Calling Thomistic Philosophers: Induction and a posteriori demonstration

[Blue_Horizon]

BlueHorizon:

You are describing a period (of time, perhaps) wherein a questioner’s dialectic is incomplete. No induction in the learned world proceeds without a dialectical plan to guide it. In all such cases, induction affords a proof of the propositions that are ultimately accepted by the mind. Only to the extent that an investigator is still engaged in such a dialectic preliminary to induction, are his conclusions provable but not yet proved. Your argument is a red herring.

God bless,
jd

JD what is this preceeding dialectic you speak of? Can you provide an example to ground the discussion?

 

[Blue_Horizon]

BlueHorizon:

Where did you read this stuff?

God bless,
jd

I am saying a variety of things above - can you quote what you’d like me to respond to perhaps.

 

[Blue_Horizon]

Blue:

For instance . . .?

God bless,
jd

JD can you be a little more explicit what your “for instance…” referring to?

 

[Linusthe2nd]

Linus I am not sure I have communicated my concern as your response seems unrelated… Let me try again.

Lets start with an example of local motion. Say, dropping a cricket-ball.
Are you able to show me a chain of efficient causes (that of course ends in an unmoved-mover) that does not involve at least one efficient cause not in local motion.

I maintain it is impossible. At least one of the “movers” in that chain must effect a motion that is not local (which also implies that agent must be an intelligent being).

In this way the existence of God, I believe, cannot be proven by arguments based purely on local motion (ie speed/acceleration) alone.

On another tack I find it interesting that Aristotle’s UnMoved Mover argument was apparantly based more on final causality while Aquina’s equivalent argument was based on efficient causality.

This, it appears, was because Aristotle was rather keen on the principle that all beings (except God) had an inherent “appetite” for their causes. Hence local motion was a very good examplar of this principle… This appetite can be seen at work when a rock is dropped. In this way Aristotle could say that the First Cause was in fact unmoved when causing effects…it was the inherent appetite in the lesser being that wholly caused motion. The First Cause was totally unmoved. (In the case of a stone dropping to earth this is in fact incorrect of course so far as local motion is concerned. The Earth actually lifts slightly to meet the falling stone.)

Aquinas, from my reading, had no problem with also using efficient causality in his arguments for proving the Unmoved Mover. Aquinas srongly maintains that efficient causes never enter into the movement they cause in the moved thing. The cause receives nothing from the effect. Something like a “catalyst” I suppose. I do not know how he proves that principle re efficient causes.

Well, let’s be fair. What you are really asking for is a complete course in Metaphysics in on or two easy posts. That of course is impossible. That is one of the problems with trying to explain Thomas’ Five ways. Thomas himself, in the S.T. and the S.C.G. is writing for his students, Masters and Doctorial candidates in Theology/Philosophy. And those students were already proficient at least in all that Thomas had previously written ( i.e. his commentary on Aristotle’s Metaphysics, Boethius, the Sentences of Peter Lombard, the Disputed Questions, etc. So the Five Ways at the beginning of the S.T. had been prepared for by prior studies and that material had already been mastered.

But I shall try. First, once again, the First way does not depend on the success of the argument based on local motion. ( why you insist on that I don’t understand). The First way is based on any observable change/motion. Once we agree that there is change/motion in the universe Thomas moves into the metaphysicl phase of the argument.

All creatures are composed of the principles of potency and act. In physical creatures this is expressed as matter and form, where form is act in respect to the potency inherent in all matter. This inherent potency may be potency to one or more forms ( acts ). So all motion/change is a movement from one state of act through the actualization of some potency present in the matter. In this change/movement the old form ( act ) receeds into the matter as potency ( perhaps to remerge at some future time like the resurrection of the body) and the new form ( act ) emerges from the potency of the matter.

Now this change can only take place through a cause which causes the new act to emerge for nothing can move itself into a new act. It must be moved by something which has that act already, at least virtually as in a power. Nothing can give itself a new act, otherwise it would be able to create itsef, which is incoherent. I did not create myself, you did not create yourself.

