“An eye for an eye” in Ex20 is listed along with “a life for a life.” Rabbis understand the former as compensation and the later as corporal punishment. Moreover, they imagine two modes of compensation: the loss of value as a slave (a lost eye, hand, or leg) or the payment one would accept for a given suffering (a bruise). Such widely diverse reading within the same verse is implausible. It is also unworkable. A slave without a hand or leg, and probably even one without an eye, is worth zero; a slave’s leg is valued essentially as his life.

Rabbis assert that inflicting proportional damage is impossible: a 20 percent loss of vision is hard to reciprocate exactly. But the same is true of compensation: valuing any particular loss of vision is arbitrary to the point of reducing judgment to the judge’s whim. In case of reciprocal damage, at least we try to inflict it in a way that resembles the original damage; with compensation, the punishment is entirely arbitrary. Additionally, compensation brings up a question familiar from civil law: whether it should be valued according to the offender’s scale or the victim’s? Imagine a situation in which a rich person struck a pauper: presumably, the pauper would accept very little to take his bruise, but so small a compensation wouldn’t deter the rich person; naturally, we would value the compensation according to the offender’s scale. Now reverse the situation: a pauper strikes an affluent lady; he can only afford an amount totally insignificant to her; here, we’re inclined to value according to the victim’s scale. People have different amounts of wealth, but the same number of eyes.

The rabbinical retort that “an eye for an eye” is unjust to a man with one eye is nonsense: every law has its marginal cases, and the number of single-eyed people is far less than the number of abnormally rich or poor. The rabbinical argument follows the logic of Korah, whom they despise. Criticizing Moses’ laws, Korah brought a marginal case of a widow with a single goat; according to the strict sense of Jewish laws, she would end up giving her entire property to the priests. Like any legal system, Jewish law leaves marginal cases to the discretion of judges, and the unavoidable existence of such cases is no reason to strike down Jewish laws of vengeance.

If anything, the lawgiver tends to made the laws harsher. In Exodus 20, “an eye for an eye” only applies to the harm done to pregnant women, but in Deut19 it is expanded onto all criminal acts. Rabbis accept that “a life for a life” means a death sentence, a point made clear in Num35, “For blood lays guilt on the land, and the land won’t be expiated except by the blood of the one who spilled it.” Rabbis, however, effectively abrogated the death sentence by erecting impossible rules of evidence.

The rabbinical understanding of “an eye for an eye” as compensation is a face-saving measure. Pharisaic rabbis always lacked criminal jurisdiction: before the Temple’s destruction it lay with their Sadducean enemies, and after the calamity it rested with Roman magistrates. Rabbis only had jurisdiction in civil matters, and accordingly reinterpreted criminal punishment as monetary damages.