As a religion and a philosophy, Buddhism has always stressed the importance of squarely confronting the reality of death. Death, along with illness and aging, is defined in Buddhism as one of the fundamental sufferings that all people must face.
Because of this emphasis, Buddhism has sometimes been associated with a pessimistic outlook on life. Quite the opposite is, in fact, the case. Because death is inevitable, any attempt to ignore or avoid this most basic reality of life condemns us to a superficial mode of living. A clear awareness and correct understanding of death can enable us to live without fear and with strength, clarity of purpose and joy.
Buddhism views the universe as a vast living entity, in which cycles of individual life and death are repeated without cease. We experience these cycles every day, as millions of the some 60 trillion cells that comprise our bodies die and are renewed through metabolic replacement. Death is therefore a necessary part of life, making possible renewal and new growth. At the time of death our lives return to the vast ocean of life, just as an individual wave crests and subsides back into the open sea. Through death, the individual, fundamental life-force that supports our existence, returns to the great universe. Ideally, death can be experienced as a period of rest, like a rejuvenating sleep that follows the struggles and exertions of the day.
Buddhism asserts that continuity persists through the cycles of life and death, and that, in this sense, our lives are eternal. As Nichiren wrote: "When we examine the nature of life with perfect enlightenment, we find that there is no beginning marking birth and, therefore, no end signifying death."
In the fifth century C.E., the great Indian philosopher Vasubandhu developed the "Nine-Consciousness Teaching" that delineates the eternal functions of life. In his theory, the first five layers of consciousness correspond to the five senses` and the sixth to waking consciousness. The sixth layer of consciousness includes the capacity for rational judgment and the ability to interpret the information supplied by the senses.
The seventh layer of consciousness is referred to as the mano-consciousness and corresponds to the subconscious described in modern psychology and is where our profound sense of self resides.
Beneath this is the eighth, or alaya-consciousness.The eighth layer of consciousness contains potential energy, both positive and negative, created by our thoughts, words and deeds. This potential energy, also described as profound life-tendency, is referred to as karma.
Again, contrary to certain assumptions, Buddhism does not consider karma to be fixed and unchangeable. Our karmic energy, which Buddhist texts describe as the "raging current" of the alaya-consciousness, interacts with the other layers of consciousness. It is at this deepest level that human beings exert influence upon one another, on their surroundings and on all life.
It is also at this level that the continuity of life through cycles of birth and death is maintained. When we die, the potential energy which represents the "karmic balance sheet" of all our actions—creative and destructive, selfish and altruistic—continues to flow forward in the alaya-consciousness. It is this karma that shapes the circumstances in which the potential energy of our lives becomes manifest again, through birth, as a new individual life.
Finally, there is the ninth level of consciousness. This is the very source of cosmic life, which embraces and supports even the functioning of the alaya-consciousness. The purpose of Buddhist practice is to stimulate and awaken this fundamentally pure amala-consciousness, or wisdom, which has the power to transform the most deeply established flow of negative energy in the more shallow layers of consciousness.