So there must be a First Cause which is not in potency to anything, It is pure Act, and therefore can and does cause all instrumental causes to move/change. Since, as Thomas proves in Part 1 of the S.T. and other places, all creatures are composed of act and potency, this First Cause, the Pure Act, does not exist in the line of creatures but is transcendent to them. Yet, it is able to act on the secondary causes because it is in constant " contact " with them by His substance ( this Thomas proves in other places and is Catholic Doctrine, for " In Him we live, move, and have our being.")

You might read this by Dr. Peter Kreeft and see if it helps.

peterkreeft.com/topics/first-cause.htm

Now if I have failed to help and you still don’t see the validity of the argument just remember that we are not bound to agree with any speculative argument, whether from philosophy, Theology, or science except in so far as they agree with Catholic Doctrine. That is what we hang onto, that is our life line.

Linus2nd

 

[Blue_Horizon]

Well, let’s be fair. What you are really asking for is a complete course in Metaphysics in on or two easy posts. That of course is impossible. That is one of the problems with trying to explain Thomas’ Five ways. Thomas himself, in the S.T. and the S.C.G. is writing for his students, Masters and Doctorial candidates in Theology/Philosophy. And those students were already proficient at least in all that Thomas had previously written ( i.e. his commentary on Aristotle’s Metaphysics, Boethius, the Sentences of Peter Lombard, the Disputed Questions, etc. So the Five Ways at the beginning of the S.T. had been prepared for by prior studies and that material had already been mastered.

But I shall try. First, once again, the First way does not depend on the success of the argument based on local motion. ( why you insist on that I don’t understand). The First way is based on any observable change/motion. Once we agree that there is change/motion in the universe Thomas moves into the metaphysicl phase of the argument.

All creatures are composed of the principles of potency and act. In physical creatures this is expressed as matter and form, where form is act in respect to the potency inherent in all matter. This inherent potency may be potency to one or more forms ( acts ). So all motion/change is a movement from one state of act through the actualization of some potency present in the matter. In this change/movement the old form ( act ) receeds into the matter as potency ( perhaps to remerge at some future time like the resurrection of the body) and the new form ( act ) emerges from the potency of the matter.

Now this change can only take place through a cause which causes the new act to emerge for nothing can move itself into a new act. It must be moved by something which has that act already, at least virtually as in a power. Nothing can give itself a new act, otherwise it would be able to create itsef, which is incoherent. I did not create myself, you did not create yourself.

So there must be a First Cause which is not in potency to anything, It is pure Act, and therefore can and does cause all instrumental causes to move/change. Since, as Thomas proves in Part 1 of the S.T. and other places, all creatures are composed of act and potency, this First Cause, the Pure Act, does not exist in the line of creatures but is transcendent to them. Yet, it is able to act on the secondary causes because it is in constant " contact " with them by His substance ( this Thomas proves in other places and is Catholic Doctrine, for " In Him we live, move, and have our being.")

You might read this by Dr. Peter Kreeft and see if it helps.

peterkreeft.com/topics/first-cause.htm

Now if I have failed to help and you still don’t see the validity of the argument just remember that we are not bound to agree with any speculative argument, whether from philosophy, Theology, or science except in so far as they agree with Catholic Doctrine. That is what we hang onto, that is our life line.

Linus2nd

Thanks for the generous response Linus. I do not disagree.
The small point I was making above was simply that the argument from motion always requires the enquirer to posit intermediary instrumental causes not in local motion (ie some other movement from potency to act) if the final effect is local motion.
Given I havent been able to explain this to you in three trys perhaps I am missing something!

 

[dav3203]

The small point I was making above was simply that the argument from motion always requires the enquirer to posit intermediary instrumental causes not in local motion (ie some other movement from potency to act) if the final effect is local motion.

This thread is very good! lots of good resources have been quoted here. (Especially by you, BH).

