A belief is a propensity to act as if a thing were true. Our actions—and, in some cases, our reactions—are a guide to our true beliefs. A relativist’s natural response when evil strikes close to home will usually betray her. She says she rejects morality, but in reality she still believes in it. Her actions tell the true story.
— Greg Koukl and Francis Beckwith, from Relativism: Feet Firmly Planted in Mid-Air, p. 147