We may say adultery is wrong, but if it's a friend who we know well, who had a troubled marriage, maybe we're more forgiving. We say stealing is wrong, but we might be more understanding of our favorite politician when they're caught lining their pockets. We do this all the time.

The point is that there are lots of different contextual influences that contributes to people's moral judgments.

Morality has evolved with our species because of humans' practical and psychological need for social bonds, but even early human societies began codifying a morality into laws and norms that were meant to be applied universally.

The evolutionary origin of morality is coordination or cooperation to help people get onto the same page by pointing to common normative principles that we can use to negotiate relationships, to organize interactions across many different social contexts.

Back in evolutionary time, we didn't interact with others across the world; only with the people in our family, the people that we could see. It's because of that that we have developed these sorts of biases that have to do with social distance: we think that the harm that is being done up close and personal, right in front of us, matters more than the harm that is being done across an ocean.

So it shouldn't surprise us that the biases our minds exhibit are pragmatic. The moral judgments we make about people close to us are more forgiving and nuanced than the judgments we make of strangers.

When we examine the moral judgments of others, it's tempting to think that we live in different worlds, but there's only one. The challenge today is that our social contexts are far more global and complicated, so can our sense of tribal morality evolve to encompass people outside of our tribe?

Studying moral psychology allows us access to others' perspectives, to the fact that others could have different values, and so just knowing that there is this complex space of moral psychology could help us to understand where other people are coming from. 

We're all connected in some way. Between any two people in the world, there's some common value or experience. Finding that commonality could be the best path towards a more morally-consistent world.