Just to reply to the (quoted) point you have been making here: I think it’s a perfectly good point, and it’s one that I think a Thomist/Aristotelian should agree with (indeed, it’s certainly one that any Christian should agree with, for Christians hold that angels are “unmoved movers” insofar as they are not undergoing material changes). There’s nothing in principle preventing an angel from being the source of locomotive changes in the world. In fact isn’t there a tradition that says that there is a guardian angel for every planet, or something like that?

However, Edward Feser (in his essay on inertia in the medieval symposium) makes a suggestion that could be read as a refutation of this idea. If locomotive change is inertial, then it is infinite (unless frustrated by an external force). But only a being with infinite power can be the cause of infinite motion. Thus, the series of changers of locomotive change must have as a primary changer some being not undergoing locomotive change that also possesses infinite power.

If that reasoning is correct, then even locomotive change must terminate in nothing other than God—for even if angels were causing locomotive change, they couldn’t be the primary causes of such change, because locomotive change is infinite, whereas angels only have finite power.

Edit: When I say Feser’s point is “a refutation of this idea”, I mean the idea that if you restrict the first way only to cases of local motion, you won’t arrive at God. This isn’t quite what you said in the quote above.

 

[Blue_Horizon]

I think it’s a perfectly good point, and it’s one that I think a Thomist/Aristotelian should agree with (indeed, it’s certainly one that any Christian should agree with, for Christians hold that angels are “unmoved movers” insofar as they are not undergoing material changes). There’s nothing in principle preventing an angel from being the source of locomotive changes in the world. In fact isn’t there a tradition that says that there is a guardian angel for every planet, or something like that?

Thanks Dav. Just one thing I am not so sure on re what you mention above. Even if we posit the place of angels (and rightly so methinks) in God’s grand kaleidoscopal, cosmological hierachy/plan (Rickaby calls this infinitesimal gradation of cooperating, hierachical natures “evolution in co-existence” as opposed to modern “evolution by succession”. Have a look at SCG 68) I do not think we could truly say angels are “unmoved movers” in Aquinas’s thinking. That would only be true for locomotive motion.
Perhaps that is exactly what you are saying. If so, yes, you have exactly twigged where I am going and what I was thinking. Angels would very aptlyl be held responsible for ministering of the force of gravity (and the other 3 fundamental forces) because many angels, as Aquinas baldly states, have a duty re things of Earth (all material reality) while others to things purely Empyrean (spiritual). The four fundamental forces, to me, are the new “Celestial Spheres” …the borderline between the simplest material form and spiritual substance/powers. At this interface there can be no further locomotive change. Human intuition is defied by the lack of mechanical analogies to explain what is happening. Perhaps the simplest material form (short of non-existing prime matter) is indeed “force” or particles without mass. A contradiction to modern minds, yet that is where the top sub-atomic Scientists are going. The Higgs field may be a material form one step simpler than a massless particle.

However, Edward Feser (in his essay on inertia in the medieval symposium) makes a suggestion that could be read as a refutation of this idea. If locomotive change is inertial, then it is infinite (unless frustrated by an external force). But only a being with infinite power can be the cause of infinite motion. Thus, the series of changers of locomotive change must have as a primary changer some being not undergoing locomotive change that also possesses infinite power.

If that reasoning is correct, then even locomotive change must terminate in nothing other than God—for even if angels were causing locomotive change, they couldn’t be the primary causes of such change, because locomotive change is infinite, whereas angels only have finite power.

Now that is very deep! I am not even sure I understand exactly what is being posited let alone am I able to respond. Let me mull over this one .

(Is Feser’s article available online anywhere. I have never heard of the chap but he is obviously very well regarded and still living - I am starting to see refernces to him pop up all over the place).

