Truth conformity to fact.
1. It has been distinguished by most philosophical writers, according as it respects being, knowledge, and speech, into
(1.) Veritas entis, or truth of the thing. The foundation of all truth is in truth of being--that truth by which a thing is what it is, by which it has its own nature and properties; and has not merely the appearance, but reality, of being. Philosophy is the knowledge of being; and if there were no real being — that is, if truth could not be predicated of things — there could be no knowledge.
(2.) Veritas cognitionis, or truth of knowledge. Truth, as predicated of knowledge, is the conformity of our knowledge with the reality of the object known; for, as knowledge is the knowledge of something, when a thing is known as it is that knowledge is formally true. To know that fire is hot is true knowledge. Objective truth is the conformity of the thing or object known with true knowledge.
(3.) Veritas signi, or truth of the sign. This consists in its adequateness or conformity to the thing signified. The truth and adequacy of signs belong to enunciation in logic.
2. Scientific truth consists in the conformity of thoughts to things; and moral truth lies in the correspondence of words with thoughts; while logical truth depends on the self-consistency of thoughts themselves.
3. Truth, in the strict logical sense, applies to propositions, and nothing else; and consists in the conformity of the declaration made to the actual state of the case. In its etymological sense, truth signifies that which the speaker believes to be the fact. In this sense it is opposed to a lie, and may be called moral. Truth is not infrequently applied to arguments, when the proper expressions would be "correct," "conclusive," "valid." The use of truth in the sense of reality should be avoided. People speak of the truth or falsity of facts; whereas, properly speaking, they are either real or fictitious. It is the statement that is true or false.
4. Necessary truths are such as are known independently of inductive proof; are those in which we not only learn that the proposition is true, but that it must be true; are those the opposite of which is inconceivable, contradictory, impossible. Contingent truths are those which, without doing violence to reason, we may conceive to be otherwise.
5. Absolute truth is the knowledge of God, the ground of all relative truth and being. All relative truth is partial because each relation presupposes something which is not relative. As to us relative truth is partial in another sense, because the relations known to us are affected by relations which we do not know, and therefore our knowledge even as relative knowledge is incomplete as a whole and in each of its parts. At the same time, relative knowledge is real knowledge; and if it were possible habitually to realize in consciousness that it is partial, it would be strictly true so far as it goes. See Blunt, Dict. of Hist. Theol. s.v.; Fleming, Vocab. of Philos. Sciences, s.v.
6. In Scripture language, eminently, God is truth; that is, in him is no fallacy, deception, perverseness, etc. Jesus Christ, being God, is also the truth, and is the true way to God, the true representative, image, character, of the Father. The Holy Spirit is the Spirit of truth, who communicates truth, who maintains the truth in believers, guides them in the truth, and who hates and punishes falsehood or lies, even to the death of the transgressor (Ps 31:5; Joh 14:6,17; Ac 5:3, etc.).
Especially is truth a name given to the religion of Jesus, in opposition to that of the Jew and that of the heathen. As contrasted with the Jewish system, it was the "truth" in the sense of "reality," as distinguished from the "emblems," symbols, representations, of that reality; from the "shadow of good things to come," contained in the Levitical law in this sense it is that the apostle tells us "the law was given by Moses, but grace and truth came by Jesus Christ." As contrasted with paganism, Christianity was truth opposed to falsehood. The heathen mythology not only was not true, but was not even supposed as true: it not only deserved no faith, but it demanded none. Jesus inaugurated a new way of propagating a religion, by inviting converts not to conform to its institutions, but to "believe" and to to let their actions be agreeable to truth: nothing, then, was more natural than that Christianity should receive names expressive of this grand peculiarity, the truth and the faith. See Whately, Essays on Difficulties of St. Paul, essay 1.