What gnaws at me most about the obvious mutuality between altruism and selfishness is that I have never been a black or white type thinker. I thrive on grey areas. They appeal to my creative side, and feed my "soul". I understand that altruism and selfishness make the world go around and that altruism is just another way of getting what one needs, (the "Art of Selfishness"). But I would like to think of the human species as having evolved beyond mere instinct and rationality towards what Nietche called "the will to power"; taking instinct to its' "highest power". Jung saw this as a contradiction, as do evolutionists, I assume. But is there not more to humans than what is finite, rational, measurable. Thomas Moore points out that "every person is infinitely more vast in scope than appears to the naked eye". And C. S. Lewis contends that "man not only lives, but loves and reasons". And Jung talks about the human call to "individuation" (wholeness). Are humans, in fact "unique" and "obligated to overcome their origins". Or are we just breeding machines.
Merton talks of the "soul" qualities of humans that give "order to our experience". I propose that humans are "unique", and that we have evolved beyond simple rationality, and that "morality" consists of the everyday choices that we make, and the reasons that we make them.
Altruism --- granted, it is most often self-serving. And while it certainly promotes cooperation, breeding, and fitness, humans do, occasionally, give of themselves, out of a sense of compassion. If the pleasant feeling that occurs as a result of that reaching-out is a form of selfishness, then so be it. But, could it also indicate that humans may have evolved beyond claw and tooth, towards heart and soul, rare as it may be. If not, then "love" is non-existent, and emotions are useless.