Retrospection is contemplation of the past. Pythagoras of Samos (570-495 B.C.), the first to be called a “philosopher” (i.e. “lover of wisdom”), recommended the following exercise of retrospection before going to sleep:
"Never suffer sleep to close thy eyelids, after thy going to bed,
Till thou hast examined by thy reason all thy actions of the day.
Wherein have I done amiss? What have I done? What have I omitted that I ought to have done?
If in this examination thou find that thou hast done amiss, reprimand thyself severely for it;
And if thou hast done any good, rejoice.
Practice thoroughly all these things; meditate on them well; thou oughtest to love them with all thy heart.
'Tis they that will put thee in the way of divine virtue."
(Golden Verses of Pythagoras, 40-46)
After Pythagoras, the Greek Stoic philosophers recommended similar practices. Epicteus (c. 50-135 A.D.) wrote:
"Let sleep not come upon thy languid eyes Before each daily action thou hast scann'd; What's done amiss, what done, what left undone; From first to last examine all, and then Blame what is wrong in what is right rejoice."
(Epicteus, Discourses, 3.1)
Seneca the Younger (c. 4 B.C. - 65 A.D.) wrote about Quintus Sextius, a Roman philosopher whose philosophy combined Pythagorean and Stoic thought:
"When the day was over and he had retired to his nightly rest, he would put these questions to his soul: "What bad habit have you cured to- day? What fault have you resisted? In what respect are you better?" Anger will cease and become more controllable if it finds that it must appear before a judge every day. Can anything be more excellent than this practice of thoroughly sifting the whole day? And how delightful the sleep that follows this self- examination - how tranquil it is, how deep and untroubled, when the soul has either praised or admonished itself, and when this secret examiner and critic of self has given report of its own character! I avail myself of this privilege, and every day I plead my cause before the bar of self. When the light has been removed from sight, and my wife, long aware of my habit, has become silent, I scan the whole of my day and retrace all my deeds and words. I conceal nothing from myself, I omit nothing. For why should I shrink from any of my mistakes, when I may commune thus with myself?
"See that you never do that again; I will pardon you this time. In that dispute, you spoke too offensively; after this don't have encounters with ignorant people; those who have never learned do not want to learn. You reproved that man more frankly than you ought, and consequently you have, not so much mended him as offended him. In the future, consider not only the truth of what you say, but also whether the man to whom you are speaking can endure the truth."
(Seneca, On Anger)
Why is retrospection helpful?
The most obvious purpose of retrospection is ethical perfection.
Retrospection gives us more control of ourselves. As Seneca points out, we will have more control of our actions if we know we will review them every day. We will also become more mindful of our actions. Retrospection prepares the mind for mindfulness.
The practice of retrospection trains the mind to identify with observer of the thoughts, emotions, and physical impulses, rather than feeling victim to them.
Among the Pythagoreans, retrospection also served the purpose of training the memory. Pythagoras was said to be able to recall in backward sequence everything he had done and said throughout his day, even for several days.
During our waking hours, we engage in many activities and interactions, and we respond to them in a number of ways. Sometimes we respond with the rational, intellectual mind. Other times we are moved by our emotions or by the instinctual impulses of the physical body. A nightly exercise of retrospection could include questioning whether we acted out of the mind, emotions, or body in each event or interaction.