gradually becomes so rubbed down and blunted by long
habituation to such impressions that things have a constant tendency
to produce less and less impression upon us as they pass by; and this
makes time seem increasingly less important, and therefore shorter in
duration: the hours of the boy are longer than the days of the old
man. Accordingly, time goes faster and faster the longer we live,
like a ball rolling down a hill. Or, to take another example: as in
a revolving disc, the further a point lies from the centre, the more
rapid is its rate of progression, so it is in the wheel of life; the
further you stand from the beginning, the faster time moves for you.
Hence it may be said that as far as concerns the immediate sensation
that time makes upon our minds, the length of any given year is in
direct proportion to the number of times it will divide our whole
life: for instance, at the age of fifty the year appears to us only
one-tenth as long as it did at the age of five.

This variation in the rate at which time appears to move, exercises a
most decided influence upon the whole nature of our existence at
every period of it. First of all, it causes childhood--even though it
embrace only a span of fifteen years--to seem the longest period of
life, and therefore the richest in reminiscences. Next, it brings it
about that a man is apt to be bored just in proportion as he is young.
Consider, for instance, that constant need of occupation--whether it
is work or play--that is shown by children: if they come to an end
of both work and play, a terrible feeling of boredom ensues. Even in
youth people are by no means free from this tendency, and dread the
hours when they have nothing to do. As manhood approaches, boredom
disappears; and old men find the time too short when their days fly
past them like arrows from a bow. Of course, I must be understood to
speak of _men_, not of decrepit _brutes_. With this increased rapidity
of time, boredom mostly passes away as we advance in life; and as
the passions with all their attendant pain are then laid asleep, the
burden of life is, on the whole, appreciably lighter in later years
than in youth, provided, of course, that health remains. So it is that
the period immediately preceding the weakness and troubles of old age,
receives the name of a man's _best years_.

That may be a true appellation, in view of the comfortable feeling
which those years bring; but for all that the years of