We have evidence, of course, that other stimuli, too faint to make their presence known in the tumult of our waking hours, frequently emerge into consciousness in sleep. In this way we seem to revert in dreamful sleep to a more primitive stage of consciousness, which was ours, perhaps, far back in planetary history, before our lives were sharply divided up into alternating periods of helpless slumber and waking activity. But, though in the study of dreams we may find interesting and valuable illustrations of the working of telepathy, the demonstration of a supersensuous mode of communication between mind and mind rests primarily, as has already been said, upon the experimental results of which brief samples have been given in a previous chapter. For dream-coincidences, however striking, can in themselves afford even less support to the theory than the waking visions dealt with in the last chapter. For this evidential inferiority there are several reasons. In the first place, dreams are as the sands on the seashore in number; many persons have dreams every night of their lives. St. Augustine tells us in his Confessions that a wise friend warned him that astrology was a false science. "Of whom," said the Saint, "when I had demanded how then could many true things be foretold of it, he answered me, 'that the force of chance diffused throughout the whole order of things brought this about.'" The force of chance still operates, and undoubtedly many dream-coincidences must be attributed to normal causes. In the second place,
