Disputed Questions on Truth 1.1c: Transcendental Terms

De veritate 1.1: What is truth?

It should be said that just as in demonstrable matters a reduction must be made into some principles that are per se known to the intellect, so in investigating what each thing is [a reduction must be made]. Otherwise, in each case an infinite regress will occur, and science and our knowledge of things will perish. Now, as Avicenna says in the beginning of his Metaphysics, that which the intellect first conceives as if it were the most known and that into which it resolves all of its concepts is a being. Consequently, all the other conceptions of the intellect must be had by addition to a being. But nothing can be added to a being as though it were extraneous in the way that a difference is added to a genus or an accident to a subject. For, each nature is essentially a being. Hence, the Philosopher also proves that a being cannot be a genus. But with respect to this, some things are said to add to being inasmuch as they express a mode of a being itself that is not expressed by the name of a being. This happens in two ways.

In one way such that the mode expressed is some special mode of a being; for there are different grades of entity according to which are accepted diverse modes of being (modi essendi), and according to these modes diverse genera of things are accepted. For, substance does not add a difference to a being that designates some nature superadded to a being, but by the name substance a certain special mode of being is expressed, namely, a being through itself. The same is true of the other genera.

In another way [some are said to add to being] such that the mode expressed is a general mode consequent upon every being (ens). This mode can be taken in two ways: first, according as it follows upon each being in itself; in another way according as it follows upon one being in an order in relation to another. If in the first way, this is twofold; because either something affirmative or something negative is expressed in the being (ens). We can find, however, nothing affirmative that is said absolutely and that can be taken in every being except its essence, with respect to which it is said to be. And so, the name thing is imposed, which differs from a being, according to Avicenna at the beginning of the Metaphysics, in that a being is taken from the act of being (actus essendi), but the name 'thing' expresses the quiddity or essence of a being. The negation, moreover, that is consequent upon every being considered absolutely is undividedness (indivisio), and this is expressed by the name one. For the one is nothing other than a being that is undivided.

But if the mode of a being is taken in the second way – namely, according to the order of one to another – this can be in two ways. In one way, according to the division of one from another, and this is expressed by the name something. For, something is said to be, as it were, another what. Hence, just as a being is said to be one in so far as it is undivided in itself, so it is said to be something in so far as it is divided from others. In another way according to the agreement (convenientia) of one being to another. This, indeed, cannot be unless something is accepted that by nature agrees with every being. But this is the soul, which, as is said in On the Soul 3, "in some way is all things." In the soul, however, are the cognitive and appetitive powers. The name good therefore expresses the agreement of a being with appetite. Hence, at the beginning of the Ethics it is said that the good is "that which all seek (appetunt)." But the name true expresses the agreement of a being with the intellect.

But every cognition is perfected through an assimilation of the knower to the thing known, so that assimilation is called the cause of knowledge, just as sight knows color through being disposed with respect to a species of color. The first comparison of a being to the intellect, therefore, is that a being accords (concordet) with the intellect. Indeed, this concordance is called "the adequation of thing and intellect." And, in this the notion of the true is formally perfected. Therefore, this is what the true adds to a being, namely, the conformity or adequation of thing and intellect. As we said, the cognition of a thing follows upon this conformity. In this way, therefore, the entity of a thing precedes the notion of truth, but cognition is a certain effect of truth.

Accordingly, truth or the true is found defined in three ways. In one way, [it is defined] according to that which precedes the notion of truth and according to that upon which the true is founded. And, Augustine in the book Soliloquies defines [it] thus: "The true is that which is"; and Avicenna in his Metaphysics: "The truth of each thing is a property of its being which has been established for it." Certain others [define it thus]: "The true is the undividedness of being and that which is."

[Truth] is defined in another way according to that in which the notion of the true is formally perfected. And so, Isaac says: "Truth is the adequation of thing and intellect"; and Anselm in the book On Truth: "Truth is a rectitude perceptible only to the mind" – for, this rectitude is said with respect to a certain adequation. And, the Philosopher says in Metaphysics 4 that in defining the true we say that [truth is had] when one affirms "that to be which is, and that not to be which is not."

In a third way the true is defined according to the effect that follows upon it. And so, Hilary says, "the true is that which declares and manifests being." And Augustine in the book On True Religion says: "Truth is that by which that which is, is shown"; and in the same book, "Truth is that according to which we judge about inferior [things]."