TOF's DilemmaWe are now ready to prove two lemmas regarding motion, hence... dilemma. ROFL. Never mind. We interrupt this pun to stay on focus. Besides, there are a couple of initial propositions.
Those who have been following these maunderings would be well-advised to read
- Background and
- Part I
The opposite of divisible is a dimensionless point. Modern science regards the electron to be a point particle with a point charge and no spatial extent, but this is only true in a restricted sense. Our friend Figulus tells us than in real life, "confining an electron to an infinitesimally small space would require an infinitely large amount of energy. The electron's wave function is governed by Heisenberg's uncertainty principle, just like everything else in quantum mechanics, and so its wave function extends over space, which means it is not a point particle in the relevant sense."
Photons (which have no mass) are "like" electrons ("they are both screwy," said Feynman). But they are extended waves, not particles of absolutely zero size.
Proposition 1: Whatever is changing is divisible.
- If the whole is in potency with respect to X, then it is not changing with respect to X.
- If the whole is in act with respect to X, then again it is not changing with respect to X.
- Therefore, whatever is changing must be in potency and act.
- But it is impossible for a thing to be in potency with respect to X and in act with respect to X.
- Since the whole cannot be both, then a thing-that-is-changing must be changing in one part and not (yet) changing in another.
- Therefore, everything that changes must be divisible in parts. (Aristotle, The Physics, VI.4)
Proposition 2. All material things are divisible.
- Suppose a length is not divisible; then it is made up of a finite number of discrete indivisibles (i.e. dimensionless points)
- Either the points in such a series are separated or they are not.
If they are not separated, then they coincide in a single point, which has no length, a contradiction.
- If they are separated, there are distances between them.
- If there are distances between them, points can be marked in these distances; and so on as above to infinity.
- Therefore, the length is infinitely divisible.
|"The first man was Atom!"|
All material substances are divisible into molecules. These molecules are divisible into atoms. The atoms are divisible into protons, neutrons, and electrons. Protons are supposedly divisible into quarks. Quarks in turn are of distinct types: up, down, top, bottom, etc., differing by "color", "flavor", etc. and are therefore in principle also divisible. Even electrons seem to be divisible in Aristotle's sense, which surprised TOF no end.
Ready? Let's go.
Lemma 1. Whatever is changing is being changed by another.
- No divisible being can change itself as a whole. [Prop. 1]
- All material beings are divisible. [Prop. 2]
- Therefore, no material being can change itself as a whole.
When we recall that Aristotelian change is akin to acceleration, this is simply a restatement of Newton's first law. A body in equilibrium will remain in equilibrium unless disturbed by an outside force. And as we have seen in the previous Part, unchanged motion is simply another form of Aristotelian "rest."
- An atom emitting an alpha particle is being impacted by a neutron.
- A species that is adapting is being changed by natural selection (actually, by specific environmental conditions of one sort or another).
- A cat approaching a saucer of milk is being moved by its legs. That is, it is not moving "as a whole" but, being divisible, is being moved by its parts.
|As an apple reddens on the high bough;|
high atop the highest bough
the apple-pickers passed it by...
Sappho, Fragment 116
- Take an apple changing from green to red. At first it seems to be changing itself.
However, its color is being changed by sunlight in the 3,600 to 4,500 Å range. This light activates the anthocyanin in the apple's skin to absorb the near-ultraviolet, violet, blue and green regions of the spectrum, thus reflecting red.
|The redness of apples|
So sunlight changes the anthocyanin, which is a part of the apple-skin. In the common course of nature, red is that-toward-which the apple is determined. In a less common course, i.e., in the absence of light, yellow is the end of the process.
Corollary 1: The changer must be actual with respect to the potency being actualized.
- That which is merely in potency does not actually exist.
- Whatever does not actually exist cannot do diddly-squat.
- Therefore, that which reduces a thing's potency to actuality must itself be actual.
Now there are often objections made to this by folks who (glancing ahead toward the telos of the syllogisms) feel compelled to deny the freaking obvious.
Objection A: What about inertia, hunh?
