You always choose sides, even if you deem yourself neutral. If you truly were, you'd never even bother getting involved in the first place.
And sometime you just choose not to do anything.
No Doctor, I'm just trying to enlighten you. I want you to see that the universe isn't as well off as you think it is. As long as you're around someone will always be in danger. Someone will always die.
[He laughs at the questions, taking a moment to clear his throat.]
Really? We've lived through genocide, war, and the like. And honestly Doctor, a companion, really? How many have we lost in the past or simply corrputed? No, I'm afraid this isn't about me.