The actions of the somnambulist are, doubtless, prompted and governed by those dream-impulses which the imaginary incidents passing through the sleeper's mind suggest. He is a dreamer able to act his dreams. This we learn from those exceptional cases in which the somnambulist, upon awaking, has remembered the details of his dream; in illustration of which we find an anecdote, related with much vivacity, by Brillat-Savarin, in the "Physiology of Taste." The narrator is a M. Duhagel, who was the prior of a Carthusian monastery, and he thus tells us the story: "We had in the monastery in which I was formerly prior, a monk of melancholic temperament and sombre character, who was known to be a somnambulist. He would sometimes, in his fits, go out of his cell and return into it directly; but at other times he would wander about, until it became necessary to guide him back again. Medical advice was sought, and various remedies administered, under which the paroxysms so much diminished in frequency, that we at length ceased to think about them. One night, not having retired to bed at my usual hour, I was seated at my desk occupied in examining some papers, when the door of the apartment, which I never kept locked, opened, and I beheld the monk enter in a state of profound somnambulism. His eyes were open, but fixed; he had only his night-shirt on; in one hand he held his cell lamp, in his other, a long and sharp bladed knife. He then advanced to my bed, upon reaching which he put down the lamp, and felt and patted it with his hand, to satisfy himself he was right, and then plunged the knife, as if through my body, violently through the bed-clothes, piercing even the mat which supplied, with us, the place of a mattress. Having done this, he again took up his lamp and turned round to retrace his steps, when I observed that his countenance, which was before contracted and frowning, was lighted up with a peculiar expression of satisfaction at the imaginary blow he had struck. The light of the two lamps burning on my desk did not attract his notice; slowly and steadily he walked back, carefully opening and shutting the double door of my apartment, and quietly retired to his cell. You may imagine the state of my feelings while I watched this terrible apparition; I shuddered with horror at beholding the danger I had escaped, and offered up my prayers and thanksgiving to the Almighty; but it was utterly impossible for me to close my eyes for the remainder of the night.