bmiller wrote:

And also, to my dismay I forgot to with Merry Christmas to ficino.

So Merry Christmas ficino!




 

Merry (?) Boxing Day and Saint Stephen's Day, bmiller! 

More later on generation and Helen Lang's books etc. Cheers, f
 

Hi ficino,

Happy New Year (almost).

ficino wrote:

Your intro can be reworded, "If it sustains them in their form/matter combo, it causes their motion [through n intermediaries]." But doesn’t this assume what needs to be proved, i.e. that there is a sustaining cause? Your antecedent seems to beg the interlocutor to deny Existential Inertia, a denial that I’ve been contesting.

I quoted Aquinas and his reason asserting that the generating cause as the ultimate source of natural motion in the present.  "everything that is moved is moved by another." is in reference to motion in the present sense, isn't it?  So it is apparent here that Aquinas considers the generating cause (the cause of the form of the thing) to be operating in the "now" and is the answer to the question of what is presently moving the thing.  This is simply the Thomist position.  It does not beg any question but offers an explanation of why things remain in existence at all for any length of time.  It is the middle position between Parmenides and Heraclitus.    Why should things just persist anyway?

ficino wrote:

...things are only in motion as long as the generating cause is active” seems pretty clearly an error on A-T principles. We can go into this point more if you’d like.

I don't think this is controversial.  After all you have argued that only existing things can be in motion, so if the generating cause ceases to keep a thing in existence, per Aquinas, it follows that it is not moving.  Of course for Aquinas, the generating cause is God.
​

ficino wrote:

Here you are not directly discussing EI vs. DDC (Doctrine of Divine Conservation). May I ask, though, whether you identify generation and conservation in existence as the same operation?

When Aristotle discusses violent motion of an existing material object, he elaborates that the motion has a beginning, a middle and and end.  So an agent causes an object to move from a state of rest...propagating through all of it's parts until the entire mobile can be said to move as a whole (beginning), then as the mobile continues to be pushed (middle) and finally when the agent ceases to cause the motion (end).  I read this as the agent being responsible for not only the beginning of that violent motion, but also the continued motion until the agent ceases to act.  Why would one assume that the agent responsible for the beginning of the existence of an object immediately cease to responsible for the continued existence of that object?  What other principle would one have evidence of to keep a thing in existence?

ficino wrote:

I am not sure Aristotle’s treatment of the natural motion of simple bodies makes sense, quite frankly, when he wants to put the natural motion of simple bodies under the direct sway of the UM. Later ancient and medieval commentators argued a lot about how this is supposed to work. I haven't studied that tradition of commentary.

You'll have to elaborate on your sense that there was such controversy on natural science in the West in later ancient and medieval times.  I think the perception that Aristotle's ideas were *completely* wrong is a myth of the Enlightenment. 

His ideas were studied, criticized and refined over the course of centuries, but modern science still retains his basic framework.  Bodies move either violently (via collision) or naturally (via the 4 forces).  Things don't move themselves (or happen) for no reason.  Things that change, change in a certain way that is natural for them, and so forth.

Specific ideas, such as projectile motion, were studied and refined into the theory of impetus and finally inertia.

So it would be wrong to point out that Aristotle was wrong about projectile motion so therefore he was wrong about everything. 

ficino wrote:

Hello bmiller, happy pre-New Year’s Eve!

As to SCG I.13: since it’s part of an argument from for God’s existence, it would beg the question to introduce premises that presume the God of Thomism.  Thomas can’t legitimately beg the premise that “the generating cause s the ultimate source of natural motion in the present,” because at this stage of the argument, nothing about an ultimate source of natural motion in the present has been established, and it has not been established that the generating cause is identical with the cause of the simple bodies’ motion in the present. We can only say it gave them a form in the past. From “everything that is moved is moved by another” it does not follow that this “other” is identical with the generating cause. Sophroniscus was the generating cause of Socrates, but Sophroniscus is not moving every motion undertaken by Socrates after birth. Thomas needs to demonstrate that the same cause that generated a group of simple bodies, or heavy or light things, is the cause that is moving them after they are generated. But we get no argument for the latter inference. I already proposed reasons against it, so I won’t repeat them. It doesn’t matter what doctrines form part of Thomism as a system. Since SCG I.13 is a proof of God’s existence, its premises can’t exploit other Thomistic theses that are formulated with God’s nature assumed. Your statement, “Of course, for Aquinas the generating cause is God,” cannot be exploited in a proof for God.

It also seems to me that you conflate operations that Aquinas himself distinguishes. If x generates y, it does not follow from the meaning of “generates” that x conserves y in existence afterwards. A separate argument is needed to establish that some unitary x does both of these things to y.

As far as Aristotle’s physics being wrong – I can’t say how much of it is wrong, but the person who said that it is “completely wrong” was Helen S. Lang (1998), not me! heh heh

As to controversy among post-Aristotelian commentors, I was only talking about the generation of the simple bodies. My understanding is that this was a disputed point among subsequent commentators on Aristotle; I read that Philoponus modified Ari’s presentation, but I have not read Philoponus. David Furley in an influential article on self-movers in Aristotle wrote that Ari never did give a fully satisfactory account of the origin of the natural motion of the simple bodies (earth, air, fire and water).

What is my takeaway from all this? One, I consider the motion of the simple bodies a problem for the history of Ari and Aquinas’ thought. Two, as to the soundness of the First Way and the legitimacy of attempts to read into it a refutation of Existential Inertia – I would not try to pull the latter out of a claim that motion in the First Way includes generation. That attempt is, I think, a bridge too far.

