But why is it that to an old man his past life appears so short?  For this reason:  his memory is short; and so he fancies that his life has been short too.  He no longer remembers the insignificant parts of it, and much that was unpleasant is now forgotten; how little, then, there is left!  For, in general, a man’s memory is as imperfect as his intellect; and he must make a practice of reflecting upon the lessons he has learned and the events he has experienced, if he does not want them both to sink gradually into the gulf of oblivion.  Now, we are unaccustomed to reflect upon matters of no importance, or, as a rule, upon things that we have found disagreeable, and yet that is necessary if the memory of them is to be preserved.  But the class of things that may be called insignificant is continually receiving fresh additions:  much that wears an air of importance at first, gradually becomes of no consequence at all from the fact of its frequent repetition; so that in the end we actually lose count of the number of times it happens.  Hence we are better able to remember the events of our early than of our later years.  The longer we live, the fewer are the things that we can call important or significant enough to deserve further consideration, and by this alone can they be fixed in the memory; in other words, they are forgotten as soon as they are past.  Thus it is that time runs on, leaving always fewer traces of its passage.

Further, if disagreeable things have happened to us, we do not care to ruminate upon them, least of all when they touch our vanity, as is usually the case; for few misfortunes fall upon us for which we can be held entirely blameless.  So people are very ready to forget many things that are disagreeable, as well as many that are unimportant.

It is from this double cause that our memory is so short; and a man’s recollection of what has happened always becomes proportionately shorter, the more things that have occupied him in life.  The things we did in years gone by, the events that happened long ago, are like those objects on the coast which, to the seafarer on his outward voyage, become smaller every minute, more unrecognizable and harder to distinguish.

Again, it sometimes happens that memory and imagination will call up some long past scene as vividly as if it had occurred only yesterday; so that the event in question seems to stand very near to the present time.  The reason of this is that it is impossible to call up all the intervening period in the same vivid way, as there is no one figure pervading it which can be taken in at a glance; and besides, most of the things that happened in that period are forgotten, and all that remains of it is the general knowledge that we have lived through it—­a mere notion of abstract existence, not a direct vision of some particular experience.  It is this that causes some single event of long ago to appear as though it took place but yesterday:  the intervening