Plutarch, De tranquilitate animi
W. C. Helmbold, Ed.

But that every man has within himself the storerooms of tranquillity and discontent, and that the jars containing blessings and evils are not stored ‘on the threshold of Zeus,’ ¹ but are in the soul, is made plain by the differences in men's passions. For the foolish overlook and neglect good things even when they are present, because their thoughts are ever intent upon the future, but the wise by remembrance [p. 217] make even those benefits that are no longer at hand to be vividly existent for themselves. For the present good, which allows us to touch it but for the smallest portion of time and then eludes our perception, seems to fools to have no further reference to us or to belong to us at all ; but like that painting of a man² twisting rope in Hades, who permits a donkey grazing near by to eat it up as he plaits it, so insensible and thankless forgetfulness steals upon the multitude and takes possession of them, consuming every action and success, every pleasant moment of leisure and companionship and enjoyment; it does not allow life to become unified, when past is interwoven with present, but separating yesterday, as though it were different, from to-day, and to-morrow likewise, as though it were not the same as to-day, forgetfulness straightway makes every event to have never happened because it is never recalled. For those who in the Schools do away with growth and increase on the ground that Being is in a continual flux, in theory make each of us a series of persons different from oneself³; so those who do not preserve or recall by memory former events, but allow them to flow away, actually make themselves deficient and empty each day and dependent upon the morrow, as though what had happened last year and yesterday and the day before had no relation to them nor had happened to them at all.