478 PHYSIOLOGY CHAP. 



The analogy between the psychical structure of dreams and that 

 of pathological mentation was next taken up by Cabanis, Lelut, 

 and Moreau of Tours. The delirium of dements resembles a 

 waking dream, just as the dream is the delirium of sleep. Hence 

 we may reasonably consider dreams to be temporary madness. 

 There is nothing in the phenomena of dreams that is not met with 

 in the insane : predominance of visual and auditory hallucinations, 

 exaggeration of memory, imaginary satisfaction of desires and 

 aspirations, forced association of ideas, weak reasoning, loss of ideas 

 of time and personality. 



Alfred .Maury, the eminent Hellenist, studied this subject at 

 various times (1848-1878) and made a minute comparative 

 analysis of dreams and the phenomena of insanity, in order to 

 define their psychical allinity. I Teams, like the ideas of the 

 insane, are, according to Alaury. less incoherent than would appear 

 at first sight : only the links between the ideas operate by irrational 

 associations and by analogies that elude, us on awaking. The 

 extreme volubility of some insane persons betrays an acceleration 

 of the psychical current which also characterises dreams. Jfi/per- 

 /iiti'-xi/i and i>n rn in ni'x'm are to be noted in madness and in the 

 dreams of sleep. Finally, in dreams according to Maury we 

 encounter all the symptoms of insanity. 



In forming an adequate conception of the origin of dreams we 

 must remember that our senses are not equally in abeyance in 

 sleep, and that their normal functional equilibrium no longer 

 exists; certain faculties disappear, others are exaggerated and to 

 this the dream is due. It arises from the hallucinations which 

 Maury termed hypnagogie; its formative elements are usually 

 memories, sensorial images, phrases, or impressions, acquired 

 when we are awake, which present themselves in consciousness 

 when the mind is no longer under rigid control and is unable to 

 resist the incursion of fantastic sensations. 



Another theory of dreams was put forward by Sigisniund 

 Freud of Vienna (1880). Starting from the law of causality, which 

 governs the world of thought as it does the physical world, he 

 applied it further to dream life. A dream, whatever it may be, is 

 always the result of causes that pre-existed in the waking life ; it 

 is always a combination of elements that form part of our mental 

 life, and finds its explanation in some previous psychical activity 

 of the subject. The control which we exert over our acts and the 

 course of our thoughts when awake is relaxed during sleep ; the 

 desires we seek to repress in the waking state have free play in 

 dreaming. Oneiric representations often run counter not merely 

 to the laws of logic, but also to the ethical principles of the 

 individual. 



When awake our thoughts follow in a sequence determined 

 by certain connections of time or space, by suggestions or relations 