Inertia is not a principle of motion, but a resistance to change in whatever motion the body already has. As such, it bears a striking similarity to the principle of life in living bodies. As such, inertia is the very reason why a change in motion requires an outside force! A body in inertial motion is not changing its motion. It is changing its location, and the cause of that change is whatever imparted the original momentum in the first place. [Feser, 2012]
The inertia concept does not seem to apply to other forms of motion: change of quantity or quality, as in generation/destruction, increase/diminution, and alteration. An apple moving from green to red does not keep going by inertia out into the infrared; a cat approaching a saucer of milk does not continue walking past it.
Objection B: What about quantum effects, hunh?
There ought to be a rule that says the first person to invoke quantum mechanics loses the debate.
This objection often takes the form of a claim that radioactive decay is uncaused. But what is really meant is that an individual decay event is unpredictable. But the same is true in thermodynamics and life insurance: we lack information on all the individual elements and so we must content ourselves with statistical pattern predictions rather than predictions of actual individual units. (cf. von Hayek, "The Pretence of Knowledge.") But even if an individual death event is typically unpredictable, no one claims that there is not a cause of death!
Newtonian mechanics cannot predict
which apple will fall or when.
Are falling apples uncaused?
In fact, radioactive emissions do seem to have causes. If they did not, we would be unable to create them at will in nuclear piles. Bombardment with neutrons seems to work quite well.
The cause of the decay of an atom, says Figulus, is quantum mechanical tunneling, and it is governed by the time evolution of the atom's wave function. Over time the undecayed atom evolves into a superposition of decayed and undecayed states. According to the Copenhagen interpretation, the decay (or non-decay) of the atom is then caused by an observer looking at it. There are, of course, other interpretations beside Copenhagen who can give different causes, but they all give causes.
Now just as we may be unable to determine a cause of death, we may be unable to determined the cause of any one particular radioactive emission. (One supposes a multitude of potential causes available in either case.) But to claim that "we don't know what caused X" is not equivalent to "Nothing caused X."
We've only been noodling over the quanta for about a hundred years or so, so it's not beyond reason that we don't know everything yet. That quantum mechanics works out statistically means little. It's what von Hayek called the "pretence of knowledge." Besides, look how long Ptolemaic mathematics worked without being physically true! There is a nice little overview by Richard Hassing of the differences between Aristotelian, classical, and quantum physics here.
Objection C: You haven't shown that every change even requires a changer! Hunh?
This is a denial that motion even requires an explanation at all. It's not that X is moved by another, by itself, or whatever; it's that it is not moved by anything. This one causes jaws to drop. Motion JUST IS! It is inexplicable. That sound you hear is the entire Scientific Revolution crashing and burning.
If TOF were to add up all the items denied by people trying to dance nimbly around the forthcoming conclusions, they would add up to an incoherent mess of mutually contradictory denials. When Free Will is on the table, sometimes foolishly justified by quantum uncertainty, the denialists will argue the strict determinism of 18th century mechanics. When First Cause is on the table, they will deny causal determinism and deploy quantum uncertainty. It is the denial that matters, not any desire for a coherent worldview.
The funny part about this objection is that no examples of uncaused motion are ever put forward. Go figure.
Of course, the more wary may realize that somewhere in our future is precisely something that moves without being moved, so they might want to rethink this objection.
Now there are more potent and technical objections to this first Lemma, such as those raised by Anthony Kenny. "Kenny accuses Aquinas of numerous logical fallacies, equivocations, irrelevancies, and—perhaps the most memorable accusation—of tying his arguments ... to an outdated and discredited Aristotelian/medieval cosmology." But TOF refers all such questions to Dr. Oderberg, who has written an entire paper on just this Lemma. James Chastek nicely summarizes the matter:Now cometh Lemma the second, and to deal with that we must first address a distinction.
The “moved by another” claim does originally mean... “no whole can be in motion unless it has parts which are moving”. This is clearest in organic wholes: if a hand is going to move, then the muscles need to move the tendons, and the tendons the bones. But this is also true of the inorganic: if some whole stone x is flying through the air and you stop a part of it, then either the whole x will stop altogether, or a part of it will break off and you will no longer have the whole stone. Either way, the relevant whole you were considering stops moving. Considered in this way, the only way one could have something natural in motion without its being moved by another would be if nature were composed of Euclidean points, but this seems impossible both a priori and on the basis of experiment. Nothing in nature is infinitely small.
-- "Moved by another and self-motion in nature" (Oderberg link added)
Distinction: A sequence of changers can be ordered essentially or accidentally. These are called per se and per accidens sequences.
