In its simplest form,
life after
death is a contradiction in terms. Death is by definition the end of a life, so life after death is like
dehydrated water. Yet many people insist that this physical incarnation is just part of a larger existence, that
death is not the end for them as an individual.
hope clouds observation
– Bene Gesserit Reverend Mother Gaius Helen Mohaim
The human
ego is a psychological construct designed to promote the survival and interests of its host organism. It has a hard time imagining a stage without itself on it as an actor. We find it difficult to imagine ourselves not existing. By design, the ego never gives up, never sees its situation as hopeless.
The concept of "Life after Death" is widespread, perhaps even universal to human cultures. Some claim that your soul joins the ancestral spirits. Some claim that after an intermission or bardo, the soul is recycled into a new life. Some like the ancient Egyptians, believe that the persons acts are judged or weighed, and then rewarded or punished in an afterlife, or become one with some form of God or universal spirit.
A man's ethical behaviour should be based effectually on sympathy, education, and social ties and needs; no religious basis is necessary. Man would indeed be in a poor way if he had to be restrained by fear of punishment and hope of reward after death."
Albert Einstein, "Religion and Science", New York Times Magazine, 9 November 1930
All of these
theologies serve
political ends in the
life before death. They keep people in line.
Belief in ancestral spirits promotes a conservative society, with countless generations of ancestors looking over your shoulder. Reincarnation gets the complication of karma: your status in the next life is determined by your actions in this one. Born poor? You must have deserved it, so just be humble and don't rock the boat, and maybe you'll be born rich next time. Heaven and Hell serve much the same social purpose.
So to add it up: there are good reasons why people refuse to believe that they will just die, and there are good reasons why human societies encourage and channel these beliefs, and neither of the two sets of reasons involve any actual life after death.
If you want to get to the truth, you can't base your ideas on wishful thinking. Life after death is something for which there is no evidence, no suggested mechanism, and nothing is explained by positing it. Occam's Razor does the rest.