During a twenty-four hour cycle you move through these states on a bigger scale, but you also move through them in each moment. Your whole life is a movement through these three states – and through many, many lives you have moved through these three states.
The moment of death happens in sushupti, the deep-sleep state. A dying person first enters from the waking state to the dream state, then from the dream state he enters the deep-sleep state – and death happens only in the deep-sleep state. Hence, the people of ancient times have called the sleep that happens each day a mini-death. They have understood sleep to be a small glimpse of death.
Sleep is a glimpse of death. When you are in sushupti you are in the same state as when death happens, or can happen. Death cannot happen outside the state of sushupti. This is why in sushupti you lose all perception; you don’t even perceive the pain of death. Otherwise, death is a very surgical operation; there is no greater surgical operation than death.
A surgeon gives you an injection of morphine if he has to operate or remove even a small bone. By injecting morphine he forces you into sushupti: only then can the small bone be surgically removed; otherwise it is not possible. All surgical operations are done when a person is in sushupti, deep sleep. And until sushupti has overtaken you, it is dangerous to operate because an operation causes such unbearable pain that it would become difficult to perform the operation.
Death has always been the greatest surgery because the whole life has to be removed from the body. So death happens only in deep sleep. Birth also happens in sushupti: that’s why you don’t remember it. And the only reason that you have no memory of your past lives is that there is such a profound state of deep sleep between two lifetimes that all memory is lost at both ends. Death happens in deep sleep, and rebirth also happens in deep sleep.
In the mother’s womb, the child is in sushupti, deep sleep. A child who is not in sushupti in the mother’s womb will start to influence the mother’s dreams. Some children are in the dream state while in the mother’s womb. Very rarely, very few – maybe one in a million – are sometimes in the dream state in the mother’s womb, but this is a child whose previous death happened in the dream state. In Tibet, much work has been done on this: they call it Bardo.
In Tibet, they try to stop a dying person from moving into deep sleep. If he slips into deep sleep, he will lose all memories of this lifetime. So to make it possible for the person to be able to keep the memories from this lifetime, they do some special experiments near a dying person. In those experiments, an effort is made to keep the dying person awake – not only to keep him awake, but to induce a dream in him that will continue, so that death can happen to him in that dream state. If a person dies in the dream state, in his next life he will be born with all the memories of his previous life.