 

[dav3203]

Thanks Dav. Just one thing I am not so sure on re what you mention above. Even if we posit the place of angels (and rightly so methinks) in God’s grand kaleidoscopal, cosmological hierachy/plan (Rickaby calls this infinitesimal gradation of cooperating, hierachical natures “evolution in co-existence” as opposed to modern “evolution by succession”. Have a look at SCG 68) I do not think we could truly say angels are “unmoved movers” in Aquinas’s thinking. That would only be true for locomotive motion.
Perhaps that is exactly what you are saying. If so, yes, you have exactly twigged where I am going and what I was thinking.

Yes, that was my idea there. So the distinction that you (and I) are making, I take it, is a distinction between motion from potency to act on the one hand, and locomotive motion on the other, which is but a species of motion from potency to act. Your claim is (and has been the last few posts) that if we read Aquinas’ first way with reference to local motion alone, and without reference to motion from potency to act, we will not be able to arrive at God, because the conclusion of the first way is that there exists an unmoved mover, and if by ‘unmoved mover’ we only mean a being that is not undergoing local motion, well then, the unmoved mover so understood could be an angel just as well as God, because angels just as well as God are not undergoing local motion, and (it seems plausible to assume) perhaps the angel Gabriel could be the sole cause of local motion in the world, with God coming into the picture only to sustain Gabriel in existence. But in order to get from Gabriel to God, you have to invoke a different kind of motion, one that is not local motion. Hence, the first way fails to (necessarily) arrive at God—and this was your original claim.

Now, the argument that I cited from Edward Feser is intended to be a counterargument to your claim, and it works by rejecting that last “plausible assumption” that an angel (or any unmoved mover other than God) can be the sole cause of local motion in the world. If his argument works, then only a being with infinite powers (i.e. God) could be the cause of local motion in principle.

Now that is very deep! I am not even sure I understand exactly what is being posited let alone am I able to respond. Let me mull over this one .

(Is Feser’s article available online anywhere. I have never heard of the chap but he is obviously very well regarded and still living - I am starting to see refernces to him pop up all over the place).

My friend, it’s the article you posted earlier in this thread it is the first one I believe, the Proceedings of the Society of Medieval Logic and Metaphysics (PSMLM). Feser’s article and the argument therein is there; Michael Rota comes up with an objection in the subsequent response, but Feser refutes that objection in a follow-up.

While I’m at it, I might as well make some other comments/questions—this one to hicetnunc:

hicetnunc:

There is a methodical difference in St Thomas between a posteriori and induction, but not the kind of difference found in Enlightenment epistemology. MacIntyre for one has a lot to say on this.

I’d be interested to know where MacIntyre discusses this. Is it just his Three Rival Versions or in other places as well? And whereabouts in TRV?
Also, hicetnunc, you say that inductive reasoning is otherwise (for the intents and purposes of this thread) basically the same thing as a posteriori reasoning (as opposed to Humean-style inductive reasoning). Well, I am currently trying to get clear on what induction is according to Aquinas. Take the following form of reasoning:
(1) The Eiffel Tower is an effect.
(2) Every effect has a cause.
(3) (Therefore) The Eiffel Tower has a cause.
According to St Thomas Is this inductive reasoning? Or deductive reasoning? Whichever one it is, could you give an example of the other? (I.e. if you say it is inductive, then what is an example of deductive? and vice versa).

 

[Blue_Horizon]

Now, the argument that I cited from Edward Feser is intended to be a counterargument to your claim, and it works by rejecting that last “plausible assumption” that an angel (or any unmoved mover other than God) can be the sole cause of local motion in the world. If his argument works, then only a being with infinite powers (i.e. God) could be the cause of local motion in principle. )

Gotcha. I believe the First Way (and indeed any alleged aposteriori proof of God’s existence by reason alone) has very little to say re the actual essence/definition of this “god.” Unlikely that this god’s essence is his existence (I was just listening to a Feser mp3 where he seems to be saying exactly this). I think we are quite entitled to call Gabriel a god, lesser powers in the history of religion have so why not?
There seems to be no aposteriori proof re anyone’s particular definition of “god”, from what I can make out, that goes beyond the usual generalities (eg unmoved mover). Maybe I am wrong on this point.

