First Way, Part IV: The Cascades

Previous episodes in this exciting series, now drawing toward its thrilling climax:

• Background lays out the history of the Argument from Motion and the impatience of those who demand that it prove more than it asserts to prove (e.g., that it prove that Jesus is Lord or some such thing, as if the objector were genuinely concerned about this shortfall).
• Part I A Moving Tale discusses the concept of "motion" used in the Argument from Motion, and how this is persistently misunderstood today. 
• Part II Two Lemmas demonstrate that 

1. Whatever is being actualized right now is being actualized by another. 
2. There cannot be an infinite regress of instrumental changers,

• Part III: The Big Kahuna combined the two Lemmas into the first theorem and its corollaries

A number of objections and misunderstandings were also addressed in these prior posts.

We are now ready for Thomas' throwaway teaser: "and this [the unmoved mover] is what all men call God." Folks who have never read any further (if they have even read that far) are often puzzled. How do you get God out of that? TOF hears them cry in bewilderment.

The answer lies in the several hundred further Questions and Articles in which these points are developed. In the interests of brevity, a few subsequent proofs will now be stated without extensive arguments, but ought to be intelligible in the light of what has already been said.

Backstory

 Theorem 1. A first, unchanged changer must exist

1. Some things in the world are changing. (Observation)
2. Whatever is changing is being changed by another. (Lemma 1)
3. There cannot be an infinite regress of instrumental changers. (Lemma 2)
4. Therefore, there must be a changer that is not itself being changed by another.

"First" in First Mover means ontologically first and not necessarily temporally first. This is because essentially-ordered series "drill down" in the present and do not necessarily go backward in time.

Once we get to this point a whole bunch of other stuff about First Mover just drops out like apples on a Newtonian hydra.

 Corollary 1.1. First Mover is itself unmoved.

1. Suppose it were moved. Then it would have a potential being actualized.
2. But potentials can be actualized only by something else. (Lemma 1)
3. In which case, there is something ontologically prior to the first mover, a contradiction (to Theorem 1)

First Mover can now be called Unmoved Mover, Unactualized Actualizer, Unchanged Changer, or other sobriquets, all of which are subject to some misunderstanding today due to a blurring of vocabulary. 

Corollary 1.2. First Mover is a Being of Pure Act.

1. At each level of being, the potential existence at a higher level is actualized by the existence of something actual at a deeper lever (e.g., the potential motion of the muscles is actualized by the actual motion of the nerves. the potential motion of the nerves is actualized by the actual motion of the motor neurons, and so on.) (Lemma 1)
2. If this proceeds in infinitum, there would be no first member of the series and none of the higher movers would be moving (actualized). (Lemma 2)
3. Therefore, the series must terminate in something whose existence does not need to be actualized by anything else; that is, by a Being of Pure Act (BPA)

Corollary 1.3 First Mover is perfect

1. To be perfected with respect to X is to be moved from potentially X to actually X  (def.)
2. First Mover is Pure Act.  (§1.2)
3. Therefore, First Mover has no imperfections.

And we are now ready to rock-and-roll.

The Cascades

Theorem 2. A Being of Pure Act (BPA) must be unique.

1. Suppose there were two such beings.
2. To be distinct, one must possess an attribute X the other lacks, such as being here rather than there. (by definition)
3. But the one that lacks the attribute is then in potency to X and cannot be a BPA, a contradiction. (§1.2)

Hence, from this point on we can say the BPA.

Corollary 2.1. The BPA is the first mover of all essentially ordered causal chains.

Because otherwise there would be two or more BPAs, duh?

Theorem 3. The BPA is unchanging

1. A thing is changeable insofar as it has potentials
2. The BPA has no potentials (§1.2)
3. Therefore, the BPA is unchanging (immutable)

Corollary 3.1  The BPA is eternal.

1. To come into being or pass out of being is a change.
2. The BPA is unchanging.  (§3)
3. Therefore, the BPA does not come into being or pass out of being

Corollary 3.2 The BPA is necessary, not contingent

1. Whatever cannot not exist is necessary rather than contingent.
2. The BPA exists (§1) and is unchanging (§3)
3. Therefore, the BPA cannot not exist
4. Therefore, the BPA is necessary (def. of necessary vs. contingent being)

Theorem 4. The BPA is immaterial.

