The issue of human coexistence is dealt with from Heidegger's point of view. Ortega y Gasset's viewpoint is also briefly considered, Man and People in particular [Course 1949-1950]. Relevance is given to the immediate and regular way in which human beings interrelate in everyday life. Its pre-re-flexive character is highlighted. However, there are also references to ways of living that transcend those modes. Considerations on the subject are focused on Being and Time and Heidegger's works preceding this book and preparing its publication. Although to a lesser extent, later books by the author are also taken into account, such as Zollikon Seminars. Special attention is given to the assumptions of the Einfhlung ("empathy") theory.