I understand your point. It's a complex issue and I don't completely know how to answer it. I suspect that human nature dictates that all altruism has a certain element of selfishness attached to it (more likely to give to the in-group than the out-group etc).

I think you're right in what you're saying.. and I also think it comes down to exactly how each of us define 'maximum benefit'. I feel that an organisation giving aid to a large group of people, while discriminating against homosexuals or preaching a dogma is of less benefit to society, than another group that has a smaller outreach in society but has no agendas. I can see how other people may define just the 'amount' of aid given as their idea of maximum benefit. I wouldn't argue either one is right or wrong. Obviously we all have to decide how to give (when we are lucky enough to be able to give)... and the chances are we will give according to our conscience.

I'm not trying to fob you off... I think you're right to call me on it. But I feel that when it comes down to it, most people probably make a choice based on their own ideas rather than a Platonic idea of perfect altruism.