Selfishness vs. Self-interest

Self-interest = Neither of us wanted a full pizza, so we split the cost and each ate half.
Selfishness = I ate all the pizza that you paid for and drank all of your beer, then I threw up on your dog.

Sometimes people way smarter than I have these really great ideas, and then they use words that have a way of advertising the opposite of what they mean. The above is an example...Self-interest is a basic human right, selfishness implies the violation of human rights - big difference. Acting in one's own self-interest is simply pursuing happiness; selfishness may also be in the pursuit of happiness, but more than implies you are doing it at someone else's expense. And I'm not just talking pizza. It goes for beer too. It is always in everyone's self-interest to enjoy my pizza and beer, but they are selfish if they take it without my consent. Selfishness leads to a sense of entitlement, which leads to plunder, which is in violation of someone else's self-interest. Since beer is not an inalienable human right (sniff), if you are drinking it for free, and no one gave it to you, it is plunder. Ay! aarg, it's PLUNDER me brothers!