Some of our greatest inventions and discoveries have been worked out by the subconscious mind during sleep. Many an inventor who went to sleep with a puzzled brain, discouraged and disheartened because he could not make the connecting link between his theory and its practical application, awoke in the morning with his problem solved.
Mathematicians and astronomers have had marvelous results worked out while they slept, answers to questions which had puzzled them beyond measure during their waking hours. Writers, poets, painters, musicians, all have received inspiration for their work while the body slumbered.
Many people attempt to explain these things on a purely physical basis. They attribute the apparent phenomenon to the mere fact that the brain has been refreshed and renewed during the night, and that, consequently, we can think better and more clearly in the morning. That is true, so far as it goes, but there is something more, something beyond this. We know that ideas are suggested and problems actually worked out along lines which did not occur to the waking mind. Most of us have had experiences of some kind or another which show that there is some great principle, some intelligent power back of the flesh, but not of it, which is continually active in our lives, helping us to solve our problems.
One of the most interesting instances of this kind is given in the biography of the great scientist, Professor Louis Agassiz, by his widow:
"He [Professor Agassiz]," the writer says, "had been for two weeks striving to decipher the somewhat obscure impression of a fossil fish on the stone slab in which it was preserved. Weary and perplexed, he put his work aside at last, and tried to dismiss it from his mind. Shortly after, he waked one night persuaded that while asleep he had seen his fish with all the missing features perfectly restored. But when he tried to hold and make fast the image it escaped him. Nevertheless, he went early to the Jardin des Plantes, thinking that on looking anew at the impression he should see something which would put him on the track of his vision. In vain—the blurred record was as blank as ever. The next night he saw the fish again, but with no more satisfactory result. When he awoke it disappeared from his memory as before. Hoping that the same experience might be repeated, on the third night he placed a pencil and paper beside his bed before going to sleep.
"Accordingly, towards morning the fish re-appeared in his dream, confusedly at first, but at last with such distinctness that he had no longer any doubt as to its zoölogical characters. Still half dreaming, in perfect darkness, he traced these characters on the sheet of paper at the bedside. In the morning he was surprised to see in his nocturnal sketch features which he thought it impossible the fossil itself should reveal. He hastened to the Jardin des Plantes, and, with his drawing as a guide, succeeded in chiseling away the surface of the stone under which portions of the fish proved to be hidden. When wholly exposed it corresponded with his dream and his drawing, and he succeeded in classifying it with ease."
We are all familiar with examples of the marvelous feats performed by somnambulists. They will get up and dress while fast asleep, lock and unlock doors, go out and walk and ride in the most dangerous places, where they would not attempt to go when awake. Many have been known to walk with sure feet along the extreme edges of roofs of houses, on the banks of rivers, or close to the edge of precipices, where one false step would precipitate them to death. They will speak, write, act, and move as if entirely conscious of what they are doing. A somnambulist will answer questions put to him while asleep and carry on a conversation rationally.
In this respect the state of the sleep walker is similar to that of a person in a hypnotic trance. He can be acted on from without and remain wholly unconscious. Surgical operations have been performed upon a hypnotized person without the use of anesthetics; and there is no doubt that this also would be possible during profound sleep. The subjective mind is much more susceptible to suggestion when the objective mind is unconscious. There is no resistance on account of prejudice or external influences.
That we are on the eve of marvelous possibilities of treating disease during sleep there is not the slightest doubt. The same is true of habit forming, mind changing, of mind improving, of strengthening deficient faculties, of eradicating peculiarities and idiosyncrasies, of neutralizing injurious hereditary tendencies, of increasing ability. The possibilities of changing the disposition and of mind building during sleep are only beginning to be realized.
The power of the subjective mind over the body is well illustrated by the fact that thoughts aroused in a hypnotized person can very materially shift the circulation of the blood. They can send it at will to any part of the body. The hypnotist can make his subject blush or turn pale, express in his face fierce anger or appealing love. He can at will produce anesthesia in any part of the body so that a needle or knife may be inserted in the flesh without causing the slightest pain. He can so impress the hypnotized person's mind with the belief that the water he drinks is whiskey that he will actually exhibit all the appearance of drunkenness. He can make him believe that the spoonful of water he takes is full of poison so that he will immediately develop the symptoms of poisoning.