Lex talionis refers to the concept of reciprocal punishment famously encapsulated in the phrase "an eye for an eye, a tooth for a tooth.” This principle is evoked in only a particular contexts in pentateuchal law (injury of a pregnant women [Ex 21:22-23]; animals, injury, and murder) but is often considered to be a principle with wider application. This type of justice is also described in the laws of Hammurabi demonstrating its antiquity. There has been some debate on whether this is a “primitive” form of justice. However, earlier codes than Hammurabi have monetary compensation which has forced reevaluation of this premise. Seen from modern, western notions inflicting physical punishment seems crude and violent, but carrying out talionic justice presupposes a central authoritarian justice system, whereas monetary compensation is more likely to occur between groups that lack such a system. Lex talionis can also be viewed as a way to limit excessive punishment by limiting the punishment in proportion to the crime. It has been argued that biblical laws elevate common Israelites to the same status since there is no differentiation in punishment for a crime based on status. This depends on how one interprets the punishment of the slave, since the master does not loose his eye. This may have been more useful to the slave than an eye-less master (or rather an angry eye-less master), but it is debatable whether Israel does divide punishment along lines of class.
Lex Talionis, ABD