DREAMS, subjective phenomena de pendent on natural causes, or trains of ideas which present themselves to the mind during sleep. The principal fea ture of the state of dreaming is the ab sence of voluntary control over the cur rent of thought, so that the principle of suggestion has unlimited sway. The ut ter want of coherency in the images that appear before the mental eye excites no surprise in the dreamer.
We dream because our brain is in a condition of partial activity. Some maintain that no sleep is ever so pro found as to be perfectly dreamless. With an over-congested brain, there is a tend ency to a rapid succession of vivid dreaming, interrupted by intervals of wakefulness. The brain cells are too excited by the excess of blood to pass into a condition of repose, and their ac tivity tends to keep up the congestion of the organ. The onset of acute disease (especially when affecting the nervous system) is not infrequently heralded by continued dreaming or continued sleep lessness. Depressing dreams should al ways be regarded as an indication of need for attention to health, or to relax ation from work, more especially, per haps, by those engaged in professional pursuits.
The special character of many dreams is determined by the conditions of the organs of the thorax and abdomen, and of the muscular system. For example, the presence of indigestible food in the stomach, by embarrassing the breathing and the action of the heart, suggests the ideas of the various forms of nightmare, the monster, or the crushing weight, from which there is no escape, which are closely akin to the sensations in duced by similar effects on the heart during the day. An uncomfortable posi
tion in bed, a strained condition of the muscular system, will cause dreams of falling over precipices or of strug. gling. Certain drugs give a specific character to dreams. The magnificent visions of the opium stupor have been made familiar by the classical account of De Quincey. Excessive indulgence in alcohol gives rise to delirious dreams characterized by unfounded dread and suspicion. Occasionally intellectual ef forts are made during sleep which it would be diffict,lt to surpass in the wak ing state Among the peoples of antiquity, dreams were regarded as direct mes sages from the spiritual world, of Either divine or diabolical origin; their inter pretation was elevated to the rank of a science. At the royal courts of Babylon and Egypt the interpretation of dreams was part of the duties of soothsayers.
Pseudo-psychologists believed that dreams are caused by the flight of the soul to other regions, and that on its re turn to the body it remembered what it had actually seen. Some persons have thought dreams the proof of the soul's immortality. This hypothesis formed the basis of the religion of Comenius and of Emanuel Swedenborg. Swedenborg strengthened the Church which he founded by his claim to have visited Paradise and his report of his experi ences there. The North American In thermometer which was named for him, and is sometimes erroneously said to be the discoverer of the telescope and mi croscope. He died in London in 1634.