Replying to Do you believe in the existence of pure good or evil?

Thats pretty much my question. What do you believe and why?

I dont, and heres why. I think its impossible for someone to be completely evil. Take any human being thats done something we portray as evil. Are they? Do they consistently go around making the 'evil' choice when faced with a decision? No. They do what they think is right based on what their life has taught them so far. That might have led them to complete insanity - take the virginia tech shooter for instance - but not pure evil.

So what do you think? Are there people that are truly all good or all evil? Powers that conspire that are?