Mainul H Khan said,

“I noted from my studies on human history that the idea of an afterlife is stemming mainly from different religious traditions. This indicates to me that the idea of an afterlife is invariably based on belief in God. 

Am I wrong? Is it possible to have a secular idea of an afterlife? If so, what kind of afterlife would that be? Would an atheist afterlife be something like a reincarnation until some scientific or material type of nirvana?”

M Samir Hossain said,

“Answering this question requires a higher level of knowledge and understanding in the subject that I do not possess. However, from my experience from the development of the Death and adjustment hypotheses (DAH), I can share a few thoughts on this.

First, to me, it is understandable that death is not our end. As a result, theoretically, any existence after death can give one the sense of afterlife whether or not the issue of God is included in it.

Second, the world we live in does not have a perceivable slot for God in it; for this world, God is invisible, even for a believer. If the afterlife is imagined similarly, you could say that afterlife is imaginable without the idea of God. Unfortunately, we do not experience death until we die, therefore rational argument about the afterlife is rather irrational unless it is purely based on some religious premise.

Third, in my understanding from DAH, the denial of the afterlife in human society is more connected to religious issues than acceptance. That is, the inner urge that encourages us to deny the afterlife is largely a reflection of our attitude towards any judgment after death. You will see different schools of thought where the idea of existence after death has been accepted without much use of the idea of a Creator.

It could be that any existence beyond death is obscured. Death is like a water surface of a deep dark abyss where we only see the reflection of the things that are above the water. As a result, all we (those that never have seen beyond this life) can rationally argue about is how death is not our end but not how an afterlife might be.”