Fire is to represent truth because it destroys all sophistry and lies
 Leonardo da Vinci, The Notebooks of Leonardo Da Vinci (1478 – 1519). copy citation

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Author Leonardo da Vinci
Source The Notebooks of Leonardo Da Vinci
Topic truth fire
Date 1478 – 1519
Language English
Reference
Note Translated by Jean Paul Richter in 1888
Weblink http://www.gutenberg.org/cache/epub/5000/pg5000-images.html

Context

“and maintains truth alone, that is gold. Truth at last cannot be hidden. Dissimulation is of no avail. Dissimulation is to no purpose before so great a judge. Falsehood puts on a mask. Nothing is hidden under the sun. Fire is to represent truth because it destroys all sophistry and lies; and the mask is for lying and falsehood which conceal truth. 685. Movement will cease before we are weary of being useful. Movement will fail sooner than usefulness. Death sooner than I am never weary of weariness.” source