I would guess a person’s life circumstances. Humans tend to reflect pain they’re experiencing onto others. If you’re hungry, that’s a form of pain. If you’re neglected, that’s a form of pain. Even the sons of billionaires experience pain, probably in a way that’s hard for reg folks to grasp.

Also, I think your dopamine regulation being all messed up might also contribute. Those people who seem to flail and rage because nothing can seem to satisfy them.

Also, everyone does terrible things and hurts others. You can be charitable and kind from one perspective and an oppressor in ways you won’t allow yourself to see. We all do it.

A lot of those shitty things aren’t normal in humans, but become much more common if you force them into violent, existential conflicts.

And insatiable greed is promoted as good at almost every level of neoliberal society, so that one should be self-explanatory.

People just say “human nature” as an excuse for their own conservatism

The anthropologist Sarah Blaffer Hrdy has theorized that empathy and altruism are acquired in early childhood by observing when one’s caretakers show empathy towards oneself, which both gives infants a sense of security in interacting with other people and which, because babies learn through observation and pattern recognition, establishes a standard in their minds that tells them humans are supposed to be selfless and kind to one another. This theory is relevant to us because, since most of us live in decaying neoliberal hellholes, many people’s parents are too busy working to give them appropriate care during their formative years and are not rich enough to pay for people who are qualified to do so in their stead. When it comes to people whose parents are rich, the selfishness that lead to them accumulating wealth could get passed on to their children by the same method. In other words, the conditions created by capitalism could be fucking with the ability of infants to become good people later in life

I think it’s all about empathy.

The ability to experience empathy, like any other trait varies at the biological level (and probably other levels as well). It only makes sense some would be born with little ability to experience empathy, some with so much empathy they worry about ants, but most people in the middle.

Those with little empathy (and therefore little sympathy or compassion, as those come from empathy) don’t allow morality to restrain their behavior so they tend to rise to power.

Most of the world’s problems are because people who are effectively psychopaths are in charge everywhere. The psychopaths have created a world through capitalism that pits us against each other and brings out the worst in us.