A sequence is ordered accidentally if each changer in the sequence possesses the power to change another regardless whether any prior changer is still acting. For example: a woman may possess the power to give birth regardless whether her mother is still alive. She possesses the power of birthing in and of her own self.
A sequence is ordered essentially if each changer in the sequence possesses the power to change another only if a preceding changer is acting concurrently upon it. For example, a clarinet does not have the power to play Mozart's Clarinet Concerto in A in and of itself. It will only play if Sharon Kam is playing upon it concurrently.¹ A mover like the clarinet is called an "instrumental" mover, happily so since the clarinet is literally an instrument! In a similar wise, TOF's very own clarinet will not make music by itself. Unfortunately, it does not seem to make music even when TOF is playing it, although he has summoned ducks in this fashion.²
1. Sharon Kam. Or Benny Goodman, or Mr. Acker Bilk, or et al. C'mon, work with TOF here.
2. TOF was a triple-threat man in concert band: he could wield clarinet, bass clarinet, and oboe with equal ineptitude. The oboe was especially effective for calling ducks.
However, let us consider another example: that of a golf drive. The golf ball will not change its motion and leap off spontaneously toward the green unless the club strikes it. Certainly, it is moving with the rotating Earth and all that irrelevant crap; but it will not change unless it is struck, and kinesis means more specifically change by actualizing a potential. Similarly, the club possesses no power to move the golf club in and of itself. If the golfer is not swinging the club, the club will not be moving the ball.¹ The club is being moved in turn by the arms and shoulders, which are being moved by the muscles, which are being moved by the nerves, which are being moved by the motor neurons in the brain, which are being moved by chemical reactions at the synapses, which are being moved in turn by the will of the golfer.²
And more to the point of an essentially ordered series, the club will cease swinging if in media res the golfer were caught up in the Rapture™. Similarly, if Sharon Kam were removed, the clarinet would stop playing. Kinesis ceases!³
Stipulated, the club would undoubtedly fly off somewhere because the swing, once started, has given it an impetus that will take time to dissipate to the contrary impetuses of friction or gravity. But it stops changing relative to the act of driving a golf ball, and anything subsequent is accidentally ordered.
Similarly, some echo of the music may linger or there may be some time delay in the propagation of the music to more distant seats in the gallery,where they may hear the music after it has ceased being produced. This is utterly irrelevant. The concurrency of the mover and the mobile takes place at the point where the potential is being actualized. People who raise "objections" like these are no doubt sincere, but they have no idea how anal they sound. They think TOF is discussing a general theory of the physics of motion!
What it comes down to is this: instrumental (secondary) movers can propagate a change, but cannot originate it. We are now ready for the second lemma.
1. is moving. Notice the present progressive tense, which captures the sense better than Latin or Greek.
2. Yeah, will. Deal with it.
3. Kinesis ceases. It rhymes! TOF is tempted to do the entire post in rap.
|The gear train cannot proceed without limit. Without a first|
gear actually turning, none of the subsequent gears will turn.
This First Gear all men call Motor.
- An instrumental changer cannot transmit a change unless a primary changer is acting concurrently upon it.
- An infinite regress has no primary changer.
- There cannot be an infinite regress of instrumental changers.
Update: added comments by Figulus in the comm box to the narrative above.
- Aristotle. The Physics, Book VI. Book VIII
- Augros, Michael. "A ‘Bigger’ Physics," The Institute for the Study of Nature, Jan. 28, 2009 (MIT)
- Chastek, James. "On Jerry Coyne’s claim to miss no subtleties in St. Thomas’s arguments," (Just Thomism, Sep 8, 2009)
- Chastek, James. "Moved by another and self-motion in nature," (Just Thomism, Dec 2, 2013)
- 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)
- Feser, Edward. "Clarke on the stock caricature of First Cause arguments," (Feser blog, Jul 12, 2014)
- 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.
- Gage, Lawrence. "Aristotle's Atoms" (Real Physics, Feb 6. 2006)
- Hassing, Richard F. "On Aristotelian, Classical and Quantum Physics." (Lecture, Thomas Aquinas College, Mar. 7, 2003/updated 6/18/08)
- von Hayek, Friedrich August. "The Pretence of Knowledge," Lecture to the memory of Alfred Nobel, December 11, 1974
- Oderberg, David S. "Instantaneous Change without Instants," in C. Paterson and M.S. Pugh (eds) Analytical Thomism: Traditions in Dialogue (Aldershot: Ashgate, 2006): 101-18.
