Chapter 50 — That the natural desire of the separate substances is not set at rest in the natural knowledge they have of God

Now it is not possible that the separate substance’s natural desire rest in such a knowledge of God.

For whatever is imperfect in a species seeks to acquire the perfection of that species: thus someone who has an opinion about a matter, which is imperfect knowledge about it, is spurred for this very reason to the desire for certain knowledge about it. Now the aforesaid knowledge—which separate substances have about God without knowing his substance—is an imperfect kind of knowledge, for we do not deem ourselves to know a thing if we do not know its substance: so that the chief point in knowing a thing is to know what it is. Therefore, this knowledge which the separate substances have about God does not set their appetite at rest, but spurs it on to the vision of the divine substance.

Again. The knowledge of effects excites desire to know the cause: hence men began to philosophize because they sought the causes of things. Therefore, the desire for knowledge naturally implanted in all intellectual substances does not rest unless, knowing the substance of effects, they know also the substance of their cause. Consequently, since separate substances know that God is the cause of all the things whose substances they see, their natural desire does not rest unless they see God’s substance also.

Besides. As there is a connection between knowing the adequate cause (propter quid) of a thing being so and so, and knowing that it is so (quia est), so is there a connection between knowing about a thing what it is (quid est), and knowing that it exists (an est). If we know the adequate cause of a thing being so and so, we can prove that it is so (for instance, that the moon undergoes eclipse). Even so, if we know what a thing is, we can prove that it exists. Such is the teaching in 2 Posterior Analytics. (Posterior Analytics 2.1.) Now we observe that those who know that a thing is so and so naturally seek to know the adequate cause of its being so. Therefore, those who know that a thing exists naturally seek to know what it is; and this is to know its essence. Therefore, the natural desire for knowledge is not set at rest by the knowledge of God whereby it is known that he exists.

Further. Nothing finite can set the intellect’s desire at rest. This is proved from the fact that the intellect, given any finite object, strives to go beyond it. Thus, given a finite line of any length, it strives to apprehend a longer, and it is the same in numbers (and this is the reason why we can add indefinitely to numbers and mathematical lines). Now the excellence and power of any created substance is finite. Therefore, the intellect of a separate substance is not satisfied with knowing separate substances, however excellent they be, but still tends by its natural desire to understand the substance which is of infinite excellence, as we proved in the first book (Ch. 43.) concerning the divine substance.

Moreover. Just as there is a natural desire for knowledge in all intellectual natures, so is there in them a natural desire to rid themselves of ignorance or nescience. Now separate substances, as stated, (Ch. 49.) know in the manner already mentioned that God’s substance is above them, and above everything that they understand. Therefore, they know that the divine substance is unknown to them. Therefore, their natural desire tends to understand the divine substance.

Besides. The nearer a thing is to its end, the greater the desire with which it tends to that end: hence we may notice that the natural movement of bodies is increased towards the end. Now the intellect of separate substances is nearer to the knowledge of God than ours: consequently, they desire to know God more intensely than we do. And however much we know that God is, and other things mentioned above, (Ch. 49.) we still go on desiring, and seek to know him in his essence. Much more, therefore, do separate substances desire this naturally: consequently, their natural desire is not satisfied with the above-mentioned knowledge of God.

Hence we conclude that the ultimate happiness of a separate substance does not consist in the knowledge whereby it knows God by its own substance, since its desire still leads it on to the substance of God.

It also clearly follows from this that ultimate happiness is to be sought nowhere else but in an operation of the intellect, since no desire leads us so high as the desire of knowing the truth. For all our desires, whether of pleasure or of anything else that man wants, can be satisfied with other things, but the aforesaid desire rests not until it has reached God, the supreme cause and maker of all. Hence wisdom rightly says: I dwelt in high places, and my throne was in a pillar of cloud (Sir 24:4): and it is said that wisdom by her maids invites to the tower (Prov 9:3). They should blush, then, who seek man’s happiness in the lowest things, whereas it is placed on such a height.