It was not an unfamiliar sensation, but it was strange to feel it in the daytime. Mostly, it was a nighttime visitor, an ever-gentle gnawing at the back of the head that had to be always guarded against, lest its realization sweep forth with a cold familiar rush. It was the sudden startling glimpse over the edge—the realization that death is inevitable, that it happens to everyone, that it would happen to too; that someday, someday, the all-important (the center of the whole thing) would Would stop. Would end. Would no longer Nothing. Nobody. Finished. Death.
David Gerrold