Cloudscape

Beyond death there are but three possibilities: either there is nothingness, or there is infinity, or there is something between the two as there is now. The first would mean to become undone; the second would mean to become one with all of existence; the third would mean to be reborn.
In the latter case, whether we are reborn in heaven or in hell or in earth, we would remain much like we are now, that is, limited. Thus we would be reborn over and over again forever, since nothing that is finite can remain the same as it is. If this cycle of reincarnations would last for an infinitely long time, it would also randomly involve an infinite amount of situations and eventually repeat them infinitely many times; if not, then it must end either in nothingness or in infinity, as it could not remain stable otherwise.
This is actually quite a horrifying possibility, since it would mean that we would end up in every possible situation we could imagine, from the most blissful to the most painful, be it in reality or in imagination. Be it through our environment or hallucinations, either how, we would go through every possible experience that could be conceived of. More frightening still, because of this we would also end up being every possible person, from the most honorable to the most cruel. In some future life we might be a murderer, or a rapist or a tyrant. Worst of all, we could do nothing about the fact that everything that would ever happen would happen again, and we could never do anything to avoid it.
As to what came before birth, likewise, there are again the same three possibilities. But here the possibility of infinity and of nothingness become harder to defend; after all, both nothingness and infinity are stable. There is nothing that defines them, and therefore no state into which they could evolve; after all, why should it evolve into one state and not another, if the starting points are identical? If we came from nothing, or came from infinity, then we would have remained either nothing or infinite.
Nothing can simply pass from nonexistence into existence; for nonexistence has no configuration whatsoever, and so cannot change into another specific configuration such as that of a human body. This would be a complete paradox: if we came from nothing at all, then there would be nothing that would determine what we would become. There would be no reason why we should be ourselves rather than someone else, and therefore who we are would be acausal. There cannot have been a beginning, neither of the universe nor of our lives within them, because something would have caused that beginning, as well; otherwise, it would just be without any reason at all.
Seen purely from our own viewpoints, how could our own consciousness one moment have not existed and then suddenly have been bound to a specified body? Since my consciousness was bound to a particular body means that it must have been defined in a particular way, but how is this possible if it had not existed before?
If we suppose that everything has a cause, then this is completely impossible; thus, our own consciousness must always have existed. This may or may not mean that if this is so, it will also always exist; after all, if our consciousness had existed for an infinitely long time, then from a purely statistical viewpoint it would appear impossible to stop existing. This is not something I say because I want to believe this, for I believe the possibility of eternal repetition is far more terrifying than that of eternal nothingness. The possibility of infinity is the only that offers some comfort, as infinity could only remain stable through infinite love.
That our consciousness never had a sudden beginning is not as far-fetched as it seems: after all, how can we place a line between consciousness and unconsciousness? Are not some of our own perceptions even now only partly conscious, that is, subconscious, and some to so little extent that we never realize they are there at all?
At what point does a fetus become conscious in the womb? Or did we already have some more fundamental consciousness still before that? Can we pinpoint an exact moment at which it becomes conscious, before which there was no consciousness at all and after which all of a sudden there was consciousness? And if so, where did the consciousness suddenly come from? Out of the blue, from nowhere at all? Or does consciousness arise gradually?
Perhaps the only solution to this question is that our consciousness has always existed; in that case, there are but two possibilities: the first is that what we are now is just another of an infinite series of reincarnations, which over time will go through every possible situation and eventually repeat themselves.
The second possibility is that our consciousness has grown for an infinitely long time. Before we were born, before our consciousness was bound to the complex system of our brain, perhaps our consciousness was bound to simpler systems. Perhaps if one would go back in time and if somehow one could observe what one's consciousness had once been, one would find that it would always halve, and halve again and over and over forever as one would go further in time; perhaps once, before we were conscious of our own bodies, we were conscious on lower levels. However, since every level of consciousness could be halved, our consciousness would have been lower and lower in the past but never have reached zero; however, it would have approached zero as a limit. That is, it would have been infinitesimal in the past; as every level of consciousness would further be halved without quite reaching zero, it could have existed for an infinitely long time. If this is true, we don't need to deal with the inexplicability of consciousness that arose from nothing to become something.
Perhaps consciousness is something that grows from an infinitesimal point to bit by bit spread over the entire infinity of the universe. Put another way, perhaps that of which we are conscious grows until it becomes the entire universe.
To live is a transitive. We are always aware of something. Right now, we are aware of our own bodies and their surroundings, perhaps, earlier, we were conscious of a single atom, and before that of a single particle and so on ad infinitum. Maybe we should not think of consciousness as something that arises from matter, but rather something that merely relies on it: we are aware of matter, and as such we could not be aware without matter as there would be nothing to be aware of; but that does not mean per se that matter causes consciousness.
If our consciousness has grown from a infinitely close to nothing over an infinitely long time, it is reasonable to assume that it will continue to grow towards infinity, though possibly never fully reaching it. In fact, relative to future, infinite levels of consciousness, our current level of consciousness would then still be infinitesimal. This is merely a question of frame of reference.
I would like to emphasize that this is merely a hypothesis, and not my personal belief. Consciousness is probably by far the most mysterious thing in the universe, and since it cannot be observed, we can only hope to understand it through pure logic. But logic, too, can be flawed. I still believe each of the three scenario's (infinity, finity, or nothing) to be possible and favor none of these; but my hopes are that we will, sooner or later, reach infinity. If we do, however, the question still remains if we will do so in a finite amount of time, or if we can only approach it over an infinitely long time.

As and when we achieve immortality, the cycle of birth and death for ourselves is terminated - but this termination is in itself part of the cycle.