When one considers probabilities in important decisions, they encounter a severe pain in the marrow of their psyche. It is a kind of excruciating thought that drives itself into you, and it may be the case that the thought is your being.
There have been philosophers who insist that the most substantive of things and processes in the world are the result of our mind, which seems preposterous until one notices that the "substances" that we encounter are not only made mostly of empty space; they are substantially form and almost nothing more, except perhaps movement. This form is the greatest substance; it seems to be well described as a kind of motion, and the motion moves into itself a kind of pain when the need for a decisive understanding arises.
One does well in considering the probabilities of one's actions - the result of their in-substantive thoughts - but knowledge of them drives one mad.