"If a man steal an ox or a sheep and kill it or sell it, five oxen shall
be given in restitution for one ox, and four sheep for one sheep" (Exod.
xxii. 1). From this observe the value put upon work. For the loss of an
ox, because it involves the loss of labor, the owner is recompensed with
five oxen; but for the loss of a sheep, which does no work, he is only
recompensed with four.
THE TALMUD, _Bava Kama_, fol. 79, col. 2.