The Republic - pg. 132

"Come, then," I said, "let's see if we can find the way
out. Now we agree that one Nature must practice one
thing and a different nature must practice a different
thing, and that women and men are different. But at
present we are asserting that different natures must
practise the same things. Is this the accusation against us?"
"Exactly"
"Oh, Glaucon," I said, "the power of the contradicting art is grand."
"Why so?"
"Because," I said, "in my opinion, many fall into it even
unwillingly and suppose they are not quarreling but discussing,
because they are unable to consider what's said by separating it
out into its forms. They pursue contradiction in the mere name
of what's spoken about, using eristic, not dialectic, with one another."