Summa contra Gentiles1.58 Chapter LVIII. That God does not understand by composition and division

It may also be shown from the same principles that the divine intellect does not understand after the manner of a composing and dividing intellect. For He knows all things by knowing His essence. Now He does not know His essence by composition and division; since He knows Himself as He is, and in Him there is no composition.? Therefore He does not understand by way of a composing and dividing intellect.

Again. Things composed and divided by the intellect are by nature such as to be considered by the intellect apart from one another: for there would be no need of composition and division, if from the very fact that one understood what a particular thing is, one knew what is or is not in that thing. Therefore if God understands by way of a composing and dividing intellect, it follows that He sees all things, not at one glance, but each one separately: and yet we have proved the contrary above.

Further. In God there cannot be before and after. Now composition and division come after the consideration of what a thing is, for this consideration is their foundation. Therefore composition and division are impossible in the divine intellect.

Again. The proper object of the intellect is what a thing is: wherefore about this the intellect is not deceived except accidentally; whereas it is deceived about composition and division; even as the senses are always true about their proper objects, but may be deceived about others. Now, in the divine intellect there is nothing accidental, and only what is essential. Wherefore in the divine intellect there is no composition and division, but only simple apprehension of a thing.

Moreover. The composition of a proposition formed by a composing and dividing intellect exists in the intellect itself, not in the thing that is outside the mind. Wherefore, if the divine intellect were to judge after the manner of a composing and dividing intellect, His intellect would be composite. But this is impossible as shown above.

Again. A composing and dividing intellect judges of various things by various compositions: because the composition of the intellect does not go beyond the limits of composition: wherefore the intellect does not judge that a triangle is a figure by the same composition whereby it judges that man is an animal. Hence, if God considers things by composing and dividing, it follows that His act of understanding is not one only but manifold. And thus again His essence will not be one only, since His intellectual operation is His essence, as we proved above.

Yet we must not therefore say that He is ignorant of enunciations. For His essence, since it is one and simple, is the type of all things multiple and composite: so that thereby God knows every multitude and composition both of nature and of reason.

Holy Writ is in agreement with this. For it is said (Isa. lv. 8): For My thoughts are not your thoughts.’ And yet it is said in the psalm:? The Lord knoweth the thoughts of men, which manifestly proceed from composition and division of the intellect.

Moreover. Dionysius says (Div. Nom. vii.): Wherefore divine Wisdom, by knowing itself knows all things, the material immaterially, divisible things indivisibly, multitude unitedly.