These are specific claims about the way the world is. It is only the notion that a doctrine is in accord with reality at large that renders a person's faith useful, redemptive, or, indeed, logically possible, for faith in a doctrine is faith in its truth. What else but the truth of a given teaching could convince its adherents of the illegitimacy of all others ? Heretical doctrines are deemed so, and accorded a healthy measure of disdain, for no other reason than that they are presumed to be false