Let me just note that deception is our genetic heritage. Dawkins talks about the subtle gene but the British “subtle” would be the American “deceptive”, I think. And our deception is all the more effective if we make ourselves believe it. Just to be clear, I don’t consider myself exempt by any means.
If my purpose is to help other people, then how I help other people is not really relevant. I may feed them or provide shelter or whatever. Whether I feel good about helping them is also not relevant. The main idea is that my purpose is to help them.
If my purpose is to feel good, then helping other people is similarly merely a means to achieve that end and the means is not relevant to a discussion of purpose. Perhaps helping people will make me feel good or cheating them may make me feel good or whatever. The main idea is that my purpose is to feel good.
If you do a Google search, you will find very few people who are willing to say that their purpose in life is to feel good without tying that purpose to something we find more acceptable.
We all have a great need for self worth (self esteem). We cannot get that self worth through living for our own self happiness so we tend to subconsciously invent stories about helping other people.
Sure, go ahead and copy this to your site if you like. Go ahead and use my name if you want.
You’re right about people not wanting to say that they do generous things because it makes them feel good about themselves. However, I still think that saying a goal of making the world a better place boils down to a desire to feel good about yourself is kind of like saying a goal of being a great chef boils down to a desire to not be hungry. Even if it is true in a technical sense, it is overly cynical and probably incorrect in implications.
I should also point out that a philosophy of helping others can be derived from pure self interest, whether or not the act of helping others makes you feel good or not. For example, if I would want others to come to my aid if I were injured, then I must go to the aid of the injured or be philosophically inconsistent.