Years ago, an author I respect, Joe Straczynski, in one of his postings on the Internet, stated his opinion that Mark Twain's autobiography was the greatest work in the English language. With a recommendation like that, I promptly bought and read the book. I'm not a writer, have never been an English major, and there are still quite a few books in English that I haven't read, so I cannot say whether or not I agree with Joe. I can say that I found it an excellent book.
Mark Twain was no stranger to the death of loved ones, and he did us the courtesy of writing eloquently about his experiences. His recountings give the inexperienced some understanding of what is to come, and provide the experienced with some company in their pain. And with his credentials in such matters established, he saw fit to share, from the safety of his own grave (for he had insisted that certain portions of his autobiography not be published until he was dead, or dead for some particular number of years) his own view of death. Though it flies painfully in the face of many established beliefs (a pain Twain regrets), it has stuck with me, and I pass it along for the benefit of any kindred souls.
From chapter 49 of The Autobiography of Mark Twain, as edited by Charles Neider, pages 326 to 327:
[...] I have long ago lost my belief in immortality—also my interest in it. I can say now what I could not say while alive—things which it would shock people to hear; things which I could not say when alive because I should be aware of that shock and would certainly spare myself the personal pain of inflicting it. When we believe in immortality we have a reason for it. Not a reason founded upon information, or even plausibilities, for we haven't any. Our reason for choosing to believe in this dream is that we desire immortality, for some reason or other, I don't know what. But I have no such desire. I have sampled life and it is sufficient. Another one would be another experiment. It would proceed from the same source as this one. I should have no large expectations concerning it, and if I may be excused from assisting in the experiment I shall properly be grateful. Annihilation has no terrors for me, because I have already tried it before I was born—a hundred million years—and I have suffered more in an hour, in this life, than I remember to have suffered in the whole hundred million years put together. There was a peace, a serenity, an absence of all sense of responsibility, an absence of worry, an absence of care, grief, perplexity; and the presence of a deep content and unbroken satisfaction in that hundred million years of holiday which I look back upon with a tender longing and with a grateful desire to resume, when the opportunity comes.
[Update of March 9, 2009] I agree with Alison in Austria's critique of the quote above. Nothing can be experienced of nothingness, so it is a blatant failure of logic when, at the end, Twain claims experiences of the nothingness prior to his birth – the same nothingness that he asserts will follow his death.
Personally, when I read that quote, I assume that the failure wasn't lost on Twain; that in his mind he did equate death with annihilation, and the result of annihilation with nothingness, but that he decided that it was simpler, and/or more effective from a literary standpoint, to express his perspective by ignoring the logical failure of attributing qualities to nothingness. I further assume that he trusted the readers who accepted the death-is-annihilation view to see through his sophistry, while trusting everyone else to be sufficiently offended to move on to the next paragraph without further ado.
Of course, that's a lot of assuming, and I could be wrong. I'll just add that I don't associate Twain with clumsy thinking, while I am aware (because he tells us so in his autobiography) that he was not above toying with the facts in his stories when he thought the stories would benefit. In this case, he may have been toying with the logic of the piece in order to make it easier for his readers to wrap their minds around a concept (absolute nonexistence) that might be unfamiliar to them, and/or antithetical to their beliefs. If so, it was a dubious tactic, because it conflated incompatible concepts (nonexistence and existence), and that leaves us to guess about what he really thought.
Granting all of those problems, I must admit that I still enjoy that passage every time I think of it.