Monday, December 31, 2012

Aquinas versus Newton?


Does Newton’s law of inertia undermine Aquinas’s First Way?  The short answer is No.  I gave a longer answer at pp. 76-79 of Aquinas.  I give a much longer answer still in my paper “The Medieval Principle of Motion and the Modern Principle of Inertia,” which I presented last year at the American Catholic Philosophical Association meeting in St. Louis and which is now available online in Volume 10 of the Proceedings of the Society for Medieval Logic and Metaphysics.  Follow the link to read the paper, which is followed by a response from Michael Rota and my rejoinder to Mike.

Be sure to read also Gyula Klima's paper on causation, Mike's reply and Gyula's rejoinder, and the other papers in the ProceedingsAnd browse the SMLM archive while you're at it.  Lots of good stuff there.

45 comments:

Alan Aversa said...

Nice Christmas presents. Thanks

Have you read anything by Thomas J. McLaughlin? He's the master on this topic. See his PhD thesis The Aristotelian definition of motion and the principle of inertia, University of St. Thomas (Houston), and his article "Nature and Inertia" in The Review of Metaphysics, Vol. 62, No. 2 (Dec., 2008), pp. 251-284.

Alan Aversa said...

Oh I see you cite McLaughlin. excellent ☺

George R. said...

This question of motion is of more importance than most people realize. What is at stake is the very principle that effects require causes. Once that principle is obliterated (and, believe me, there are people working on it as we speak) you can just turn out the lights in the House of Intellect -- it’s over.

With that in mind, I really must ask Ed why he insists on referring to Newton’s First Law as a “principle.” It most definitely is not a principle, but is merely an observation. The distinction is huge: a principle comes first, an observation comes last. A principle is the cause, observations only deal with effects. In our case here, the principles are that which is required before there can be any motion, i.e. the mobile object and the mover. After that comes the motion itself. Last of all comes the observation of the motion, which reveals, among other things, that an object in motion stays is motion, etc. This is the reason why there can be no real conflict between Newton’s law and Aristotle’s principle of motion: observations are interpreted in the light of principles.

Therefore,

Observation: An object in motion remains in motion.

Why?

Principle: Because it is moved by another.

Conflict resolved.

Michael said...

Thanks for the post George R. I find your last couple lines enlightening.

Mike said...

It's funny; I wrote a thesis on this very topic, titled "The Thomistic Prima Via According to Fr. Reginald Garrigou-Lagrange." I made use of Fr. G.H. Joyce's very helpful points in his book Principles of Natural Theology (in turn relying on Fr. T. Rigby, S.J.) where he addresses this objection at length and replies using St. Thomas's principle about a multiplicity of agents being employed instrumentally by a principal cause: "Multitudo non reddit rationem unitatis."

I see that Dr. Feser's article cites the same Fr. Joyce. Great minds think alike, no? :)

Happy new year to all.

Vincent Torley said...

Hi Ed,

Happy New Year! I enjoyed reading your article, which I thought was very fair-minded and rigorously argued.

I'd like to query one point you made, though. You wrote on page 13:

"For the tendency of the mechanical picture of the world, of which Newtonian physics is a chief component, has been to try to reduce the other kinds of change to local motion."

I'd like to point out that Aristotle and Aquinas also regarded local motion as fundamental. I'd like to quote from Aquinas' Commentary on Aristotle's Physics Book VIII, Lecture 14 - Many reasons why local motion is the first motion
Paragraph 1088:

"1088. With respect to the first [point] he [Aristotle] gives two arguments, in regard to the first of which he proceeds thus:

First he proposes what he intends, and says that since there are three species of motion: one with respect to quantity and called “growth and decrease,” another with respect to passible quality and called “alteration,” and a third with respect to place and called “local motion,” the last one must be the first of all.

Secondly, he proves this on the ground that it is impossible for growth to be the first motion. For growth cannot take place unless an alteration precedes it, because that by which something is increased is somehow unlike and somehow like... But when it is added and causes increase it is necessarily like. Now the transition from unlike to like does not take place except through alteration. Therefore, it is necessary that before growth, there must occur alteration through which food is changed from one contrary disposition to the other.

