Aesop's

The Charger And The Miller

A CHARGER, feeling the infirmities of age, was sent to work in a mill instead of going out to battle. But when he was compelled to grind instead of serving in the wars, he bewailed his change of fortune and called to mind his former state, saying, "Ah! Miller, I had indeed to go campaigning before, but I was barbed from counter to tail, and a man went along to groom me; and now I cannot understand what ailed me to prefer the mill before the battle." "Forbear," said the Miller to him, "harping on what was of yore, for it is the common lot of mortals to sustain the ups and downs of fortune."