Musar for Bava Kamma 166:24

Rekanati comments about this in the following words: "We know that halachically our sages understand the עין תחת עין as a demand to pay appropriate financial compensation for the organ impaired or destroyed. The same principle applies to the verse Leviticus 24,19, ואיש כי יתן מום בעמיתו, where we also find that monetary compensation is called for. The words באדם כן ינתן בו (Leviticus 19,20), mean that something that is usually passed from hand to hand is to be the means of compensation."