Like nearly all Buddhist teachings, there are practices you can do to develop these faculties. For example, you can reflect that all beings have at one time or another been your mother, or your child; realizing this, how can you feel hatred towards any other being? It doesn't work for me, of course; I don't believe in rebirth.
Yeah, I don't buy the "remembering past lives" business, but "life after death" seems like a physical certainty if you're not necessarily attached to the "self"[1]. I suppose it's sort of how life works, on our planet anyway, for the last two billion years when we invented sex to outpace the viruses. Some sort of sentient planetary slime mold might have different ideas. One thing that's interesting is that Indian phi…
It's been described to me as a pathetic, insignificant thing, absolutely in need of a defender. Western (or I should say, english-speaking) Buddhist teachers call it "ego", but I'm pretty sure that's wrong, in that Freud and Jung coined the term "ego" (they had different definitions, but it's not the self from Buddhism that either of them defined).