Do you know what perfect sincerity is?…
Never to try to deceive oneself, never let any part of the being try to find out a way of convincing the others, never to explain favourably what one does in order to have an excuse for what one wants to do, never to close one’s eyes when something is unpleasant, never to let anything pass, telling oneself, “That is not important, next time it will be better.”
Ref : Questions and Answers 1954