In reply to pebbles:
> (In reply to Milesy) how do you know? by your definition you only know about the people who have gone public! if they just contribute quietly without telling anyone you wont know, will you.
Altruism is not about whether you tell anyone or not. Altruism is doing something without a payoff.
There is a school of thought that there is no true altruism because at the very least, the payoff is that you enhance your self image, even if no one else knows.
Personally, unless you decribe altruism as 'doing something for others with only the self satisfaction it brings' then I do not think it exists.
That isn't to say there is anything wrong with getting something back. It makes me happy to help someone out. What's wrong with that?