Bitch modern humans have been on this earth for six hundred thousand years creating an enormous number of distinct and unique cultures which shape the people living under them. The absolute arrogance to think you can generalize a hundred billion people's worth of experience based on what you've experienced in your one tiny lifetime. Humans are so fucking diverse there is VERY little you can say is "human nature." But no please tell me more about how people are just selfish by default despite all the fucking evidence to the contrary.
to see the real counterpoint to that argument i would highly recommend david graebers more anthropologically-oriented works (debt the first 5000 years and towards an anthropological theory of value in particular) to get an idea of just how differently human societies can see the world and just how many of our fundamental practices and assumptions that we think are 'universal' are absolutely anything but
#SwedenGate is a great example of culture at work, where the Swedes apparently have a set of practices that differ from almost every other culture on earth but have no self awareness about it.
yeah one of the things graeber talks about in towards an anthropological theory of value is how, even in the west, the relics of our prior more gift/mutual-obligation-based economies/social relations (and their conceptions of value) still exist to a substantial extent in our private spaces, and how purely market self-interest that dominates in public life coexists uneasily and appears very vulgar in many private domains of our lives. we talk about our 'values' for things that are important to us in our social relations that are an explicit rejection of self-interested market logic and the market sense of 'value' (sharing, helping those close to us, gifts, our obligations to guests and the people around us). there is of course still plenty of self-interested logic in a lot of this - the social capital from being a generous host etc etc, but it's a very different kind of logic with entirely different conceptions of what is valuable/important behind it.
and yeah swedengate is the perfect example, when this is excised within a particular culture (for whatever reason) and such an obligation doesnt exist or is denied, people act with visceral shock and revulsion even in societies awash with market ideology because we do still have a separate conception of what is important and valuable and even 'normal' that is not dictated by the 'human nature' of market relations.