 there is a hypothesis. And a hypothesis is a statement that you want to see if it works out. And the hypothesis is, if there is a soul that is fundamentally non-physical, but exists as real as the hand, as the foot, as anything else, if there is a soul that is fundamentally non-physical, then it should be able to do things, such as know things, perceive things, that the physical body cannot do. And so you give it a test.