All the greatest blessings are a source of anxiety, and at no time
should fortune be less trusted than when it is best; to maintain
prosperity there is need of other prosperity, and in behalf of the
prayers that have turned out well we must make still other prayers. For
everything that comes to us from chance is unstable, and the higher it
rises, the more liable it is to fall. Moreover, what is doomed to perish
brings pleasure to no one; very wretched, therefore, and not merely
short, must the life of those be who work hard to gain what they must
work harder to keep. By great toil they attain what they wish, and with
anxiety hold what they have attained; meanwhile they take no account of
time that will never more return.