- 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.
- Sachs, Joe. "Aristotle: Motion and its Place in Nature" (Internet Encyclopedia of Philosophy)
- Schlappa, J. et al., "Spin–orbital separation in the quasi-one-dimensional Mott insulator Sr2CuO3." Nature 485, pp. 82–85 (03 May 2012)
- 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)
- TOF. In Psearch of Psyche: Some Groundwork. (The TOF Spot, July 11, 2014)
- TOF. America's Next Top Model, (The TOF Spot, February 4, 2014)
- Unknown. Compendium of Theology -- translated into modern English
- Vieru, Tudor, "Electrons Are Not Indivisible Particles." (Softpedia, April 19th, 2012)
Thanks for the post. I have been eagerly awaiting it and will look forward to the next in the series.ReplyDelete
As with my questions on the previous post, my questions here are so that I can better understand the argument. They are not meant as an attempt to refute or undermine your presentation. My primary question is, what is the significance or reason for arguing Lemma 1 ("whatever is changing is being changed by another") in the context of the part-whole structure of material beings? That is, Lemma 1 as formulated is supported by a three-point syllogism that concludes that "no material being can change itself as a whole." On its face, that conclusion doesn't seem to mean the same thing as "whatever is changing is being changed by another." Now, I understand that if, "by another", we mean a part of the whole, then the two statements are equivalent (because it is not the cat as a whole, but its legs that move the cat as a whole toward the milk, and it is not the legs as a whole that move the legs, but the muscles and tendons, and so on, either down to the lowest level of matter or "upwards" toward the soul of the cat, or perhaps both--that is another question for another day). But "by another" isn't limited to the parts of the being that is changed, is it? Doesn't it also include a material being wholly seperate from the being that is changed (such as the photons changing the chemical structure of the apple's skin such that the skin's color changes or the basebal bat that makes contact with the baseball and thereby change's the baseball's trajectory)? So, what I am trying to understand is the importance of discussing change by distinguishing the part-whole nature of a material being as opposed to simply discussing the more general conclusion that a being's potency must be actualized by another.
Well, whatever is changing is composed of parts. Consider a stone that has been thrown. If we somehow grab hold of a part of it, two things might happen.Delete
a) the stone stops moving because the part stopped moving
b) the part breaks off and the remainder of the original stone continues to move; but in that case, the stone-as-a-whole is no longer moving.
The emphasis on part-whole comes about because clever stutes think that by pointing to a cat walking across the room or an atom of radium emitting a particle, they are pointing to things that are moving on their own tick. "Whatever is changing is being changed by another" is simply the traditional formulation of the proposition; but a study of the argument and the Aristotelian source material suffices to show that it is the part-whole that is involved.
Check out for example:
The electron is sometimes described as a "point particle", but this is only true in a restricted sense. In real life, confining an electron to an infinitessimally small space would require an infinitely large amount of energy. The electron's wave funtion is governed by Hiesenberg's uncertainty principle, just like everything else in quantum mechanics, and so its wave function extends over space, which means it is not a point particle in the relevant sense.ReplyDelete
The cause of the decay of an atom is quantum mechanical tunneling, and it is governed by the time evolution of the atom's wave function. Over time the undecayed atom evolves into a superposition of decayed and undecayed states. According to the Copenhagen Interpreter, the decay (or non-decay) of the atom is then caused by an observer looking at it.
There are, of course, other interpreters who are not Copenhagen Interpreters, who can give different causes, but they all give causes.
Thank you, Figulus, for that markedly clear explication! I will incorporate your remarks in an update to the post.Delete
Thanks for an excellent series of articles on Aristotle's argument from motion. A few points:
(1) Aristotle refers to locomotion (as opposed to qualitative and quantitative change) as the primary motion, in his Physics VIII, Book 7. It follows then that in Aristotle's view, whatever explains locomotion can explain all other forms of motion.
(2) Premise (1) of your argument for the proposition that whatever is changing is divisible states that if the whole is in potency with respect to X, then it is not changing with respect to X. I don't see why this follows. To be in potency does not mean to be unchanging.
