To understand the experience of deep sleep of another person we do not have to ask him. As soon as somebody says that he had a deep sleep we are able to understand his experience, without asking him at all. The reason we have to ask the other person’s waking and dream experiences because we are different from him in these two states. However, if anybody’s deep sleep experience is understood by us even without asking, it automatically shows that during deep sleep there is no difference at all between us; I am himself. In other words, it is clear that I exist in everybody’s deep sleep. In the waking state, we experience the world through our sense organs and mind, which are different for each individual. In dreams however, the sense organs are inactive and only the mind functions.