Tough for an atheist to answer this question in any depth. I usually default to my wife’s answer, “we rejoin the nitrogen cycle.” But it seems like something more is called for, so let me lay out why I’m not moved by most of the discussions of life after death.
Alright, a couple of points.
First, if we’re going to talk about life after death, I’m only interested if it means I get to experience it. I’m not trying to be selfish, I’m just trying to make the point that if something that is not me survives, like some mindless “spark of life” or shard of the infinite that loses all individuality, then I don’t care because that’s not really me that is surviving.
What does have to survive? Let’s be clear that I am the whole of my being: my thoughts, my memories, my personality and so one. I see those things as interwoven, so I don’t believe that I could drink from the river of Lethe and really still be me. My experiences, retained in my memories, shape my personality and make up who I am.
Second, some background: many members of my family suffer from mental illnesses. I’ve become very familiar with the effects of lithium and other such substances. I know that a sprinkle of this chemical and a pill of that chemical can completely alter someone’s personality. I’ve learned that we are material, and that who we are is chemistry.
I’m open to the idea that the material is not all there is. But whatever your theory for the spiritual aspects of humanity, it has to explain my relatives and their experiences. Further, it has to explain all the evidence we have that the physical brain gives rise to our minds. Under the euphemistic heading of “natural experiments,” there are hundreds of cases where accidental damage to the brain has altered a person’s perceptions, memories, personality, emotions – the whole self.
Finally, the verdict: I do not see how the being that I am could survive the shutdown of the system that my personality arises from. I cannot fathom how there could be a life after death that would be consoling or meaningful. I’m open to suggestions, but I don’t understand how we can get beyond the above points.