ABSTRACT
Following Polya (1945) I proceed from the following three assumptions: (1) “ Heuristic” means “ serving a discovery” ; (2) solving of a problem certainly contains a bit o f discovery, hence it involves heuristic processes; (3) investiga tion into heuristic processes cannot aim at finding infallible rules o f how to make discoveries; it is directed instead at comprehension of human problem-solving behavior. Accordingly, all rules and laws pertaining to problem-solving behavior are called heuristic principles. A teacher or that very person who solves a prob lem may use these rules consciously to increase the effectiveness o f the solving process. Thus we have to categorize the heuristic principles: principles o f which the subject is or is not aware; principles received from other people or worked out by oneself; principles applied with another’s help only, or without any assistance.
