Keeping everything safely wrapped up is your skin. Most of us have the same kind of body parts in the same places. You have a head and a neck. You have arms, elbows, hands and fingers. You have a ...

The Bible's lex talionis – "Eye for eye, tooth for tooth, hand for hand, foot for foot" (Exodus 21:24-27) – has captured the human imagination for millennia.

Life without a toe is a nuisance. But life without a head is impossible. Might people intuitively understand that different body parts have different values? Knowing the value of body parts gives ...