As soon as the mind has returned into its body, which you call waking, it forgets all these adventures, and, therefore, every time of sleeping it is surprised at its separation as something new. At night you may see the minds of men rising out of their bodies as they fall asleep. All their faults remain in the body; and the minds, being free from bad inclinations, lament to each other the several imperfections of the bodies to which they are joined, earnestly desiring death to set them at liberty. The minds of rival statesmen avow to each other the plots which they are preparing, and deplore their contemptible employments. In these conversations they are apt suddenly to disappear, being summoned back into the body by waking; and when the night is over they all vanish. In the day there are a few wandering minds of those, who, like you, have been surprised by sleep through fatigue or idleness.
SLEEPER.
But whence proceed our dreams, if the sleeping body has no mind in it?
SPIRIT.
Dreams are the fancies of the mind at its first return to the body in waking, when it has lost its separate being, and is not yet quite settled in combination. These visions pass in a few seconds of time, though appearing of long duration. In reality you dream only at the time of waking.
SLEEPER.
Sleep must be the best part of human life; it is far better to be a pure spirit, and converse with heavenly beings, than to be busy in the miserable undertakings of men. Henceforth I shall obtain as much sleep as possible.
SPIRIT.
But you are to forget what now passes as soon as you are in your body again.