Life must be understood as the result of evolution, and human life as the emergence of the species Sapiens from the genus Homo of the family of apes. If the emergence of human life as an evolutionary fact is coupled with the notion of social life, we are referred to the constructive production of human life forms, of which social participation is an integral part. On the one hand, participation is tied back to the phylogenesis of the species Sapiens, but on the other hand, it has to be newly acquired and practiced by every human being in the process of ontogenesis, depending on the environment. Participation in old age is a separate specification of the conditions of this process and can be illustrated on the basis of a large number of empirical findings. This book is a translation of an original German edition. The translation was done with the help of artificial intelligence (machine translation by the service DeepL.com). A subsequent human revision was done primarily interms of content, so that the book will read stylistically differently from a conventional translation.