There are things that can be achieved through effort, and some can’t be controlled by that. In investing, only by reading good books and articles we can experience the change of investing philosophy.
However, we can’t change our investing psychology. The old wisdom “Don’t be emotional” is something we can’t act upon easily.
Oftentimes we find that our emotion is out of our control range. Therefore it doesn’t really seem reasonable to think of directly controlling our emotion in investing.
The only way to solving it is to set up a right system of behavior, instead of directly trying to change your mind whenever it hit you like it’s a mind control game.
The idea “Don’t be focused on the daily fluctuation” can’t be achieved only through mind control, but through detailed action plan like “investing only small amount so as not to be itchy to check it every second” or “just check the stock price once a day”
Better yet, we can employ a tactic of “lowering a bar” in which we just check the price 3 times a day at a specified time.
What I am trying to say is based on different ideas than the famous idea “set up principles and stick to it”. Rather, it is about how we should deal with principles when we fail to act upon them.
Those ideas above are actually subset of principles and it has a little different nuance compared to just principles. It has reflected daily contradictory behaviors and human error when having to follow principles and adjusted principle so that it can be executed in different ways.