Such retrospective analyses, critical evaluations, and impersonal interpretations of his past must be attempted only in calm periods if the results are not to be emotionally distorted. Against this rule there is nevertheless an exception. When he feels bitter self-reproach about his bygone mistakes or misdeeds, it is well to take advantage of such an anti-ego attitude while it lasts.

-- Notebooks Category 4: Elementary Meditation > Chapter 4: Meditative Thinking > # 153