We generally agree that chess is a mental sport. But what is a mental sport? I see chess as a game that involves decision making. I make a decision on the board and then you make a decision.
It is also a game of problem solving. I set you a problem and then you set me a problem. So its also about finding solutions.
So what are the natural enemies to decision making? I think it is negative thinking. Seeing the cup half empty. When you are negative, you do not make optimum decisions. This evidence is borne out in the game of chess.
The other enemies are emotions of impulsiveness, impatience, anxiety, anger, fear; the strong negative emotions as well as the strong "positive" emotions like excitement, exuberance, euphoria etc. This evidence is also borne out in the game of chess.
Decision making is also about good thinking skills. How to examine the evidence, how to select what is relevant and what is not. How to understand comprehensively, to weigh evidence and then to come to valid conclusions.
In short its about finding solutions on how to move forward in the face of ever changing circumstances. And the expression of our thinking is demonstrated by how we move our pieces on the board.
So, how come we dont teach these things? How to identify negative thinking. How to identify the ruling emotion. How to identify valid and invalid conclusions?
After all, every move/decision we make will be a reflection of all these factors.
The need is to make good decisions before the act, not review bad decisions after the fact only to repeat them again and again. It is about learning how to make good decisions in the moment.