Since ancient times man tried to understand the roots of his obviously often irrational behaviour. According to the prevailing "Zeitgeist", hypotheses for it ranged from demonical possession, psychological schools of thought to the role of transmitter substances at the synaptic level. For ages it has been observed and described, that men goes in his development through typical and predictable phases with their typical crises. Poets knew and wrote about it since the dawn of culture but science got interested in it only in this century. Elliot coined the term "midlife crisis" in 1965, turning attention to an age-group which was before practically ignored by psychology. He pointed out that due to a collision between developmental factors and a static identity a crisis occurred in human beings, characterized by a feeling of despair, goallessness, fatigue and consciousness of significant basic anxiety. In response to such pressures a change of comportment takes place which puzzles the people closest to the stricken. Established patterns of behaviour seem to dissipate in favour of unusual, unexpected, adolescent or even crazy actions. Many examples from history, ranging from Dante to Gauguin seem to prove the point. Realizing the presence of the crisis and its origin and interpreting it as a call for change, reorientation and new definition of priorities present a great chance to adjust one's life at this important turn. It is of great importance to recognize, that changes must take place in one's inner values and that trying to escape into frenzied activities leads nowhere.(ABSTRACT TRUNCATED AT 250 WORDS)