“Oh, thou that sleepest, what is sleep?” asks the curious Leonardo.  Modern psychological science has little to offer of a positive nature in answer to this world-old question, but it has at least effectively disposed of the absurd theories of the materialists who would have us believe that sleep is a mere matter of blood circulation or of intoxication by accumulation of waste products in the system.  Sleep states are not abnormal, but part and parcel of the life existence of the individual.  When a person is asleep he has only become unresponsive to the mass of stimuli of the external world which constitutes his environment.  As Sidis says, “When our interest in external existence fags and fades away, we go to sleep.  When our interests in the external world cease, we draw up the bridges, so to say, interrupt all external communication as far as possible, and become isolated in our own fortress and repair to our own world of organic activity and inner dream life.  Sleep is the interruption of our intercourse with the external world:  it is the laying down of our arms in the struggle of life.  Sleep is a truce with the world.”

The twin concepts of higher space and curved time sanction a view of sleep even bolder.  Sleep is more than a longing of the body to be free of the flame which consumes it:  the flame itself aspires to be free—­that is to say, consciousness, tiring of its tool, the brain, and of the world, its workshop, takes a turn into the plaisance of the fourth dimension, where time and space are less rigid to resist the fulfillment of desire.

DREAMS

We find a confirmation of this view in dream phenomena.  But however good the evidence, we shall fail to make out a case unless dream experiences are conceded to be as real as any other.  The reluctance we may have to make this concession comes first from the purely subjective character of dreams, and secondly from their triviality and irrationality—­it is as though the muddy sediment of daytime thought and feeling and that alone were there cast forth.  In answer to the first objection, advanced psychology affirms that the subconscious mind, from which dreams arise, approaches more nearly to the omniscience of true being than the rational mind of waking experience.  The triviality and irrationality of dreams are sufficiently accounted for if the dream state is thought of as the meeting place of two conditions of consciousness:  the foam and flotsam “of perilous seas in faery lands forlorn,” whose vastitude, whose hidden life, and rich argosies of experience, can only be inferred from the fret of the tide on their nether shore—­the tired brain in sleep.