[I]t is to be borne borne in mind, in regard regard to the philosophical sciences, that the inferior sciences neither prove their principles nor dispute dispute with those who deny deny them, but leave this to leave this to a higher science; whereas the highest of them, viz. metaphysics, can dispute dispute with one who denies denies its principles, if only the opponent opponent will make some concession; concession; but if he concede concede nothing, it can have no dispute dispute with him, though it can answer his objections. Hence Sacred Sacred Scripture, Scripture, since it has no science above itself, can dispute dispute with one who denies denies its principles only if the opponent opponent admits some at least of the truths obtained obtained through divine divine revelation; thus we can argue argue with heretics from texts in Holy Writ, Writ, and against those who deny deny one article of faith, we can argue argue from another. another. If our opponent opponent believes nothing of divine divine revelation, there is no longer any means means of proving the articles of faith by reasoning, but only of answering his objections if he has any against faith. Since faith rests upon infallible infallible truth, and since the contrary contrary of a truth can never be demonstrated, demonstrated, it is clear that the arguments brought against faith cannot be demonstrations, demonstrations, but are difficulties that can be answered.