Thirdly, he shows that before every alteration there is a previous local motion, for if something is altered, it is necessary that there be something causing alteration, that makes the potentially hot come to be actually hot. But if this cause of alteration were always in the same way near at an equal distance to the thing altered, then it would not make it any hotter now than previously. Therefore, it is plain that the mover in alteration does not remain the same distance from what is altered, but is at one time closer and at another time farther away — and this cannot happen without a change of place. If, therefore, motion must always exist, then local motion must always exist, since it is the first of all motions. And if one local motion is prior to all other local motions, then, necessarily, if the foregoing is true, this first motion must be eternal."

Aristotle writes: “Now of the three kinds of motion that there are-motion in respect of magnitude, motion in respect of affection, and motion in respect of place-it is this last, which we call locomotion, that must be primary.” (Physics VIII, Part 7.)

Aristotle isn't a reductionist, but he explains other kinds of motion in terms of local motion. Consequently if it were granted that local motion was not a real change, Aristotle's argument for a First Mover would collapse.

Aristotle is also quite explicit that local motion requires that the mover and the moved must be in immediate contact with one another. See Aquinas' Commentary on Aristotle's Physics Book VIII, Lecture 9, Paragraph 1044:

"This is especially evident in local motion, for it is necessary that from the first mover to the last thing moved, all must touch one another."

I would therefore agree with you when you conclude on page 12:

"...the only possible cause of inertial motion — again, at least if it is considered to involve real change — would seem to be a necessarily existing intelligent substance or substances, of the sort the earlier Aristotelian tradition thought moved celestial objects. (Unless it is simply God Himself causing it directly as Unmoved Mover.)"

kuartus said...

Professor Feser, excellent article on the principle of inertia and its relation to the principle of motion.

Slightly off topic:
When is your new article on Aquinas Fifth way coming out? I recall you saying that you were working on an article about the fifth way recently.

reighley said...

This quote certainly caught my attention:

"thus the arrow is moved by the archer as long as it retains the force wherewith it was shot by him."

In so far as Aquinas could be taken as referring to the arrows kinetic energy, without having recourse to the modern terminology or mathematical apparatus.

Why doesn't he solve the problem by saying (as Newton and Einstein were in effect saying) that the archer is the cause of this "force wherewith it was shot by him" and it is this retained "force" that continues to move the arrow?

Mr. X said...

Slightly OT, but...

Professor (and anybody else who knows):

I'm a long-time lurker here, and I've read and enjoyed both TLS and Aquinas. There is, however, one thing I don't quite understand about the whole mechanism vs. aristotelianism debate. You blamed the rise of the modern, atheistic worldview on the rise of mechanism in the 17th century. But it seems to me that, if you reduce all matter to inherently property-less particles, then to explain the fact that nature operates by certain laws you have to posit some kind of separate law-giver who is necessarily unaffected by these laws and ontologically prior to them – that is, you have to have (at least a deistic conception of) God. So what I’m asking is this: have I misunderstood you, and the rise of atheism was actually due to something else; was the Enlightenment simply mistaken in abandoning the idea of God; or is there some way I haven’t noticed of explaining natural laws without God? Thanks in advance for any answers.

Daniel Smith said...

To my simple mind there's no conflict between Aristotle and Newton when one views motion in light of act and potency.

Something actually at rest is potentially in motion and something actually in motion is potentially at rest.

Both require an actualizing agent to go from potential to actual.

Anonymous said...

Mr. X,

The modern conception of physical laws could either be descriptive or prescriptive. If it's the former then there is no reason to believe that such things are laws, especially given the fact that such ideas are propagated on a modernist metaphysic. In other words, Hume's skepticism about induction pretty much annihilates any atheistic appeal to physical laws as anything more than a collection of observations that we have no reason to believe will remain so in the future. If the latter, (i.e. physical laws are prescriptive) then that would require a Law-Giver, hence Theism/Deism.

So the atheist really has nothing to appeal to when it comes to physical law other than some pragmatic appeals to science, and we all know how easily refutable such pragmatic claims are.

Simply put atheism = intellectual bankruptcy all the way down.

BeingItself said...

