Yes, because deciding my life is more important that a stranger's life is being so so selfish and uncaring. I'm a grade A asshole for that, eh?
Jin, the thing is I don't believe in afterlife. The fact is that nobody is guaranteed more than one life (the life we're living now...). So lif this could be the only life I get, why would I make it shorter for someone else's benefits? If I died, it's not like I would be happy with myself for such a good deed, because I couldn't feel ANYTHING for myself as I'd be non-existent.
If you want to discuss religion, just tell me but it'll make for a long read.
And firefighters do what they do because it's saving one person. They *could* die, but so could a lot of things people do. Either way in your question, one person dies, so why would I choose my life over someone else's? It's not my fault this other guy's gonna die, I look out for myself. His/her life isn't my responsibility.