Slartibartfast: Perhaps I'm old and tired, but I think that the chances of finding out what's actually going on are so absurdly remote that the only thing to do is to say, "Hang the sense of it," and keep yourself busy. I'd much rather be happy than right any day.

Arthur Dent: And are you?

Slartibartfast: Ah, no. Well, that's where it all falls down, of course.

Like a thread spawned to do some work and wound down on completion like countless other threads that are also running in parallel.

Does a individual thread's identity count? May be it does may be it doesn't.