present they are absent. (34) 56. Bigotry is the sacred disease. (46) 57. Most people do not take heed of the things they encounter, nor do they grasp them even when they have learned about them, although they think they do. (17) 58. If all existing things were smoke, it is by smell that we would distinguish them. (7) 59. In Hades souls perceive by smelling. (98) 60. Corpses are more fit to be thrown out than dung. (96)” source