Thomistic Apologetics

God's Existence

 

First Way: ST I, Q. 2, A. 3, Co.

​

It is certain, and evident to our senses, that in the world some things are in motion. Now whatever is in motion is put in motion by another, for nothing can be in motion except it is in potentiality to that towards which it is in motion; whereas a thing moves inasmuch as it is in act. For motion is nothing else than the reduction of something from potentiality to actuality. But nothing can be reduced from potentiality to actuality, except by something in a state of actuality. Thus that which is actually hot, as fire, makes wood, which is potentially hot, to be actually hot, and thereby moves and changes it. Now it is not possible that the same thing should be at once in actuality and potentiality in the same respect, but only in different respects. For what is actually hot cannot simultaneously be potentially hot; but it is simultaneously potentially cold. It is therefore impossible that in the same respect and in the same way a thing should be both mover and moved, i.e. that it should move itself. Therefore, whatever is in motion must be put in motion by another. If that by which it is put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again. But this cannot go on to infinity, because then there would be no first mover, and, consequently, no other mover; seeing that subsequent movers move only inasmuch as they are put in motion by the first mover; as the staff moves only because it is put in motion by the hand. Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.

​

Contemporary Analysis

​

Motion, the reduction of something from potentiality to act, is no more than the transition of a thing from one state to the next. Act/actuality refers to the state in which something is at a given moment, while potentiality refers to any possible future state in which something can be. Transitions between possible states can occur by some intrinsic operation, as is the case with living things when considered as a whole, or some external agent, as is the case with elementary particles. Even the intrinsic operation of living things receive their power from their composites, elementary particles. Now, no thing can be the cause of its own state because that would imply that it both is and is not in that state simultaneously, which is impossible. Rather, what is simultaneous is the agent causing the state and the state of the things being acted on. This simultaneity of cause and caused, is motion per se, that is, causality in being. Motion per se rather than motion per accidens, which is the change in state of the attributes which inhere in a thing, regards the immediacy of causality in any particular moment, as if we were to freeze time. Motion per accidens would regard time. There may be intermediate per se causes between the First Cause and the object under consideration. However, without a First Cause, there would be no intermediate causes, and therefore we cannot have an infinite regress of causes. Since the First Cause determines intermediary causes, the First Cause is therefore the ultimate cause of the determination of all things, whether directly or indirectly. This First Cause we call God.

​

Third Way: ST I, Q. 2, A. 3, Co.

​

The third way is taken from possibility and necessity, and runs thus. We find in nature things that are possible to be and not to be, since they are found to be generated, and to corrupt, and consequently, they are possible to be and not to be. But it is impossible for these always to exist, for that which is possible not to be at some time is not. Therefore, if everything is possible not to be, then at one time there could have been nothing in existence. Now if this were true, even now there would be nothing in existence, because that which does not exist only begins to exist by something already existing. Therefore, if at one time nothing was in existence, it would have been impossible for anything to have begun to exist; and thus even now nothing would be in existence — which is absurd. Therefore, not all beings are merely possible, but there must exist something the existence of which is necessary. But every necessary thing either has its necessity caused by another, or not. Now it is impossible to go on to infinity in necessary things which have their necessity caused by another, as has been already proved in regard to efficient causes. Therefore we cannot but postulate the existence of some being having of itself its own necessity, and not receiving it from another, but rather causing in others their necessity. This all men speak of as God.

​

Contemporary Analysis

​

The axiom on which this argument hinges is the conjecture that things which are possible or contingent, that is, things that did not have to exist but do, at some time did not. And this axiom is evident by the very definition of what it means to be contingent. Now, if we were to suppose that elementary particles were eternal, it would still be evident from observation that they are mutable, or changing, passing from one state to the next. There nature, or essential collection of tendencies, would then be contingent on quantum fluctuations or something of the sort which would transition between states, not only in form, a nature-dependent state, but also per se, in being. But if all things were of such a nature, to be or not to be per se and or per accidens (the definitions of which we discussed in the preceding post), then it would be possible that there was a moment when nothing was in existence. If this were the case, it would still be the case that nothing is in existence. Without anything in existence, there would be nothing to cause the existence in anything else. Without anything necessary, and further, not only necessary, but immutable, there would be nothing contingent. For a requisite for contingency is that which the contingent thing is contingent on. Even in things which do not go out of existence, but are of a determinant form, form being a specificity of state, their existence is contingent on their form. For if they were not a specific kind of thing, they would not have existence as that thing which they are. Therefore, there can hypothetically be unchanging things that are still contingent in some aspect of their being. These are referred to as necessary things which have their necessity caused. Therefore, there must be something necessary and immutable which is not of a determinate form to cause the determination of the form in other things. This we call God.

​

Fourth Way: ST I, Q. 2, A. 3, Co.

​

The fourth way is taken from the gradation to be found in things. Among beings there are some more and some less good, true, noble and the like. But "more" and "less" are predicated of different things, according as they resemble in their different ways something which is the maximum, as a thing is said to be hotter according as it more nearly resembles that which is hottest; so that there is something which is truest, something best, something noblest and, consequently, something which is uttermost being; for those things that are greatest in truth are greatest in being, as it is written in Metaph. ii. Now the maximum in any genus is the cause of all in that genus; as fire, which is the maximum heat, is the cause of all hot things. Therefore there must also be something which is to all beings the cause of their being, goodness, and every other perfection; and this we call God.

​

Contemporary Analysis

​

All things within genus and species, genus being a general category of things and species categories within a genus, vary in the perfections of their natures, nature being the principle of action or behavior that leads to some ultimate telos, or end/goal. To the degree that a thing is perfect according to what is expected of its nature, is the degree to which it is called good, for it embraces what is productive or beneficial toward its telos. Within each species, what it means to be good, and therefore nearer to perfection, differs. But, in all species, we judge something to be good or deprived of some good according to what we perceive its telos to be. Regardless of what we perceive something’s end to be, it has some objective end. No thing could be good objectively or relatively if there were not such thing as Goodness independent of the object which we call good. In any thing under consideration, its goodness is derived from Absolute Goodness which is reduced and contained in the form of the object under consideration. Plainly, a thing cannot be good except that it resembles Goodness itself. Being or existence is convertible or identical with goodness or truth. Truth is being under the aspect of its relation to the mind and goodness is being under the aspect of desirability. These are virtually distinct, meaning, they are distinct only in the mind considered under different aspect, but this distinction is grounded in something real. For something to have existence or being, there must be something which is utmost Being, possessing the goodness in all things abstractly, pre-eminently, perfectly, infinitely, and in an excelling way. Remove such a thing and not only do we remove the goodness in all things, but consequently the being in all things. This superior Being or Maximum we call God.

​

​

​

Commentary by Matthew Shuler