Nassim Nicholas Taleb. Black Swan (№ 389245)

Sextus Empiricist told a parable about a painter named Apelles who wanted to depict the foam falling from the lips of a horse. No matter how he struggled, nothing came of it. In furious desperation, the artist grabbed the sponge which wiped the brush, and threw it at the picture. Looking at the trail left by the sponge, he saw a very accurate picture of the foam, which could not be achieved.