What surprised me is the idea of a phantom limb and that they actually exist. Well, in the mind they do. Once can actually "feel" their lost limb, probably due to the trauma of losing said limb. It's interesting, too, because no one has really found a real reason why one would feel a phantom limb. There are hypotheses and ideas of how a phantom limb was formed in the mind, but there is no definite answer. It is what one can say, a mystery of life.