Anon,

Joshua prayed to a god, and the sun and moon stopped in the sky.

And you claim the problem of induction is a problem for atheists?

With Yahweh monkeying with the works whenever he sees fit, it's the Christian theist with the real problem.

kuartus said...

BeingItself,

No, you are wrong. Miracles such as stopping the earth's rotation, which is not what the book of joshua is implying happened, pressupose order and regularity. Nothing can be considered a miracle if there is no uniformity to contrast it to. There is no problem of induction for the theist since uniformity would necessarily have to be the norm for miracles to even be recognized as such. You fail.

Eduardo said...

No problem BI, then the problem is with Theists who believe their god or gods are constantly changing thing in unpredictable ways and with atheists XD.

Was that an attempt to refute Anon's argument?

Another thing, let's say that what the Bible said that happened is literal and it did really happened: G*d stop the moon and the sun and .... it kept going on it's merry way with the same old rules... I mean even going literal your argument doesn't work either as a reffutal nor as a rebuttal... actually I have no freaking idea what you are trying to do.

So I guess you are saying that induction can only be distrusted if things act in ways akeen to a god tempering with the cosmos... but errr, of course critiques of induction as far as I have seen don't seen to include gods of any kind.

Anonymous said...

A note of lamentation:

Nowadays, whenever I see BI's name whilst scrolling down the post, my reflexive response is, "Oh great, looks like I'm in for an obnoxious combox embolism consisting of vacuous assertions afloat a stale mixture of ignorance and arrogant."

What a shame. This wasn't always the case. At least he spares us the combox cancer of, say, Papalinton.

BeingItself said...

"Nothing can be considered a miracle if there is no uniformity to contrast it to."

I agree.

"Was that an attempt to refute Anon's argument?"

No. I was simply showing that the problem of induction plagues us all. It is a problem for atheists, bible-believing theists, and believers in a philosopher's god.

"my reflexive response is"

Maybe you should try critical thinking instead.

Eduardo said...

Nope you have only stated that it is this way. Why you think the problem of induction plagues everybody?

Second I am pretty certain that the way you wrote you meant to say that atheists don't have any problem with that, don't play tricks you know well what you were going for.

Philosopher's God! Hahahaha

BI things wouldn't change much if heused critical thinking, maybe anon is so used to the way you think about thing that he has no longer any need to critically analyse your speech.

So as for the argument you are trying to make, one of your premises must necessarily force everybody to be under this epistemological problem. So your position obviously needs to defend that the induction problem is related to something common to all humans. So either is Human's characteristics or a overarching rule of the universe.

Yeah basically I will the argument for you... Unless you have already thought about it.

Eduardo said...

But I am betting you haven't.... u_u admit you just got mad at ex-materialist Anon because he made all those sweeping assertions!!!

Anonymous said...

Eduardo,

ex-materialist Anon

What was it that gave it away? ;-)

Anonymous said...

BI,

No. I was simply showing that the problem of induction plagues us all. It is a problem for atheists, bible-believing theists, and believers in a philosopher's god.

No, it doesn't plague us all. It's an epistemological problem created by an atheistic metaphysic and the rejection of Aristotelian causes.

Your claims about induction and Philosophical Theism/Deism are just ridiculous and appealing to miracles does not create a problem for Bible believing Christians.

Anonymous said...

By the way, the lamenting anon is a different one. The last two responses are mine as is the original diatribe against atheism/materialism and the problem of induction.

Eduardo said...

if only you people .... picked a name XD.

Anonymous said...

if only you people .... picked a name XD.

You still figured out that it was ex-materialist anon!

:-O

Eduardo said...

Sure, I read every post and then I add it to my spy database all your comments!

The main computer after that, looks for patterns and intentions, since people usually don't change their ways too much so it is easy MOST OF THE TIMES to know who is who XD.

Alright there is no computer I do it all myself.

BeingItself said...

Anon,

Anyone can fabricate a metaphysics to "solve" any philosophical problem.

I don't find such hand waving solutions satisfactory.

Anonymous said...

Anyone can fabricate a metaphysics to "solve" any philosophical problem.

Good, then go ahead and do so while...

