Noun
An assertion of the contrary to what has been said or affirmed; denial of the truth of a statement or assertion; contrary declaration; gainsaying.
Direct opposition or repugnancy; inconsistency; incongruity or contrariety; one who, or that which, is inconsistent.
Source: Webster's dictionaryPeople more easily tolerate opposition than a contradiction. Marie von Ebner-Eschenbach
Contradiction is not a sign of falsity, nor the lack of contradiction a sign of truth. Blaise Pascal
I spoke without fear of contradiction. I simply did not suffer self-doubt. Elia Kazan
The world is a perpetual caricature of itself; at every moment it is the mockery and the contradiction of what it is pretending to be. George Santayana
Military intelligence is a contradiction in terms. Groucho Marx
He hoped and prayed that there wasn't an afterlife. Then he realized there was a contradiction involved here and merely hoped that there wasn't an afterlife. Douglas Adams