Good and evil.

This isn't the heart telling you to seek revenge; it's not at all the heart. It's that notorious egoism, that part of the soul that everyone has, and it's far from being the best part. But you can't deny that it's necessary. We're just different people – reason tells me to do everything for myself, not my heart. I don't live by impulses; I just didn't express myself well. I live with my soul. It's not very pure... actually, I don't even want to touch such filth. But it's the one that tells me how to live better without causing pain to anyone. Sorry for the rambling; I've never been good at expressing what I feel in words.