I recently had a discussion about the different schools of thoughts on ethics and morality and your statement definitely covers one of the 5 but there are also other ways which are perfectly acceptable.. e.g. utilitarian
Ehh, the only reason I'm unsure about this is because there's no way to define what "hurts" somebody. Technically everything we do has some kind of affect on somebody and can be interpreted as "hurting" them.
Sometimes the more ethical thing causes harm. This is the ol' train track and 5 vs 1 hostage debate.
Maybe. What you're looking at is consequentialism. There are also different schools of ethics, like Kant's philosophy. Ultimately, we don't really have a way to "judge" morality.