The present book is a collection of originally independent articles which were written at different times and for quite different occasions. Hence，the reader will find some of the fundamental i-deas recurring throughout the book. The selection has been made in order to give a picture of the fields thus far studied，the psy-chology of the person and of the environment，ancl at the same time to inclicate their connections with the various applied fields，
　　especially child psychology， pedagogy， psychopathology， charac-terology，and social psychology.
　　Only a few years ago one could observe，at least among Ger-man psychologists，a quite pessimistic mood. After the initial suc-cesses of experimental psychology in its early stages， it seemed to become clearer and clearer that it would remain impossible for ex-perimental method to press on beyond the psychology of perception and memory to such vital problems as those with which psychoanalysis was concerned. Weighty "philosophical" and"method-ological" considerations seemed to make such an undertaking apriori impossible.