I can't say with anything like certainty that I know what happens to us when we die. To some extent I think it might be a bit like the reverse of what happened at birth, only a bit more rapidly and drastically.
Of course, what happens at birth is itself an interesting question; after all, fetuses are viable before birth, capable of living without the womb. You have to go back a number of weeks to find a fetus that can't survive on its own. What's intriguing is that you don't get signs of coherent awareness, of a stringing together of consciousness into the narrative that calls itself I, until well after the baby has come into the world.
Death, on the other hand, can be abrupt. It can just as easily be a gradual process, one that happens slowly enough for everyone to get used to the idea. I have a feeling that gradual deaths are easier for the loved ones to deal with.
From another perspective, though, we're really dying all the time, in the sense that the person I was a minute ago - or an hour or a day ago - is not the same as the person that I am now. Even relatively minor events have changed my perspective, so it can be argued that the past me is dead in one sense. However, there is history, there is a continuity, there is that continuing motion of consciousness whose entire job is to join together discrete, disparate events and sensations into a beaded string of apparent wholeness.
There's a reason for all this philosophy in this post.
If the emergence of personality is an ongoing process, logically it can be traced backward until you start unweaving the roots of that personality. I've done that with a couple of things in myself, specifically my intellectual curiosity and my sense of humor. There are two other things I can trace pretty readily. One is my interest in the German language and culture; the other is my love of Godzilla movies.
I went to Berlin (still West Berlin, back then) when I was 5 years old. I don't recall a whole heck of a lot from that trip, as you might expect, though I was struck by the odd sounds of European sirens, the cramped bustle of the U-Bahn (Unterstrassenbahn, subway), the old world architecture, and the way that commercial products were different from their American counterparts. There's a lot more, but it doesn't bear repeating here. The point is that in later years these experiences and impressions would serve to fuel my interest in taking German language classes, since it is the language of my ancestry, at least on the distaff side. We went there to visit my maternal great-grandparents.
Godzilla movies, on the other hand, descended from my paternal lineage. They're terrible, of course; not only are the dubbed voices famously awkward and hopelessly mismatched, but the effects are truly bad. The stories are thinly written morality plays cautioning humans against hubris, and usually have a dash of anti-radiation panic thrown in for seasoning. And the monsters ... well. Just guys in rubber suits. But that's the point. Imagine, just imagine, that you report for work each day, put on a goofy (if uncomfortable) costume, and spend the morning stomping the crap out of intricately detailed balsa wood miniature buildings. If that's not a working definition of joy, I'm not sure what is.
It was my maternal grandmother who led me to Germany and a greater appreciation of my heritage there, and it was my paternal grandmother who first subjected me to Godzilla. (That was in a movie theater in Needles, Calif., when I was 8 or so; she sat beside me and cheered "Go get 'em, Godzilla," laughing as loudly as I did, having a hell of a good time.) These discrete aspects of my personality did not exist before those two women brought them into my life, and those two women are dead now. They died within a month of each other, this year.
In neither case was it a surprise. There had been time for everyone to be aware of what was happening, and to prepare for it as best we could. In this regard, I believe we were fortunate. I don't imagine I was better prepared than anyone else.
Buddhism has a couple of different ways of looking at death - at least, the canonical versions of Buddhism do. One view holds that there's something remarkably akin to reincarnation. This view is prevalent with Tibetan Buddhist variants in particular. The other view uses the term rebirth instead of reincarnation. The difference is subtle; in rebirth, personality is not passed into another body, just tendencies or patterns of behavior. With reincarnation, something akin to a soul is passed along instead.
Both of these views owe their existence at least in part to where Siddhartha Gautama spent his life. The Indus River valley is the cradle of Hinduism, which teaches the doctrine of reincarnation. However, another key teaching in Buddhism is impermanence, which logically must preclude the notion of a soul. So Buddhists might have to tread a very careful line, balancing the idea of rebirth or reincarnation against a philosophy that essentially undermines the very idea.
I don't believe in either reincarnation or rebirth. I don't see any way by which either could be possible. So from my perspective, my grandmothers are not merely dead; they aren't even around in essence any more, being born into another body; nor are they sitting on a cloud, harps in hands, knitting their brows and tsk-tsking at how thoroughly wrong I am. The standing waves of their lives have troughed and ebbed, leaving behind wet sand and slowly fading footprints.
Nonetheless, they persist in other ways, through my DNA, and through the tendencies and preferences they passed to me by example and instruction. This is, ultimately, all that any of us can leave behind. The extemporaneous German language instruction from one, the love for gooey butter cake from the other - these are moments we'd shared, events that continue to ripple through the froth of time into the present through my consciousness, impressions of which I pass along to others here. Eventually my own standing wave will break on the shore of time as well, and still others will recall being affected by some event or other from my own existence. This is as close to rebirth as I know how to come.
Despite my nonbelief in gods or souls, though, I find myself at ease with these deaths, recent though they both are. That's because I was fortunate enough to encounter a philosophy that allowed me to understand something important about life - or more accurately, something about the way I perceive it. That shift in perception, encapsulated in the second noble truth*, was left behind some 2500 years ago, and continues to alter the human sphere of experience today.
And rather than fill me with a sense of hopelessness or defeat, I find myself experiencing things more keenly and more vitally now, particularly when I ponder the big questions - such as how a million-Mark banknote came into my possession; or how I continue to be filled with glee every time Godzilla flattens another pagoda.
It is my wish that we may all truly understand how ephemeral human existence is, and comport ourselves appropriately in that understanding.
* Roughly, that dissatisfaction, unhappiness and suffering are rooted in the belief that anything is eternal, permanent, or unchanging.
I was primed for Buddhism - all unawares - by the same grandmother who gave me Godzilla, by the way. Spending part of my childhood summers visiting her and my grandfather, I would watch the old TV series Kung Fu. Many years later, watching the show again, I was struck at how completely its blatantly Buddhist evangelism had saturated my consciousness. The lessons from that series are still relevant, despite the way David Carradine broke his own wave on the shore.