1 8 Journal of Comparative Neurology. 



The literature of the subject is enormous but with few 

 exceptions genuine scientific methods have been conspic- 

 uously absent. Either the mind has been dominated by a 

 mysticism akin to dream-life itself or the student has failed to 

 take the subject seriously. The scientific study of dreams 

 requires peculiar discipline and unusual conditions. First 

 catch your dream — and this is by no means so easy as it first 

 appears, not so much because one cannot dream at will as 

 because the tissue of a dream deliquesces on exposure to the 

 daylight of cortical consciousness. A dream melts in the warm 

 hand, it is distorted by a breath, it phosphoresces and burns 

 out in an oxygenated atmosphere, the cinder left at the ter- 

 minus of its comet-like trajectory is very unlike the actual 

 dream. A dream must be prepared by a special technique as 

 essential as parafifine imbedding for sectioning the tissues of the 

 brain which produces it. 



One must be conscious of two sets of physical environ- 

 ments. The dream association is played upon a different stage 

 and before a different audience from that of waking states. Yet 

 the drama of the day is frequently the parody of the night. 

 When one recalls a dream, especially to repeat it, the elements 

 are clothed in the language of day association and uncon- 

 sciously to ourselves we recreate the whole scene to an extent 

 which deprives it of much of its scientific value. Even when 

 one lies quietly with closed eyes and immediately upon waking 

 traces hastily on a scratch book the outlines of the dream, he 

 finds no words to express the peculiar shadowy character of his 

 dream. I am convinced that one peculiarity of the dream 

 which distinguishes it from presentations of waking experience 

 is the fact that a concept is incompletely associated with its sen- 

 suous elements. During normal states the concept of a dog 

 involuntarily associates with itself the presentations of hairiness, 

 size, bark, wagging of tail, warm breath, etc. , etc. , but the 

 dream dog may possess only the wag of the tail and be neither 

 hairy, warm or noisy. The image is like that of a triangle 

 with three angles and no sides which the geomety of dreams 

 finds no difficulty in construing. Another peculiarity of the 