Well, I shall keep poking around. Again, best for the new year, and thank you for discussing these matters. 

 The problem with denying that what is moved is moved by another is that it would seem to necessitate necessary and unimpeachable motion(s). The cause e.g. of something's moving through free space is and was the transfer and application of kinetic energy to the object, without which it would not be moving. It also determines the speed or velocity of the object's movement. The loss or transference of that kinetic energy causes the thing to stop or slow down. So too do the factors of the medium of motion determine its speed and velocity: alter the medium (from say free space to a place with gravity then having air or water, etc) and the consequent motion the object will make will all be different.

If there isn't something "other" to a thing's motion or at least local motion it becomes difficult to explain how anything could ever stop moving, if its motion really is strictly of itself: what could impede it and why?

Edit:Added: I would also add that Aristotle's physics is quite good. His inclusion of gravitas and the consideration of the medium of motion as essential factors in movement was and is a great leap forward into thinking about motion correctly. Moreover his insistence on the necessity of contrariety in nature to account for change of all kinds was and is also quite correct. We might balk at the four elements but Aristotle only included them because they were the most obvious sources of natural contrariety. Today we would talk about positive or negatively charged particles, e.g., to explain change: chemistry certainly does this in predicting how things will behave in various situations. Aristotle basically reduced change to the principles of the dry and the moist and the cold and the hot, the various combinations grounding difference and variety in the natural world and providing for weight and levity and thus distribution. We have our elementary particles in the atomic and subatomic order, the potential combinations of which ground difference and variety in the physical world.

Last edited by Timocrates (12/30/2017 10:17 pm)

@ficino,

Happy New Year.

ficino wrote:

As to SCG I.13: since it’s part of an argument from for God’s existence, it would beg the question to introduce premises that presume the God of Thomism.  Thomas can’t legitimately beg the premise that “the generating cause s the ultimate source of natural motion in the present,” because at this stage of the argument, nothing about an ultimate source of natural motion in the present has been established, and it has not been established that the generating cause is identical with the cause of the simple bodies’ motion in the present. 

This assumes he is arguing against your position of EI.  In fact, he is merely providing the reason that things cannot be said to ultimately be moving themselves.  If inanimate things moved themselves then they could stop and start.  They cannot, hence there must be another principle at work in natural motion.  This is an argument Aristotle uses in Physics I believe, but don't ask me where right now.

ficino wrote:

We can only say it gave them a form in the past. From “everything that is moved is moved by another” it does not follow that this “other” is identical with the generating cause. 

Both Aristotle and Aquinas conclude natural movement is due to the form of the object.  Simple bodies are drawn to the center, while animals move due to the soul as well as being drawn to the center.  If you want to argue that A&A thought things moved themselves after being generated then please provide some quotes.

ficino wrote:

Sophroniscus was the generating cause of Socrates, but Sophroniscus is not moving every motion undertaken by Socrates after birth. Thomas needs to demonstrate that the same cause that generated a group of simple bodies, or heavy or light things, is the cause that is moving them after they are generated. But we get no argument for the latter inference. 

But Sophroniscus was not the only "generating cause" of Socrates and certainly not the ultimate "generating cause".  A&A have no problems with intermediate causes, but since things don't move themselves (or generate themselves) and infinite regress is ruled out, there must be an Unmoved Mover/Uncaused Cause.

ficino wrote:

I already proposed reasons against it, so I won’t repeat them. It doesn’t matter what doctrines form part of Thomism as a system. Since SCG I.13 is a proof of God’s existence, its premises can’t exploit other Thomistic theses that are formulated with God’s nature assumed. Your statement, “Of course, for Aquinas the generating cause is God,” cannot be exploited in a proof for God.

Well, I assumed that you were merely questioning the idea that A&A did not equate the generating cause with the Unmoved Mover.
Now I see you want to defend the idea of existential inertia.  So I will wait for your explanation how inanimate objects move themselves and keep themselves in existence.

ficino wrote:

As far as Aristotle’s physics being wrong – I can’t say how much of it is wrong, but the person who said that it is “completely wrong” was Helen S. Lang (1998), not me! heh heh

But of course your statement doesn't add much to the discussion since there are no specifics.

ficino wrote:

As to controversy among post-Aristotelian commentors, I was only talking about the generation of the simple bodies. My understanding is that this was a disputed point among subsequent commentators on Aristotle; I read that Philoponus modified Ari’s presentation, but I have not read Philoponus. David Furley in an influential article on self-movers in Aristotle wrote that Ari never did give a fully satisfactory account of the origin of the natural motion of the simple bodies (earth, air, fire and water).

Right.  No specifics here either.

ficino wrote:

What is my takeaway from all this? One, I consider the motion of the simple bodies a problem for the history of Ari and Aquinas’ thought. Two, as to the soundness of the First Way and the legitimacy of attempts to read into it a refutation of Existential Inertia – I would not try to pull the latter out of a claim that motion in the First Way includes generation. That attempt is, I think, a bridge too far.

Well, regarding One, do you think simple bodies move themselves?  The common myth is that Newton's First Law means that inanimate objects move themselves, but Newton in his Principia denies this himself.  If you disagree with Newton, then please provide some examples of simple bodies starting to move by themselves and stopping by themselves.

Regarding Two.  You have not provided a theory of "Existential Inertia" nor attempted to defend it.  You make it sound that Aquinas was attempting to refute some theory that no one has even defined.  How could he be trying to refute some theory that no one has defined?

@ficino,

Happy 2018.

OK, so you're saying you don't know of anyone who actually argues for EI.  I kind of thought that was the case.  
Somehow, someway, some people just assume it's the default position without argument.