Truly solving the problem.
Not introducing new problems.
Not just saying 'brute fact' and leaving it at that.
Having your solution be self-consistent.

Go for it.

I don't find such hand waving solutions satisfactory.

Because you don't understand them, or you wouldn't be calling them hand-waving.

What you don't find satisfactory are solutions that you feel uncomfortable with. Get over it.

Anonymous said...

Anyone can fabricate a metaphysics to "solve" any philosophical problem.

Allow me to correct you...

Anyone can fabricate a metaphysics to "create" unnecessary philosophical problems.

Your metaphysic does precisely that, hence the problem of induction.

rank sophist said...

Anyone can fabricate a metaphysics to "solve" any philosophical problem.

I don't find such hand waving solutions satisfactory.


And I don't find your question-begging assertions satisfactory. Not that I expect more from a mindless troll like yourself.

Eduardo said...

Oh wait.... We are back explaining things again!

BI, I bet what you really saying is that.... Only mechanical explanations are really explanations.
But aren't you inventing stuff on your own? You know, to conform with your metaphysical view of the world?

Obviously you don't believe in such hand waving procedure!

Anonymous said...

BeingItself said... Anyone can fabricate a metaphysics to "solve" any philosophical problem.

Yeah, coming up with ideas to explain things is called "figuring stuff out". (You should try it some time!)
When your ideas explain things around us it's called "understanding the world". (You should try it some time!)
If you get a good enough system going, it's called "a science". (You should -- ah, let's stop kidding ourselves.)

reighley said...

@Eduardo,
"Oh wait.... We are back explaining things again!"

Hooray!

seanrobsville said...

If you get a good enough system going, it's called "a science".

The physics-based sciences construct their models, predictions and explanations by abstracting and reducing the numerous natural instances of processes operating on structures, into a few generic procedures operating on data.

Hence physical explanations will be impossible to construct, will fail, or will be innapplicable as 'category errors' for any phenomena where

(i) Processes cannot be reduced to procedures
(ii) Structures cannot be reduced to data

I suspect that one of the intractable features of The Hard Problem is that some of the processes of consciousness are not even in principle reducible to procedures (they are 'non-algorithmic'). Similarly, qualia cannot be reduced to data. Consequently, attempts at physical explanations may be a category error.

The domain of science concerns those aspects of the world that can be modelled effectively and efficiently in terms of algorithms and data-structures.

'Effectively' means that the models have predictive power (and hence are falsifiable).

'Efficiently' means that the models are simpler and more general than the phenomena that they model (they embody 'algorithmic compression')

All non-algorithmic phenomena, by their very nature, are outside the scope of science.

Consequently, the 'materialists', 'physicalists', 'reductionists' and other practitioners of scientism are committed to trying to represent the three-dimensional world of causality, composition and mind, in terms of the two dimensions of algorithms and datastructures. This process ultimately requires them to insert various square pegs (qualia, semantics, intentionality, freewill etc) into the round hole of computationalism.

The lack of progress with The Hard Problem is one of the best illustrations of the failure of their project.

grodrigues said...

@BeingItself:

You are the living proof that having a brain, while necessary, is not sufficient for human, rational thought. Have you considered donating yours to science? And by donating, I mean donating it *now*. It is not like you have any use for it, besides filling the hollow void of your skull.

Anonymous said...

Sean,

That's a very interesting way of putting it. This following passage specifically is I think is a very accurate explication of the current state of affairs:


Consequently, the 'materialists', 'physicalists', 'reductionists' and other practitioners of scientism are committed to trying to represent the three-dimensional world of causality, composition and mind, in terms of the two dimensions of algorithms and datastructures. This process ultimately requires them to insert various square pegs (qualia, semantics, intentionality, freewill etc) into the round hole of computationalism.

The lack of progress with The Hard Problem is one of the best illustrations of the failure of their project.


Amka Gabriel said...

Speaking about philosophy ideas like Aquinas or Newton is never ending. I like it.

BenYachov said...

Prof Oerter is pissing me off big time!

http://somewhatabnormal.blogspot.com/2013/01/we-have-heard-on-high.html?showComment=1357576702377#c5515962622123240494

Eduardo said...