(3) Premise (5) in your argument for the proposition that whatever is changing is divisible states that if a length is made up of a finite number of points separated by distances, then "points can be marked in these distances; and so on as above to infinity." This doesn't follow: the laws of physics might prevent intervals being subdivided beyond a certain limit. Some physicists appear to think that space itself is quantized, and that the Planck length represents the smallest possible length (see the Wikipedia articles on Planck length, Planck scale and Quantum spacetime).
(4) You state that a sequence is ordered essentially if each changer in the sequence possesses the power to change another only if a preceding changer is acting concurrently upon it. Since instantaneous transmission of an impulse over a distance is physically impossible (for then it would be traveling faster than the speed of light), this means that any essentially ordered series of physical changes can only be of length 2: a body Y and another body X which is in immediate contact with it.
(6) Contrary to appearances the gear train is not an essentially ordered series. If I interfere with the motion of the first gear (e.g. by making it suddenly speed up or slow down), it will take a small amount of time for this change to affect the motion of the last gear.
(7) In the example of the golf club, we need to consider it as a divisible entity. If we look at the part in contact with the ball, we can say that its capacity to accelerate the ball, once acquired (as a result of the impulse traveling rapidly down the length of the golf stick), does not require the concurrent existence of the golfer or the upper part of the golf stick: if these were to disappear at the very moment when the bottom of the golf club was hitting the ball, it would still accelerate off the tee. The same goes for Sharon Kam playing the clarinet: once the particles she exhales leave her mouth and travel down the length of the reed, her continued existence is no longer required for them to produce a note.
I mention these points merely in order to show that the argument from motion is very tricky.
if the whole is in potency with respect to X, then it is not changing with respect to XDelete
IIRC, to be in change means to be in some way in potency and also in act. If a body is entirely in potency, then it ain't goin nowhere.
Since instantaneous transmission of an impulse over a distance is physically impossible
Folks always seem to think that all this is a theory about the physics of motion. When a book is laid on a table, how long does it take the table to push against the book? When a piece of wood takes on the form of a pencil, how long does it take the form to make it a pencil? There is no such thing as "instantaneous." As Whitehead pointed out in his Principle of Relativity, events in physics always occur over some finite period. The proper language is "concurrent" and one thinks of "the change taking place," regardless how long it takes to propagate. If Tiger Woods or the upper half of his golf club were to disappear, some kind of motion would then take place, but one could not properly call it a golf-swing.
If we take this as physically real, we wind up with Parmenides and the Paradoxes of Zeno, no? Of course, no one says that a division is physically achievable.
1.61619926 × 10^(-35) meters is one thing; but 0.80809963 × 10^(-35) meters is another regardless whether one can measure it or not.
If I interfere with the motion of the first gear (e.g. by making it suddenly speed up or slow down), it will take a small amount of time for this change to affect the motion of the last gear.
So what? The gear train will stop changing, even if it takes a short while.
once the particles [Kam] exhales leave her mouth and travel down the length of the reed, her continued existence is no longer required for them to produce a note.
Though it would be for the clarinet to remain lifted and for the concerto to continue beyond that last squawk. There is nothing mysterious about momentum or inertia. The last lingering not is something that is not changing, in the sense originally proposed.
there is an alternative way of viewing change which makes no reference to future states
How can a thing be in potency without being in potency to something? How can it be actualized without being actualized to something toward which it is in potency? An acorn is in potency to become an oak tree, or perhaps pig food. Once the actualization commences, one way or the other, the acorn is headed for the oak tree (or toward the pig's gullet). It is not headed toward a petunia, a Chevy Impala, or no place at all.
I understand Darwinians make much of this, claiming that "evolution" is undirected, which they confuse with nonspecific; but that is simply a metaphysical choice that was made back in the day, part of a general denial of of the powers of nature. It is this acceptance of the Modernist notion of "dead" nature that must be powered from without that has led to so much confusion here at the end of the Modern Ages.
"When we recall that Aristotelian change is akin to acceleration, this is simply a restatement of Newton's first law."ReplyDelete
Brilliant, never put the two together before. "Whatever is moved is moved by another" is the principle metaphysically at play under the locomotion-specific first law.
Your clothes would look nice on my bedroom floor. Click here and Check me out i am getting naked here ;)ReplyDelete