I have hardly ever known a mathematician who was capable of reasoning.

from Benjamin Jowett's interpretive vernacular translation (1871) of Plato's Republic, Book VII, 531-e. Plato actually has Socrates say that few mathematicians are dialecticians (διαλεκτικοί) (Jowett, Plato's Republic: The Greek Text, Vol. I "Text", 1894), by which he refers to step by step reasoning based on mutual agreement, (G. M. A. Grube, Plato's Republic (1974), Book VII, note 13). It is an accurate observation on the primitive mathematics of his day.