1. Anything material is subject to change in various ways and therefore possesses potencies. (by definition)
2. A BPA cannot possess potencies (§1.2)
3. Therefore, the BPA cannot be made of matter. 
4. Therefore, the BPA is not a body.
   Corollary 4.1 The BPA is not subject to time (its existence is simultaneous).
   
   1. Time is the measure of change in changeable being,so if a thing is subject to time, then something can be gained or lost by that thing. (def.)
   2. But the BPA is unchanging (§3)
   3. Therefore, nothing can be gained or lost by that thing
   4. Therefore, the BPA’s entire existence is simultaneous

Theorem 5. The BPA is simple (not a  composite).

1. Material being has extension, and therefore parts (def)
2. Anything with parts has potentials
3. The BPA has no potentials (§1.2)
4. Therefore, the BPA is non-composite (i.e., simple)

Corollary 5.1. The BPA is identical with its own essence.

1. Any being in which are found two factors one of which is per se and the other per accidens, is not identical with its essence. For example, this man is male, white, middle-aged, and named R. Dawkins. But the essence of a man is that he is a rational mortal being. Therefore, this man is not identical with his essence, having maleness, whiteness, middle-agedness, and the name R. Dawkins accidental to him in addition to his essence. (def.)
2. The BPA is simple. (§5)
3. Therefore the BPA is not a compound of per se and per accidens. 
4. Therefore the BPA is identical with its essence.

Corollary 5.2. The BPA's essence is identical to its existence.

1. For anything whose essence is not existence, “what-it-is” (essence) is distinct from “that-it-is” (existence). For example: we grasp the essence of unicorns, but  unicorns do not exist. 
2. There is no distinction between elements in the BPA (§5)
3. Therefore, there is no distinction between the BPA's essence and whether it exists
4. Therefore, the BPA’s essence just is its existence

That is, the BPA is Existence Itself. "Existence exists" and cannot not exist (cf. §3.2) otherwise nothing else would exist (§1). If the BPA could talk, it would call itself I AM.

Theorem 6. The BPA is not a species in a genus.

1. If two things differ in an essential property,  then they are not members of the same species. (def)
2. If they do not differ in any properties, then they are not two distinct things. (def)
3. Therefore, two members of a species differ in their non-essential properties. For example: X is here, and Y is there, but spatial location is not an essential property.

1. The BPA is simple (non-composite) (§5)
2. Therefore, the BPA is not composed of both essential features and accidental (non-essential) features
3. Therefore, the BPA is not a member of a genus. 

Theorem 7. The BPA is not a genus predicated of a number of species.

1. The general (genus) is divided into specifics (species) by differences, since if they were not different they would all be the same. For example: dog is divided into Fido, Rover, Spot, etc.; canine is divided into dog, wolf, coyote, etc. Fido differs from Rover. Dog differs from Coyote.
2. But there cannot be a difference that does not share in existence, since non-being is not the specific difference of anything. For example: Fido and Rover cannot be different unless both have existence.
3. But no differences can be apprehended in existence itself. A thing either exists or it does not. Existence is either/or, not more-or-less.
4. The BPA is Existence Itself  (§5.2)
5. Therefore, the BPA cannot be a genus predicated of a number of species.

§5, §6, and §7 demonstrate why one cannot lump the BPA in with Zeus, Thor, Spaghetti Monsters, and the like, as if it were some particular thing among other things.

Theorem 8. The BPA is infinite (unlimited). 

Preliminary: what this infinitude is not.

• The BPA is not infinite in numerical quantity, since there can be only one BPA (§2). 
• The BPA is not infinite in dimensional quantity, since it is not a material body (§4).
• The BPA is not infinite in composition, since it is simple (§5).

1. These quantities naturally have limits. (An actual thing will have a finite count, size, etc.)
2. If these limits are removed, as by abstracting through mathematics, the resulting infinities are imperfections in the finitude they have by nature.
3. But First Mover is perfect.
4. Therefore, the BPA is not infinite in these senses, but rather naturally lacks limits in its power and goodness.

