Deceit : the action or practice of deceiving someone by concealing or misrepresenting the truth.
Reality : the state of things as they actually exist, as opposed to an idealistic or notional idea of them.
Trust : firm belief in the reliability, truth, or ability of someone or something.
Truthfulness : the fact of being true; truth.
Fact : a thing that is known or proved to be true.
Antonym of Deceit is Truthfulness