On Altruism, from the Stanford Encyclopedia of Philosophy.

[Voltaire2]

Do theories of the evolution of biological altruism apply to humans? This is part of the broader question of whether ideas about the evolution of animal behaviour can be extrapolated to humans, a question that fuelled the sociobiology controversy of the 1980s and is still actively debated today (cf. Boyd and Richerson 2006, Bowles and Gintis 2011, Sterelny 2012). All biologists accept that Homo sapiens is an evolved species, and thus that general evolutionary principles apply to it. However, human behaviour is obviously influenced by culture to a far greater extent than that of other animals, and is often the product of conscious beliefs and desires (though this does not necessarily mean that genetics has no influence.) Nonetheless, at least some human behaviour does seem to fit the predictions of the evolutionary theories reviewed above. In general, humans behave more altruistically (in the biological sense) towards their close kin than towards non-relatives, e.g. by helping relatives raise their children, just as kin selection theory would predict. It is also true that we tend to help those who have helped us out in the past, just as reciprocal altruism theory would predict. On the other hand, humans are unique in that we co-operate extensively with our non-kin; and more generally, numerous human behaviours seem anomalous from the point of view of biological fitness. Think for example of adoption. Parents who adopt children instead of having their own reduce their biological fitness, obviously, so adoption is an altruistic behaviour. But it is does not benefit kin—for parents are generally unrelated to the infants they adopt—and nor do the parents stand to gain much in the form of reciprocal benefits. So although evolutionary considerations can help us understand some human behaviours, they must be applied judiciously.

Where human behaviour is concerned, the distinction between biological altruism, defined in terms of fitness consequences, and ‘real’ altruism, defined in terms of the agent's conscious intentions to help others, does make sense. (Sometimes the label ‘psychological altruism’ is used instead of ‘real’ altruism.) What is the relationship between these two concepts? They appear to be independent in both directions, as Elliott Sober (1994) has argued; see also Vromen (2012) and Clavien and Chapuisat (2013). An action performed with the conscious intention of helping another human being may not affect their biological fitness at all, so would not count as altruistic in the biological sense. Conversely, an action undertaken for purely self-interested reasons, i.e., without the conscious intention of helping another, may boost their biological fitness tremendously.

Sober argues that, even if we accept an evolutionary approach to human behaviour, there is no particular reason to think that evolution would have made humans into egoists rather than psychological altruists (see also Schulz 2011). On the contrary, it is quite possible that natural selection would have favoured humans who genuinely do care about helping others, i.e., who are capable of ‘real’ or psychological altruism. Suppose there is an evolutionary advantage associated with taking good care of one's children—a quite plausible idea. Then, parents who really do care about their childrens' welfare, i.e., who are ‘real’ altruists, will have a higher inclusive fitness, hence spread more of their genes, than parents who only pretend to care, or who do not care. Therefore, evolution may well lead ‘real’ or psychological altruism to evolve. Contrary to what is often thought, an evolutionary approach to human behaviour does not imply that humans are likely to be motivated by self-interest alone. One strategy by which ‘selfish genes’ may increase their future representation is by causing humans to be non-selfish, in the psychological sense.

https://plato.stanford.edu/entries/altruism-biological/

The whole article is interesting, as is much of this internet treasure, but the closing section is relevant to some of the ongoing discussions here.