One must be clearly aware of the origin of one’s movements because there are contradictory velleities in the being—some pushing you here, others pushing you there, and that obviously creates a chaos in life. If you observe yourself, you will see that as soon as you do something which disturbs you a little, the mind immediately gives you a favourable reason to justify yourself—this mind is capable of gilding everything. In these conditions it is difficult to know oneself. One must be absolutely sincere to be able to do it and to see clearly into all the little falsehoods of the mental being.
If in your mind you go over the various movements and reactions of the day like one repeating indefinitely the same thing, you will not progress. If this reviewing is to make you progress, you must find something within you in whose light you yourself can be your own judge, something which represents for you the best part of yourself, which has some light, some goodwill and which precisely is in love with progress. Place that before you and, first of all, pass across it as at a cinema all that you have done, all that you have felt, your impulses, your thoughts, etc.; then try to coordinate them, that is, find out why this has followed that. And look at the luminous screen that is before you: certain things pass across it well, without throwing a shadow; others, on the contrary, throw a little shadow; others yet cast a shadow altogether black and disagreeable.
Ref : Questions and Answers 1950-1951