Not quite sure that an angel (or, why not, an “inanimate” spiritual “thing”) need be the sole cause of local motion. By this I mean we are only talking about instrumental causality.
Beings in local motion also have material and formal causes. Those causes may well derive from the creator god (unmoved mover of motions other than locomotive) without denying our angel as “unmoved mover” of local motion? )

My friend, it’s the article you posted earlier in this thread it is the first one I believe, the Proceedings of the Society of Medieval Logic and Metaphysics (PSMLM). Feser’s article and the argument therein is there; Michael Rota comes up with an objection in the subsequent response, but Feser refutes that objection in a follow-up.

Duuuhhhh .
Thanks. I tend to select articles based on the cogency of the arguments rather than the name of the author. (And there was I naiively picking holes in some of Feser’s comments in that article.) He seems to be very highly regarded so I better reread his article more closely.

Just a quick comment on your Eiffel Tower question…
Bsacially aren’t you asking how we know if Aristotles 4 causes principles are true?
If my observation is correct then it seems he is offering an explanation of all material changes we observe in nature. That suggests it can be no more than a hypothesis or a model. Consistant with “the facts” … but consistancy is not an absolute criteria of truth as many courtrooms discover years later when the criminal goes free cos there was another consistant explanation which happened to be the real one.
I find it interesting that the relationships of the defined 4 causes seems tautalogica (analytic). ie once you posit a cause (instrument) and an effect (terminus ad quo) then you must have a terminus a quo and consequently an underlying linking medium (material cause) and a principle that changes the being at terminal1 to what it becomes at terminal2 (form).

 

[hicetnunc]

I’d be interested to know where MacIntyre discusses this. Is it just his Three Rival Versions or in other places as well? And whereabouts in TRV?
Also, hicetnunc, you say that inductive reasoning is otherwise (for the intents and purposes of this thread) basically the same thing as a posteriori reasoning (as opposed to Humean-style inductive reasoning). Well, I am currently trying to get clear on what induction is according to Aquinas. Take the following form of reasoning:
(1) The Eiffel Tower is an effect.
(2) Every effect has a cause.
(3) (Therefore) The Eiffel Tower has a cause.
According to St Thomas Is this inductive reasoning? Or deductive reasoning? Whichever one it is, could you give an example of the other? (I.e. if you say it is inductive, then what is an example of deductive? and vice versa).

Hi Dav;

Thanks for raising those interesting points.

First off, the shift from Scholastic “epistemology” to Enlightenment epistemology is an ongoing concern for MacIntyre in just about all of his major works, including Three Rivals, Whose Justice, and After Virtue. He also discusses the “epistemological crisis” brought about by Enlightenment philosophy in his collection of essays, The Tasks of Philosophy (see in particular chapter 1; MacIntyre is of course not unique in pointing this shift out, simply someone who comes readily to mind: but there are many others who have tackled the problem of Enlightenment epistemology and its impact on modern culture. Someone else who comes to mind on this cultural shift is Charles Taylor.) What I find interesting about MacIntyre’s assessment is his linking of the epistemological shift with individualism, which he sees as leading to a breakdown in the ability to reason! Interesting stuff.

As for your Eiffel tower syllogism, I do not think that St Thomas would think of this as an inductive argument, first of all because syllogisms are, by nature, deductive demonstrations. But also, your first premise relies on an assumption derived from the second premise (Your second premise seems to be the first premise of a prior demonstration). Your first premise also seems to be either enthymematic (in which the justifying premises are suppressed) or a circular assumption. I’m not sure which…I’ll have a think on it some more. Inductive reasoning involves moving from a particular (sensible singular) to a universal and so forms the basis of the minor premise.

