THE EQUINOX Dreams reveal to us the sickness or the health, the calm or the disturbance, of our plastic medium, and consequently, also, that of our nervous apparatus. They formulate our presentiments by the analogy which the images bear to them. For all ideas have a double significance for us, relating to our double life. There exists a language of sleep; in the waking state it is impossible to understand it, or even to order its words. The language of slumber is that of nature, hieroglyphic in its character, and rhythmical in its sounds. Slumber may be either giddy or lucid. Madness is a permanent state of vertiginous somnambu- lism. A violent disturbance may wake madmen to sense, or kill them. Hallucinations, when they obtain the adhesion of the intelligence, are transitory attacks of madness. Every mental fatigue provokes slumber; but if the fatigue is accompanied by nervous irritation, the slumber may be incomplete, and take on the character of somnambulism. One sometimes goes to sleep without knowing it in the midst of real life; and then, instead of thinking, one dreams. How is it that we remember things which have never happened to us? Because we dreamt them when wide awake. This phenomenon of involuntary and unperceived sleep when it suddenly traverses real life, often happens to those who over-excite their nervous organism by excesses either of work, vigil, drink, or erethism. 118