And what do you do? said the elderly man occupying the space next to me
Primarily, I exist. I float in space and I experience my sparse environment. My brain is active, but my body is passive. It responds only to external stimlui, of which there are none, so it remains perfectly still. My body does not wither or decay, nor does it grow. It is as it always has been, and it always will be the same. I mention this so that we can deem any discussion of it irrelevant, as while it certainly exists, it plays no meaningful part in my existence.
The world was gone. It was not remembered how or why it had gone, but it had disappeared, along with its habitats, life cycles, agriculture. With it, our lives had disappeared too. Cultures, industries, habits, quirks, relationships: when there was nothing to interact with, no interactions could take place. Idiosyncrasies were dead, but we were not. We lived on, despite the disappearance of the earth, and indeed all things in the universe. The absence of air was a shock, we soon found that there was no need to breath but it was no longer possible to talk or make sounds. We screamed empty voiceless screams at first, opening our mouths wide to cry out. I do not know when, but at some point the sun and the stars were no longer in the sky of which we could see all of, since there was no matter to block it, and without light there was nothing by which to see each other by.
I exist. My mind works perfectly, but there is nothing for me to use it for. No problems to solve, or puzzles to compute. There are no emotions because there is nothing to become emotional about. Events of the past are so far distant that if they can be remembered at all they have no meaning, not even as abstract concepts.
The elderly man next to me did not speak again. Nor had he ever spoken. He had disappeared. I may too disappear in time (if there still is such a thing, for there is no way of knowing). This thought does not bother me. I no longer hope or fear, I merely experience existence. The experience is pure.