The key difference, I think, between Scholastic (and in particular, St Thomas’) understanding of the relationship between a posteriori and a priori reasoning is that the one leads to the other in the formulation of universal principles. A posteriori reasoning moves from effect to cause while a priori reasoning moves from cause to effect. The whole edifice of knowledge builds on a relationship between the two. This is why St Thomas’ so-called cosmological argument is often referred to as a metaphysical argument, even though it ostensibly relies on the inductive premise of contingent things in motion. But the demonstration moves from induction to deduction and I would say that, as a rule of thumb, this is the method of reasoning in general.

Hope that all makes sense…though I will give it some more thought…

 

[dav3203]

As for your Eiffel tower syllogism, I do not think that St Thomas would think of this as an inductive argument, first of all because syllogisms are, by nature, deductive demonstrations. But also, your first premise relies on an assumption derived from the second premise (Your second premise seems to be the first premise of a prior demonstration). Your first premise also seems to be either enthymematic (in which the justifying premises are suppressed) or a circular assumption. I’m not sure which…I’ll have a think on it some more. Inductive reasoning involves moving from a particular (sensible singular) to a universal and so forms the basis of the minor premise.

The key difference, I think, between Scholastic (and in particular, St Thomas’) understanding of the relationship between a posteriori and a priori reasoning is that the one leads to the other in the formulation of universal principles. A posteriori reasoning moves from effect to cause while a priori reasoning moves from cause to effect. The whole edifice of knowledge builds on a relationship between the two. This is why St Thomas’ so-called cosmological argument is often referred to as a metaphysical argument, even though it ostensibly relies on the inductive premise of contingent things in motion. But the demonstration moves from induction to deduction and I would say that, as a rule of thumb, this is the method of reasoning in general.

Interesting! So according to the scholastics, then, there is no such thing as an inductive syllogism, for all syllogisms are deductive in nature. The question, then, is: what form do inductive arguments take? From what has been said so far, it seems that they involve moving from the particular to the universal; however, they are also non-syllogistic processes of movement. But then what exactly are these processes? Are they inferences? Deliverances of the intellect? (If they are inferences, they seem to be syllogistic; but on the other hand, if they are simply deliverances of the intellect (i.e. deliverances analogous to the deliverances of the physical senses), then they don’t seem to involve ‘induction’ at all, but rather immediate apprehension with some necessary conditions attached: one could cash it out as immediate apprehension of a universal with the necessary condition that such an immediate apprehension be accompanied by sense experience of a particular instantiation of that universal).

So you could read my question as a friendly challenge to the scholastic claim that induction is a non-syllogistic ‘movement from particular to universal’. The challenge is that such a claim seems vague, and that attempts to clarify the nature of such a ‘movement’ (e.g. in terms of inference or immediate apprehension) will either fall back into syllogistic reasoning or else bear no resemblance to ‘movement’ in any real sense, which I assume is undesirable for an account of inductive reasoning.

Also, I’m afraid I don’t quite follow your points about the first two premises of the Eiffel Tower syllogism (although they seem very important). Feel free to construct what you think the hidden premises should be in such an argument.
BlueHorizon:

Bsacially aren’t you asking how we know if Aristotles 4 causes principles are true?
If my observation is correct then it seems he is offering an explanation of all material changes we observe in nature. That suggests it can be no more than a hypothesis or a model. Consistant with “the facts” … but consistancy is not an absolute criteria of truth as many courtrooms discover years later when the criminal goes free cos there was another consistant explanation which happened to be the real one.

I’m assuming that Aristotle’s reply would be that the principles are not hypotheses, but are self-evident truths. Hence, they are not simply explanations of phenomena that are on par with other rival explanations. Aristotle’s reply would be consistent with the idea that the syllogism is a deductive one. My question is not so much how we know that the first principles (such as ‘every effect has a cause’ etc.) are true; rather, my question is: what is inductive reasoning, and what form does it take? Perhaps the correct response (which Hicetnunc gave) is that we do arrive at the first principles by induction, because the first principles are universal in nature. But my questions in the above paragraph are intended to be follow-up questions to this kind of response. What exactly is the nature of the process by which one inductively arrives at universal principles from particulars, and why is it that such a process is induction as opposed to syllogistic reasoning or the direct apprehension of self-evident truth?

