There are three stages: jagarti, svapna, susupti. Anyone has got this experience. One stage is that you are awakened, another stage is sleeping, and another stage is unconscious. Jagarti, svapna and susupti, the Sanskrit name. Jagarti, when you are awakened, our consciousness is very acute, very strong. In sleeping stage, there is consciousness, but it is not so active. And unconscious stage means consciousness is some way or other subdued, not working. Three stages. So death means that unconsciousness for a long period. That is death. Because the soul is eternal. It will be explained. There is no birth and death. So when this body is annihilated, so the soul remains unconscious for a period, seven months for a human being. Seven months unconscious stage within the womb of the mother. After seven months, the consciousness revives. Just like if you have got an experience under chloroform, unconsciousness. The surgical operation takes place, you do not understand, you do not perceive pains and pleasure, but you remains for a certain hours unconscious. Then, gradually, dream comes. Just, from unconsciousness the dream comes. And from dream, you are awakened. As you go down from awakening stage to dream, dream to unconsciousness, similarly, you come up also, from unconsciousness to dream, from dream to awakening conscious stage.
Lecture on Bhagavad-gita 2.17, London, 23 August, 1973