Against Celsus 2.60

Then, as if this could happen, I mean that someone should have a vision of a dead man as living, he adds like an Epicurean that someone “dreamed in a certain state of mind, or, according to his own wish, had a vision in deluded fancy,” and reported such a thing, “which,” he says, “has happened to countless people.” Even if this seemed to be very cleverly said, it nonetheless establishes a necessary doctrine: that the soul of the dead subsists, and that one who has embraced this doctrine has not believed in vain in the soul's immortality, or at least its survival; as Plato too says in his work on the soul that “shadowy apparitions” of those already dead have appeared to some people around tombs. The “apparitions” that occur concerning the soul of the dead arise from something that really exists, from the soul subsisting in what is called the luminous body. Celsus, not wishing this, will have it that some people dream even while awake and, according to their own wish, have visions in deluded fancy. It is not unreasonable to believe that this happens in a dream; but that it happens while awake to those who are not wholly out of their minds, delirious, or melancholic is not credible. Celsus foresaw this and said the woman was frantic, which the recorded story, from which he takes his accusation, does not suggest.