It's not easy when your brain is physically incapable of considering another human as anything else than "The Other" past a certain number of people you already know.

Social animals, like humans, form groups. In turn, these groups have a natural size. Past roughly 250 people (which is the natural size of human groups) it is impossible for us to consider outsiders with the equal attention as we do with members. It is literally a different mental datum.

This is the reality which forms the context in which we need to find peace. To imagine an ideal situation that ignores this physical limitation might be pleasant but would hardly be applicable in reality.