Amazing, it seems that Oerter is just going, and interpreting what he most likely feels is the correct interpretation istead of slowly reading the text and trying to see what the author is up to, what are the interpretations to what the author is saying...

But well... you now when you are a member of the Escarlate A corp (Neo-atheist sysmbol) you are not really expected to have any kind of rational thought!

So no surprise here, good thing my theory is going A-Okay.

יאיר רזק said...

Professor Feser - I have a question about the article which I hope you'll answer.

It seems to me your best defense of the compatibility of the two principles is when you argue that inertial motion can be seen as the modern-day natural motion. However, you never explain how natural motion is compatible with the motion principle (well, not with a detailed explanation I could chew on). Isn't the concept of natural motion precisely denying that motion always requires an external cause - that change always requires an external cause to actualize it?

The same could be said for the theory of impetus, BTW.

I would add that I found your defense lacking in that (a) I found the position that a change in position is not a change untenable, and (b) with inertia seen as real-change, the defense is to multiply entities and causal relations rather than to provide an Aristotelian metaphysical interpretation to the physical entities and relations.

Thanks for the article and your time,

Yair

P.S If anyone wants more details on my view, see
http://thebiganswers.wordpress.com/2013/01/08/principle-of-motion-versus-inertia/

Anonymous said...

If anyone wants more details on my view, see

No one wants to see the details of your nonsense. We've heard enough. You don't even understand the argument. Not to mention that your philosophical aptitude is deplorable and your obsession with scientism is not only self-refuting but laughable.

Stop embarrassing yourself.

Eduardo said...

This sort of a awkward procedure, why should you multiply entities instead of giving a metaphysical account.

What exactly guides this choice?

Anonymous said...

Eduardo,

Because he also wants to reject Ockham's razor it seems. There is no end to the irrationalism. Please make it stop.

BenYachov said...

Like I said Yair is treating the argument as a description of physics & not one of metaphysics or philosophy of science.

Indeed he dismisses the difference between philosophy of nature vs science as mere "word games".

His whole post is one big category mistake.

Maybe Feser will try to set him straight & or maybe he will be too busy in England to notice.

We shall see.

BenYachov said...

Let's deconstruct Yair here and now. I just finished watching RED DWARF X on DVD which came in the mail so I am feeling the smeg.

>It seems to me your best defense of the compatibility of the two principles is

First note in both the above statement & on Yair's blog he fails to acknowledge the category difference between the two principles. The Aristotelian Principle of Motion being one of metaphysics vs Inertia being one of physics.

>when you argue that inertial motion can be seen as the modern-day natural motion. However, you never explain how natural motion is compatible with the motion principle (well, not with a detailed explanation I could chew on).

At this point he want Feser to explain the APOM in terms of a theory of physics. Like asking Dawkins to explain the atomic weight of natural selection. Big time category mistake.

>Isn't the concept of natural motion precisely denying that motion always requires an external cause - that change always requires an external cause to actualize it?

The Feser's Paper clearly states it's not possible for natural motion to be explained in terms of an external conjoined physical mover.

Citing Aquinas interpreting Aristotle Feser writes QUOTE"[Aristotle] says, therefore, that what has been said is manifested by the fact that natural bodies are not borne upward and downward as though moved by some external agent.
By this is to be understood that he rejects an external mover which would move these bodies per se after they obtained their specific form. For light things are indeed moved upward, and heavy bodies downward, by the generator in as much as it gives them the form upon which such motion follows... However, some have claimed that after bodies of this kind have
received their form, they need to be moved per se by something extrinsic. It is this claim that the Philosopher rejects here.13

Additionally Feser cites Aquinas to say QUOTE"An instrument is understood to be moved by the principal agent so long as it retains the power communicated to it by the principal agent; thus the arrow is moved by the archer as long as it retains the force wherewith it was shot by him. Thus in heavy and light things that which is generated is moved by the generator as long as it retains the form transmitted thereby… And the mover and the thing moved must be together at the commencement of but not throughout the whole movement, as is evident in the case of projectiles.14

BenYachov said...

