Let him throw all his experiences into this scrupulous analysis. It does not matter whether, on the surface, they are important or not. So long as there is some instructive significance to be distilled from them, some moral lesson, philosophic principle, practical guidance, or metaphysical truth, they are grist for his mill. Most events and episodes that he can remember, the trivial as well as the tragic, are to be reconsidered from this strictly impersonal point of view and made to serve his spiritual development.
-- Notebooks Category 4: Elementary Meditation > Chapter 4: Meditative Thinking > # 192