Wisdom consists in speaking and acting the truth, giving heed to the nature of things.
 Heraclitus, On Nature (c. 535 – c. 475 BCE). copy citation

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

Context

“Of those whose discourses I have heard there is not one who attains to the realization that wisdom stands apart from all else. (108) 8.. I have searched myself. (101) 9. It pertains to all men to know themselves and to be temperate. (116) 10. To be temperate is the greatest virtue. Wisdom consists in speaking and acting the truth, giving heed to the nature of things. (112) 11.. The things of which there can be sight, hearing, and learning ---- these are what I especially prize. (55) 12. Eyes are more accurate witnesses than ears. (101a) 13. Eyes and ears are bad witnesses to men having barbarian souls.” source