But how do we know humans are acting on an actual selfless decision and not instinctual behaviour? There is some evidence that, in some situations at least, our body/instinct can act first and we just end up rationalizing that we wanted to perform those actions to ourselves, as we are performing them. But that’s a bit of a thought experiment, the truth is, it’s very hard to know. And we can show empathy in very abstracted situations as well, where instinct is probably less of a factor.