The words of the language, as they are written or spoken, do not seem to play any role in my mechanism of thought. The psychical entities which seem to serve as elements in thought are certain signs and more or less clear images which can be "voluntarily" reproduced and combined...from a psychological viewpoint this combinatory play seems to be the essential feature in productive thought. The elements are, in my case, of visual and some of muscular type. Conventional words or other signs have to be sought for laboriously only in a second stage, when the mentioned associate play is sufficiently established and can be reproduced at will.