Primitive peoples believe that hair， nail clippings， and lost teeth remain magically linked to the owner even after they have been disconnected from his body. As any voodoo artist will tell you， if you want to grind someone into powder， you don't need to touch him at all. It's quite enough to stamp on a missing molar and let "contagious magic" do the rest. This is why peoples all over the world traditionally hide lost body parts， lest they fall into the wrong hands.
远古时期的人们认为毛发、剪下的指甲和脱落的牙齿即使离开了人的身体，仍与其主人保持着神秘的联系。正如任何一个伏都教大师都会告诉你的，假如你想置某人于死地，根本用不着去碰他，只需用脚踩碎那人脱落的一颗臼齿就够了，剩下的事就交给“无边的法力”去办。这就是为什么全世界各个民族都习惯于把身体上脱落的东西藏起来，以免落入恶人之手。
American children's ritual of hiding lost teeth under their pillows probably derives distantly from this practice. But there is an obvious difference， for when Suzie conceals her baby milk-tooth， she fully expects it to be found， and by a good magician， not an evil one. Moreover， she expects to be paid for having surrendered it， and at the going rate. Nothing mare clearly suggests the blithe commercial gusto of our culture than this transformation of a fearful superstition into a cheery business transaction.