Motion is Existed Before Creation
Some things can exist apart and some cannot. Substances can exist apart.
Therefore all things have the same causes, because, without substances, modifications and movements do not exist. Further, these causes will probably be soul and body, or reason and desire and body.
Analogically identical things are principles, i.e. actuality and potency; but these also are not only different for different things but also apply in different ways to them.
For in some cases the same thing exists at one time actually and at another potentially, e.g. wine or flesh or man does so. (And these too fall under the above-named causes. For the form exists actually, if it can exist apart, and so does the complex of form and matter, and the privation, e.g. darkness or disease; but the matter exists potentially; for this is that which can become qualified either by the form or by the privation.) But the distinction of actuality and potentiality applies in another way to cases where the matter of cause and of effect is not the same, in some of which cases the form is not the same but different; e.g. the cause of man is (1) the elements in man (viz. fire and earth as matter, and the peculiar form), and further (2) something else outside, i.e. the father, and (3) besides these the sun and its oblique course, which are neither matter nor form nor privation of man nor of the same species with him, but moving causes.
“Further, one must observe that some causes can be expressed in universal terms, and some cannot. The proximate principles of all things are the ’this’ which is proximate in actuality, and another which is proximate in potentiality. The universal causes, then, of which we spoke do not exist. For it is the individual that is the originative principle of the individuals. For while man is the originative principle of man universally, there is no universal man, but Peleus is the originative principle of Achilles, and your father of you, and this particular b of this particular ba, though b in general is the originative principle of ba taken without qualification.
“Further, if the causes of substances are the causes of all things, yet different things have different causes and elements, as was said; the causes of things that are not in the same class, e.g. of colours and sounds, of substances and quantities, are different except in an analogical sense; and those of things in the same species are different, not in species, but in the sense that the causes of different individuals are different, your matter and form and moving cause being different from mine, while in their universal definition they are the same. And if we inquire what are the principles or elements of substances and relations and qualities-whether they are the same or different-clearly when the names of the causes are used in several senses the causes of each are the same, but when the senses are distinguished the causes are not the same but different, except that in the following senses the causes of all are the same. They are (1) the same or analogous in this sense, that matter, form, privation, and the moving cause are common to all things; and (2) the causes of substances may be treated as causes of all things in this sense, that when substances are removed all things are removed; further, (3) that which is first in respect of complete reality is the cause of all things. But in another sense there are different first causes, viz. all the contraries which are neither generic nor ambiguous terms; and, further, the matters of different things are different. We have stated, then, what are the principles of sensible things and how many they are, and in what sense they are the same and in what sense different.
“Since there were three kinds of substance, two of them physical and one unmovable, regarding the latter we must assert that it is necessary that there should be an eternal unmovable substance. For substances are the first of existing things, and if they are all destructible, all things are destructible. But it is impossible that movement should either have come into being or cease to be (for it must always have existed), or that time should. For there could not be a before and an after if time did not exist. Movement also is continuous, then, in the sense in which time is; for time is either the same thing as movement or an attribute of movement. And there is no continuous movement except movement in place, and of this only that which is circular is continuous.
“But if there is something which is capable of moving things or acting on them, but is not actually doing so, there will not necessarily be movement; for that which has a potency need not exercise it. Nothing, then, is gained even if we suppose eternal substances, as the believers in the Forms do, unless there is to be in them some principle which can cause change; nay, even this is not enough, nor is another substance besides the Forms enough; for if it is not to act, there will be no movement. Further even if it acts, this will not be enough, if its essence is potency; for there will not be eternal movement, since that which is potentially may possibly not be. There must, then, be such a principle, whose very essence is actuality. Further, then, these substances must be without matter; for they must be eternal, if anything is eternal. Therefore they must be actuality.
Philosophers think that everything that acts is able to act, but that not everything that is able to act acts. To them, this means that the potentiality comes before actuality.
But if this is so, nothing that exists needs to exist; for it is possible for all things to be capable of existing but not yet to exist.
The theologians generate the world from night. The natural philosophers say that ‘all things were together’. These result in the same impossibility. How will there be movement, if there is no actual cause?
Wood will surely not move itself-the carpenter’s art must act on it; nor will the menstrual blood nor the earth set themselves in motion, but the seeds must act on the earth and the semen on the menstrual blood.
This is why Leucippus and Plato suppose eternal actuality. They say there is always movement.
But why and what this movement is they do say, nor, if the world moves in this way or that, do they tell us the cause of its doing so.
Nothing is moved at random. There must always be something present to move it. A thing moves in one way by nature, and in another by force or through the influence of reason or something else.
What sort of movement is primary? This makes a vast difference.
But for Plato, it is not permissible to name here that which he sometimes supposes to be the source of movement-that which moves itself; He says that the soul is later and equal with the heavens.
To suppose potency prior to actuality, then, is in a sense right, and in a sense not; and we have specified these senses.
Anaxagoras says that actuality comes before potentiality because reason to him is actuality.
Empedocles says this too in his doctrine of love and strife. Leucippus says that there is always movement.
Therefore chaos or night did not exist for an infinite time. Instead, the same things have always existed either passing through a cycle of changes or obeying some other law, since actuality is prior to potency.
If there is a constant cycle then something must always remain, acting in the same way. If there is creation and destruction, there must be something else which is always acting in different ways.
This must act in one way in virtue of itself, and in another in virtue of something else-either of a third agent, therefore, or of the first.
Now it must be in virtue of the first. For otherwise this again causes the motion both of the second agent and of the third.
Therefore it is better to say ’the first’. For it was the cause of eternal uniformity; and something else is the cause of variety, and evidently both together are the cause of eternal variety.
This, accordingly, is the character which the motions actually exhibit. What need then is there to seek for other principles?