ABSTRACT
Sleep is a result of inner adaptation in evolution and cannot be explained by scientific methods. The same holds for experience and consciousness. Sleep belongs to life as an elementary phenomenon just like wakefulness and consciousness. During sleep the actual genetic process is inhibited. The submersion in sleep is a kind of disappearance, a surrender of the self, and awakening is a kind of being reborn. A switch to sleep can originate also from the forebrain because no information about fusion can be provided. From the point of view of biosemiotics, there are paradoxes in sleep, because life itself, right from its origin, is characterized by the paradoxical principles of Eros and Thanatos. One regards REM sleep as a third elementary state of the organism, different from awakeness and different from sleep. Normally, REM sleep appears after a period of synchronized sleep.
