Chrispimis wrote
"Well, you're leading on to a separate discussion.........."
and then went on to give a very elegant exposition of reciprocal altruism. I once held to this tenet myself, but came up against several areas of concern.
1) For reciprocal altruism to be significant it must be a favoured genetic trait. The holders of this successful mutation gained an advantage, and thus what started as a mutation became the norm. Along with many other similar proposals this proposition is entirely qualitative, nobody can show you the gene(s) in question, we must just take it on trust. A social biologist can get away with this while a chemist, physicist, earth scientist etc. would be laughed out of court if they suggested an analogous proposal.
2) One thing that evolutionary biologists rarely, if ever, tackle is competing adaptations. For example while group a) was doing just fine with reciprocal altruism, maybe some of its members had stronger arms. maybe group b) had a more efficient digestive system while group c) was developing immunity to malaria, which one was the fitter and why? I await the biologist who can resolve this conundrum.
3) Reciprocal altruism, in the absence of pure altruism, must act at the level of the individual's group/family, rather than on a species-wide level. So calling a spade a dirty great shovel, what we have here is a recipe for further speciation arising from human beings. This is but a short distance from providing legitimacy for racism, if one views races as differing gene pools or proto-species.
So the differences between us are now clear.
1) I believe that there is an absolute moral law. Consequently rape, for example, has been, is and always will be wrong. You, in contrast, believe that morals are subjective.
2) I believe that pure altruism, derived from free will, exists and that this can operate on a human race-wide scale. You in contrast believe that altruism only exists in a reciprocal form with all of the limitations that this implies.