That desire is manifested during sleep there can be no doubt; and Mr. Stewart, although insisting as he does on the distinction between this faculty and volition, confounds them in his remarks already quoted. A person suffering from nightmare has a most intense desire to escape from his imaginary troubles. In my own dream, to which reference has been made, my desire to restrain myself from crawling over the precipice was exerted to the utmost; but the will could not be brought into action. Darwin,[64] when he says that in nightmare “the _desire_ of moving the body is painfully exerted, but the _power of moving it, or volition_, is incapable of action till we awake,” makes the proper distinction between desire and will; but, as I have already shown, confounds the latter with another very different faculty. From the foregoing observations it will be seen that during sleep the three great divisions of the mind are differently affected. 1. Feeling, embracing sensation and emotion, is suspended, so far as the first is concerned; but is in full action as regards the second. We do not see, hear, smell, taste or enjoy the sense of touch in sleep, although the brain may be aroused into activity and we may awake through the excitations conveyed to it by the special senses. The emotions have full play, unrestrained by the will and governed only by the imagination. 2. The Will or Volition is entirely suspended. 3. The Thought or Intellect is variously affected in its different powers. The imagination is active, and the memory may be exercised to a great extent; but the judgment, perception, conception, abstraction, and reason are weakened, and sometimes altogether lost. CHAPTER V. THE PHYSIOLOGY OF DREAMS. The subject of the foregoing chapter is so intimately connected with the phenomena of dreaming, and I have expressed my views in regard to it at such length, that but few psychological points remain to be considered in the present discussion. What I have to say, therefore, in regard to the physiology of dreaming must be read in connection with the chapter on “_The State of the Mind during Sleep_,” in order that the whole matter may be fully understood.