Is all human behavior driven by selfishness? Many writers and philosophers have made that claim. But, writing at his blog at Psychology Today, Dalrymple says this idea is so simple as to be useless:
…this assertion, which is commonly made by those who pride themselves on their hard-bitten realism, is either empirically empty or blatantly false. It can be made true by definition, so that there could be no behaviour in contradiction to it. For example, if someone sacrifices his own life to save anther, it could be said that he preferred to do so rather than live with himself if he failed to do so. But this means that no evidence could ever refute the hypothesis.