[De veritate dicenda aut tacenda]

its own nature, insofar as that sign conceived in the mind is brought forth by the organ of the tongue to the ears of others. And so it is called the adequacy of the thing to the intellect. It is customary, however, to distinguish a triple truth: namely, of life, of justice, and of doctrine. The truth of life is that according to which someone lives rightly in himself, when his life is conformed and adequate to right reason. The truth of justice, however, is that according to which someone observes the rectitude of the law in judgments which are toward another, and there is also there an adequacy of his works to the law. The truth of doctrine consists in a certain manifestation of words, concerning which there is knowledge, insofar as the doctrine is adequate to good scriptures and to sayings and authorities founded in truth. Man, however, is a civil or social animal toward another; therefore, one owes to another that without which that society cannot be preserved. For men cannot live together unless they believe one another, as if manifesting the truth to one another. Those things which are in the heart ought to be manifested because one man cannot know the heart of another except through external signs. Opposed, however, to this truth is falsity or a lie, when something is announced externally which is believed internally with the intention of deceiving. And this falsity can be in deed as well as in speech. An example of the first is in the simulation of a hypocrite, when someone displays himself differently in deed than he is in his heart, existing as evil and simulating himself to be good. And this falsity of work and life is of a graver fault than the falsity of speech. It is not asked here whether it is sometimes allowed to say the false, because to say what is knowingly false is a pure lie, which in no case is licit. For "You will destroy all who speak a lie." To such a degree is a lie to be avoided that even for the sake of preserving the life of another, or so that no other might fall into mortal sin, no one ought to commit any venial sin. For no one ought to offend God so that someone else