Games change, ideas remain.
It is possible to classify chess ideas by their types, genera and species.
Establishing this classification will clarify the art of chess and help its study.

Having studied a huge number of different games played during my long chess career, I have identified several types of mistakes that recur over and over again.
All these mistakes have a psychological basis.
Familiarity with them is interesting both from the point of view of an in-depth study of chess creativity and from a practical point of view.