Dreams, as we all know, are very curious things: certain incidents in them are presented with quite uncanny vividness, each detail executed with the finishing touch of a jeweller, while others you leap across as though entirely unaware of, for instance, space and time. Dreams seem to be induced not by reason but by desire, not by the head but by the heart, and yet what clever tricks my reason has sometimes played on me in dreams!
Fyodor Dostoyevsky, Notes from Underground
dreams