Simply put, compassion is more intimate. Compassion is a lowering of the conceptual barrier between oneself and another, experiencing their suffering as one’s own to some degree. The impulse to relieve that suffering is all the more compelling because it isn’t seen as being someone else’s problem. Pity is a more remote sentiment. The suffering of the other is viewed from a safe distance. One feels insulated from, and uninvolved with the sufferer. If one is moved to action at all, it’s only so as to feel magnanimous.