Is it really selfless? It certainly is an extreme example, but if you consciously decide to give your life to save someone else, isn't the other option always worse? Are we saving a loved one because of our love for that person, because of our principles ... or because we couldn't bear a life without this precious person (and a life of blaming ourselves)?

I was going to make this exact point, but I was approaching quitting time at work (yes, you can tell what kind of work week I've had) and I didn't want to look so insensitive as to think that there is no good in the world without selfishness. I was willing to concede that one example as a selfless act, but in reality, deep down, there's selfishness in that, too. Just part of being human.