In the article, several mutually connected features of Ancient Greek mentality are dealt with on the material of various pieces of literary tradition. The Sleep (Hypnos) and the Death (Thanatos) are called brothers by Hesiod. Sleep is connected with dreams, and typical Greek dreams, to judge for instance from Artemidorus’ Oneirocritica, are in many cases rather unlike our modern dreams. If the latter have, according to Freud, a “censorial” function, in Greek dreams such a function was not highly developed.