That seems to be this: http://en.wikipedia.org/wiki/Ethical_egoism - which I would classify as some kind of moral philosophy.

It seems to be much more biologically realistic than utilitariaism. Utilitarianism appears to be an ethical system based on clearly signalling how unselfish and nice you are. The signal seems somewhat tarnished by being pretty unbelievable, though. Do these people really avoid nepotism and favouring themselves? Or are they kidding themselves about their motives in the hope of deceiving others?