Page:Popular Science Monthly Volume 77.djvu/54

43 heightened in dreams. Every impression reaches sleeping consciousness through this emotional atmosphere, in an enlarged form, vaguer it may be, but more massive. The sleeping brain is thus not dealing with actual impressions—if we are justified in speaking of the impressions of waking life as "actual"—even when actual impressions are being made upon it, but with transformed impressions. The problem before it is to find an adequate cause, not for the actual impression but for the transformed and enlarged impression. Under these circumstances symbolism is quite inevitable. Even when the nature of an excitation is rightly perceived its quality can not be rightly perceived. The dreamer may be able to perceive that he is being bitten but the massive and profound impression of a bite which reaches his dreaming consciousness would not be adequately accounted for by the supposition of the real mosquito that is the cause of it; the only adequate explanation of the transformed impression received is to be found (as in a dream of my own) in a creature as large as a lobster. This creature is the symbol of the real mosquito. We have the same phenomenon under somewhat similar conditions in the intoxication of chloroform and nitrous oxide.

The obscuration during sleep of the external sensory channels and the checks on false conclusions they furnish is not alone sufficient to explain the symbolism of dreams. The dissociation of thought during sleep, with the diminished attention and apperception involved, is also a factor. The magnification of special isolated sensory impressions in dreaming consciousness is associated with a general bluntness, even an absolute quiescence, of the external sensory mechanism. One part of the organism, and it seems usually a visceral part, is thus apt to magnify its place in consciousness at the expense of the rest. As Vaschide and Piéron say, during sleep "the internal sensations develop at the expense of the peripheral sensations." That is indeed the secret of the immense emotional turmoil of our dreams. Yet it is very rare for these internal sensations to reach the sleeping brain as what they are. They become conscious not as literal messages, but as symbolical transformations. The excited or laboring heart recalls to the brain no memory of itself but some symbolical image of excitement or labor. There