Yair moved by his Postivism & blind ad hoc insistence on treating this as a scientific description of physics writes QUOTE"Feser unfortunately does not explicitly explain how this notion of “natural motion” fits with Principle of Motion. He says only that “a body will of itself tend to move towards its natural place by virtue of its form” [emphasis added] –but the object’s form (it’s essence, or structure) isn’t “something else… that is already actual” [emphasis added], as Principle of Motion 2 requires."END QUOTE

Yes he did just say "a form is not actual as the Principle of Motion requires".

Aristotle's metaphysics teach form does actualize matter to become an object. But of course not all forms actualize matter like for example substantiate forms. Forms doesn't have to always be literally physical. Actually being "an object in Inertial motion" is it's form which was imparted when it was actualized as a moving object. It is actualized with the power to constantly increase it's distance from it's starting point
till acted upon.

He just doesn't get that.

>(a) I found the position that a change in position is not a change untenable,

Feser taking the explanations of many physicists at face value(like Lee smolin) describing inertia as a state merely shows how that is compatible with APOM. Yair thinks Feser is actually arguing Inertia as a state doesn't really involve change. Tedious!

>and (b) with inertia seen as real-change, the defense is to multiply entities and causal relations rather than to provide an Aristotelian metaphysical interpretation to the physical entities and relations.

That there is something external to our reality that causes things to have the natures they have & thus the powers they have is the point of metaphysics.

If he wants to give up realism & argue there is nothing outside of physical reality then fine make that philosophical argument but don't flaunt your ignorance claiming the APOM is not a metaphysical explanation.

I will let the professionals respond better.

Hopefully grodrigues or the O'Flynn will intervene maybe Sybellus or RS. They could explain it better than I with my poor skills.

Anonymous said...

Hi, Franz Wenger here,

No, surely it is not necessary to imagine that things are moved by some physical appendage of god pushing it along, like a child's toy.
But if each thing and event rises from the eternal and untouched being of deity, and that is god, then certainly god can be said to power the events, including the hurtling of a comet across the cosmos.
For the reasonable understanding posits a power to do what the universe does, god or no god.
And, if one has had a deep experience of the eternal unchanging peace that is untouched by creation, then it is patent that that power creates event after event and thing.
Those without such a deep and indubitable experience, cannot really understand how such a thing could be. To those who have had the experience, to whom the whole setup of things is as patent as their hand, no argument is necessary.
Without tasting a peach, any argument for what its taste is like--however clever--is moot.
According to a source present at the time, after a lengthy ecstasy toward the end of Aquinas' life, in response to an urging that he continue his writing, Aquinas said:
"I can do no more. Such secrets have been revealed to me that all I have written now appears to be of little value"
How could this be? The master of logic and theology denying the value of his great Summa---in the face of what?
I say he experienced directly the thing itself; he tasted the peach so to speak; he experienced the eternal within him (the kingdom of heaven is within)the eternal from which all arises.
And he felt that his beautifully constructed Summa was not the point, rather the experience he had had was the point.
And if his writing, as gloriously intellectual as it is and as grounded in religious intuition, could not enable this all important experience in others, then it was of 'little value".
Perhaps he had had the experience of being, as Eckhardt says, "raised entirely above creatures" including self, such that one does not know what one is,or where--there is no knowing at all, only isness is there ; the world drops away and what is left cannot be said to be and oneself cannot be said to be, and yet there is; this an account the intellect may subsequent to the experience produce.
Indeed, dialectic is far from such an experience exceeding and so paradoxical to the intellect.
The above is speculation but it has plausibility; Aquinas by all accounts was a devoted contemplative all his life, in addition to being a brilliant intellectual, and certainly valued revelation in the Summa.
It seems at the end of his life that direct experience proved to him that dialectic is at the periphery of the spiritual endeavour. The taste of the peach is the point and it births a true and indubitable understanding that the intellect and dialectic can only subsequently and inadequately reflect.
I think, with many others, incuding Aquinas apparently, that Philosophy and Theology are excellent stuff---but not the real thing.
Neither argument nor faith are necessary subsequent to indubitable experience of the eternal--which by its very nature
is impervious to doubt.
Or perhaps you could say it perfect faith given by the eternal.