Each and every person in this world is a egoist, there i said it, plain and simple.
We only care about ourselves, be it a person who earns big bucks in a multinational company and spends it entirely on himself, or the people who work for the upliftment of the downtrodden.
Well the first one is quite simple to understand. The man makes money so that he can live a comfortable and fulfilling life. Even if he donates money he does it for his own moral upliftment( see i donated money i'am such a kind hearted and great person, because of me the poor kid is smiling). A man's ego is not just about the money, as in the second case the man satisfies his ego by working for the poor. He wants to be evaluated by others as great, or if that's not the case in his own self(i refused the big bucks offered by the company and instead i'am helping the poor). Here he boosts his ego by getting respect and recognition.
The point i'am trying to make here is "EGOIST" should not be taken in a negative sense, since it is the main reason behind the evolution of our society. Be it a scientist, entrepreneur or a social worker they all worked to boost their Ego's and see What they have achieved.
So lets accept it we all work for ourselves and ourselves only, We all are Egoistic Bastards.