1. Form, considered in itself, is common to many; 
2. But when received in matter, the form is determined to one particular thing.
3. Therefore, form is made finite by matter, which is the principle of potency.
4. A thing is limited only by some potential that limits it
5. The BPA has no potentials (§1.2)
6. Therefore, the BPA is unlimited

Theorem 9. The BPA is all-good.

1. As the singular First Mover (§2), the BPA is the common source of all goods.
2. But a thing cannot give what it does not have, either formally or eminently.
3. Therefore, the BPA contains all goods eminently.  

Corollary 9.1. The BPA is infinitely good. (§9 + §8)

An evil is a defectus boni, a "lack or deficit of a good."  It is not a feature, but the absence of a feature.  Therefore, the BPA is not all-evil.
 
Theorem 10. The BPA is desirable.

1. A thing is good according to its desirableness. 
2. Everything seeks after (desires) its own perfection (of its nature).
3. The perfection and form of an effect consist in a certain likeness to the agent,
4. Hence the agent itself is desirable and has the nature of a good. 
5. Therefore, since the BPA is the first effective cause of all things, desirableness belongs to it.

Theorem 11. The BPA is all-powerful.

1. As the singular First Mover (§2), the BPA is the common source of all powers.
2. But a thing cannot give what it does not have, either formally or eminently.
3. Therefore, the BPA contains all powers,either formally or eminently. 

 Corollary 11.1. The BPA is infinitely powerful. (§11 + §8)

Corollary 11.2 Consequently, there is something in the BPA that is analogous to the power of intellect and will in humans. 
Corollary 11.3 Therefore, the BPA is a person.  From now on, we can say "He" (or "She" if you prefer, but "He" works better metaphorically.)
Corollary 11.4 To possess intellect is to know.  To be perfect is to lack any limitations on an attribute.  Therefore, He is all-knowing. 

There is more. For example, the intellect and will represent two processions, and hence each has a subject and object. The subject (A) is the same for both processions, since the intellect and will are possessed by the same being.

The object of the intellect (B) is a conception and is expressed as words. The object of the will (C) is a desire for the product of the intellect and is expressed as love. The BPA knows himself and in knowing himself as infinitely good desires himself. We call A the Father, B the Word, and C the Spirit. Both proceed from the Father, but in the language of the intellect, we say the Word is "conceived" by the Father.

So First Mover leads us to a unique, infinite, immaterial, eternal, and necessary Being, all-powerful, all-knowing, and all-good, the source of existence for all material beings (i.e., the Creator), and himself a rational being and therefore (being pure act) possessing a triune nature.

At this point, one simply has to throw hands in the air and say what the heck are we talking about if we are not talking about that which we call God?

Indicium Librorum 

Aristotle. The Physics, Book VI. Book VIII
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Chastek, James. "Two bases for “everything in motion is moved by another," (Just Thomism, Jan 2, 2014)
Chastek, James. "Omne quod movetur as a principle of all physics," (Just Thomism, Jan 27, 2014 )
Chastek, James. "Inertia, the life of the inanimate" (Just Thomism, June 10, 2014)
Cohoe, Caleb. "There Must Be A First: Why Thomas Aquinas Rejects Infinite, Essentially Ordered, Causal Series," British Journal for the History of Philosophy, September 5, 2013
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Feser, Edward. "The medieval principle of motion and the modern principle of inertia" in Proceedings of the Society for Medieval Logic and Metaphysics, Vol.10, 2012.
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Martin, Edward N. "Infinite Causal Regress and the Secunda Via in the Thought of Thomas Aquinas"
Oderberg, David S. "‘Whatever is Changing is Being Changed by Something Else’: A Reappraisal of Premise One of the First Way," in J. Cottingham and P. Hacker (eds) Mind, Method and Morality: Essays in Honour of Anthony Kenny (Oxford: Oxford University Press, 2010): 140-64.
Pruss, Alexander. Aristotelian Forms and Laws of Nature.
Thomas Aquinas. Summa contra gentiles, I.13, (Dominican House of Studies) Thomas Aquinas. Summa theologica, I Q2 art.3, (Dominican House of Studies)
Thomas Aquinas. Compendium theologiae, Bk.1 ch.3, (Dominican House of Studies)
Unknown.  Compendium of Theology -- translated into modern English