The exercise is practised when he retires for the night and is lying in the dark. He goes backward in time and recalls all that has happened during the day--the persons he has met, the places he has visited, and what he has done. The picture should be made as fully detailed as possible and cover the entire field from the moment he awoke in the morning until the moment he lay down to begin the exercise. If he has talked with others, he notes the particular tone and accent of their voices, as well as hearing the sentences themselves. He tries to insert as many little items into his visualization as will render it sharp, realistic, and convincing. Out of this background he selects those of his actions and words, as well as those of his feelings and thoughts, which call for amendment or correction or discipline. He is to cull out of the day's episodes and happenings not only what his conscience or judgement tell him call for corrective work in meditation but also what is most significant for his spiritual purpose and what is likely to prove most fruitful for his creative work in meditation.
-- Notebooks Category 4: Elementary Meditation > Chapter 4: Meditative Thinking > # 244