Summa contra Gentiles3.21 Chapter XXI. That things have a natural tendency to be like God forasmuch as he is a cause

It is clear from the foregoing that things have a tendency to be like God also in the point of their being causes of others.

For the creature tends to be like God by its operation. Now, by its operation, one thing is the cause of another. Therefore things tend to a divine similitude in this also, that they are causes of other things.

Again. Things tend to be like God, forasmuch as He is good, as stated above.” Now it is out of His goodness that God bestows being on others; for all things act forasmuch as they are actually perfect. Therefore all things seek to be like God, by being causes of others.

Moreover. Order towards good, is itself a good, as we have shown above.? Now every thing forasmuch as it is the cause of another, is directed to a good: for good alone is caused per se, and evil is caused only by accident, as we have proved.? Therefore it is a good to be a cause of others. Now in respect of any good to which a thing tends, that thing’s tendency is to a divine similitude; since every created good is by reason of a share in the divine goodness. Therefore things tend to a divine likeness by being causes of other things.

Again. That the effect tends to be like the agent, amounts to the same as that the agent causes its likeness in its effect: for the effect tends to the end towards which it is directed—by the agent. Now the agent tends to assimilate the patient to itself, not only in respect of its being, but also in respect of its causality: because the agent gives toits natural effect not only those natural principles whereby it subsists, but also those whereby it is a cause of other things; thus the animal, when begotten, receives from its begetter both the power of self-nourishment, and the power of generation. Therefore the effect tends to be like the agent, not only in the point of species, but also in the point of its causality of other things. Now things tend to be like God, even as effects tend to be like the agent, as proved above.’ Therefore things have a natural tendency towards a divine likeness in this, that they are causes of other things.

Moreover. A thing is most perfect when it is able to produce its like: for that light shines perfectly, which gives light to others. Now whatever tends to its own perfection, tends to a divine likeness. Wherefore a thing tends to a divine likeness from the very fact that it tends to be the cause of other things.

Since however a cause, as such, is higher than its effect, it is evident that to tend in this way to a divine likeness, so as to be a cause of other things, belongs to the highest grade among things.

Furthermore. A thing is perfect in itself before being able to cause another, as we have stated already. Hence to be the cause of other things is a perfection that accrues to a thing last. Since then the creature tends to a divine likeness in many points,” this remains last, that it seek a likeness to God by being a cause of others. Wherefore Dionysius says (Cel. Hier. iii.) that it is of all things most godlike to be God’s co-operator; in which sense the Apostle says (1 Cor. iii. 9): We ave God’s coadjutors.