from The Christian Philosophy of St. Augustine by Etienne Gilson
Chapter II: Matter and Forms
Now, we know that God produced and formed everything simultaneously, but we see that the new beings continually appear. How are we to resolve this apparent contradiction? To get out of the difficulty, St. Augustine distinguishes two types of creatures, namely those fixed in their form in the work of the six days, and those which were created only in germ, so to speak and had to develop. The following which were in finished form from the moment of creation: the angels, who were the work of the first day, day itself, the firmament, earth, sea, air and fire, i.e. the four elements, stars, and finally man’s soul, which was created, as we see, before it was placed in the body. Only preformed at the time of creation were the primordial seeds of all living things to come, whether animal or vegetable, including Adam’s body which, through its union with a soul already in finished form, was to constitute the first man.
When Augustine speaks of the kind of existence those creatures have which were only preformed at the time of creation, he says that they were made “invisibly, potentially, causally, as future things which have not been made are made” (invisibiliter, potentialiter, causaliter, quomodo fiunt future non facta). The technical phrases he uses to designate this kind of existence are rationes causales or rationes seminales, which are usually translated “seminal reasons.” Because of these hidden seeds which contain everything future ages are to see unfolded, the world created by God may be said to be pregnant with causes of beings still to come. In one sense, then, the world was created complete and perfect, since none of the things seen in it escaped the creative act; but in another sense the universe was only created in an unfinished state, because everything that was to appear in it later was created only in germ or seminal reason. How may we describe these seminal reasons.
As to their nature, the seeds or seminal reasons are essentially humid, i.e. they belong to the element, water, one of the four created by God at the beginning. But in addition to this nature, seminal reasons possess a principle of activity and development that is the cause of their fruitfulness. In keeping with his Platonic metaphysics, which Scripture confirms, Augustine looks upon them as numbers which bring with them for development in time the efficacious forces contained in the works God finished before He rested on the seventh day. From this point of view, creation was complete from the beginning in this production of things “wherein all things were made together” (ubi facta sunt omnia simul), because all the forces which were to show their effects later were already contained in the elements, and the numbers, which are the vehicles of these primitive forces in time, add nothing to the sum-total of being produced by creation. It is true to say, then, as Scripture states, that God rested on the seventh day (Gen. 2, 2) because by then everything had been produced in germ, in moist seeds endowed with efficacious numbers; but it is equally true to say that God is constantly at work (John 5, 17), for even though He creates no longer, He keeps all things in being by His power, rules them by His wisdom and causes the seeds He created to reach the full development He prescribed for them.
When the Augustinian doctrine of seminal reasons is looked at from this point of view, it plays a role quite different from that sometimes assigned to it. Far from being called upon to explain the appearance of something new, as would be the case with creative evolution, they serve to prove that whatever appears to be new is really not so, and that in spite of appearances, it is still true to say that God “created all things simultaneously” (creavit omnia simul). That is the reason why seminal reasons, instead of leading to a transformist hypothesis, are constantly called upon by Augustine to account for the stability of species. The elements from which the seminal reasons are made to have their own nature and efficacy, and this is the reason why a grain of wheat produces wheat rather than beans, or a man begets a man and not an animal of another species. The seminal reasons are principles of stability rather than of change.