If there's no God to decide what's good and what isn't good, who decides what's true and what isn't? Who decides what's right and what's wrong? In a world where God doesn't exist there can be no absolutes: there is no ultimate right or wrong except what humanity decides is so. "Good" and "bad" are entirely subjective concepts, and open to change. To paraphrase a certain president from not long ago, "Truth is fluid".