Man is nothing but a subject full of natural error that cannot be eradicated except through grace. Nothing shows him the truth, everything deceives him. The two principles of truth, reason and senses, are not only both not genuine, but are engaged in mutual deception. The senses deceive reason through false appearances, and, just as they trick the soul, they are tricked by [the soul] in their turn: it takes its revenge. The senses are disturbed by passions, which produce false impressions. They both compete in lies and deception.
Pascal, Pensées (1987:42)