 

[Blue_Horizon]

Interesting! So according to the scholastics, then, there is no such thing as an inductive syllogism, for all syllogisms are deductive in nature. The question, then, is: what form do inductive arguments take? From what has been said so far, it seems that they involve moving from the particular to the universal; however, they are also non-syllogistic processes of movement. But then what exactly are these processes? Are they inferences? Deliverances of the intellect? (If they are inferences, they seem to be syllogistic; but on the other hand, if they are simply deliverances of the intellect (i.e. deliverances analogous to the deliverances of the physical senses), then they don’t seem to involve ‘induction’ at all, but rather immediate apprehension with some necessary conditions attached: one could cash it out as immediate apprehension of a universal with the necessary condition that such an immediate apprehension be accompanied by sense experience of a particular instantiation of that universal).

So you could read my question as a friendly challenge to the scholastic claim that induction is a non-syllogistic ‘movement from particular to universal’. The challenge is that such a claim seems vague, and that attempts to clarify the nature of such a ‘movement’ (e.g. in terms of inference or immediate apprehension) will either fall back into syllogistic reasoning or else bear no resemblance to ‘movement’ in any real sense, which I assume is undesirable for an account of inductive reasoning.

Also, I’m afraid I don’t quite follow your points about the first two premises of the Eiffel Tower syllogism (although they seem very important). Feel free to construct what you think the hidden premises should be in such an argument.

I’m assuming that Aristotle’s reply would be that the principles are not hypotheses, but are self-evident truths. Hence, they are not simply explanations of phenomena that are on par with other rival explanations. Aristotle’s reply would be consistent with the idea that the syllogism is a deductive one. My question is not so much how we know that the first principles (such as ‘every effect has a cause’ etc.) are true; rather, my question is: what is inductive reasoning, and what form does it take? Perhaps the correct response (which Hicetnunc gave) is that we do arrive at the first principles by induction, because the first principles are universal in nature. But my questions in the above paragraph are intended to be follow-up questions to this kind of response. What exactly is the nature of the process by which one inductively arrives at universal principles from particulars, and why is it that such a process is induction as opposed to syllogistic reasoning or the direct apprehension of self-evident truth?

Interesting thoughts.
I think it important not to confuse the sort of inductive thinking you are speaking of (which apprantly we may not call syllogistic for Aquinas), which is leaning towards, “immediate apprehension” with scholastic “abstraction” of a universal from sensible species.

While abstraction is always aposteriori (it starts with the particular, sensible world) I am not sure that is rightly called “inductive” thinking. At least not inductive in the post-enlightenment sense of the word.

By scholastic abstraction we arrive more at “essences” of substantial things rather than the sort of empirical “laws” or “principles” that modern induction arrives at.
I agree that both of these are a form of universalising thinking but I cannot quite put my finger on the difference in method.

Re Aristotle’s 4 causes being self-evident “synthetic” aposteriori empirical truths and not a hypothesis…not sure. They look like they are empirically self-evident but I suggest they could really be self-evident only because they are really “analytic” definitions.

To say that “all effects have a cause” is a self evident empirical truth seems a bit like saying all sons have fathers. To accept the given label/definition of the terms (rather than a neutral "dscription of the empirical reality) is already to smuggle in the relationship.

So if we rephrase the statement to “all phenomenon have a related preceeding phenomenon” then it does not look quite so self-evident anymore. Looks more like a hypothesis now.

So I suggest that a lot of “self-evident” aposteriori statements may not be really self-evident at all. “Self-evident” only seems to happen at the level of apriori “analytic” abstraction (triangles always have 3 sides) . If it seems to happen aposteriori it may be because of the way we define the empirical objects - which is often the way we sort of smuggle in the apriori analytic. Then it isn’t truly aposteriori.