[Serious] Thomism: Then & Now

[emjay]

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So does Aquinas use circular reasoning, as some suggest? I say no. There is a difference between motivated and circular reasoning. As a man of faith, Thomas Aquinas would most certainly be motivated to reason towards a conclusion. Motivated reasoning increases the likelihood of making mistakes but that does not mean the outcome must be wrong. In contract to this, circular reasoning is when the initial premise and the conclusion form a closed loop. This is not the case in the 5W.
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Firstly, in hindsight, I probably jumped the gun a little bit there, in my previous reply to you, thinking you had conceded it was circular reasoning, when that's not what you meant, so, sorry about that.

But since we're on the subject, I do still and have concerns on the subject, and so does my dad, who is following all of this with interest as well. Basically we both understand and accept the different concepts of an essentially ordered series and an accidentally ordered series, and that the former relies on a kind of simultaneous, as you put it elsewhere, "sustaining", causation. Aquinas' example being arm>moves>stick>moves>rock... where the simultaneous presence of each element is essential in order for the whole series to remain valid. Compared with an accidentally ordered series such as grandfather>begets>father>begets>son, where once the grandfather has begotten the father, the father can beget the son regardless of whether the grandfather is alive or dead (ie currently exists in the series or not).

At the moment at least, I accept the assertion that the essentially ordered series as defined cannot be infinite... that it needs a first element... such as the example I read somewhere of a lamp being plugged into an extension socket, and then another, and then another... at some point it has to be connected to the power... the first cause as it were... in order for the light to come on. Or another example, which seems kind of similar, a scene from the comedy Allo Allo... they're digging a tunnel, starting in a graveyard, and someone asks 'where do you put the dirt from the tunnel?', 'we dig graves', 'well where do you put the dirt from the graves?', 'we dig other graves'. End. Seemed kind of apt

Anyway, I don't have any objection to this logical concept of an essentially ordered series and the assertion that it has to be finite. Others with a formal logic/mathematical background may know better and I'm open to correction on that, but as it stands it seems perfectly logical to me as a concept. That's not the problem... the problem, or at least potential problem from both mine and my dad's perspective is firstly that it seems we're being asked to view causation in the real world in this highly unintuitive way (where an accidental ordered series is a far more intuitive view of causation), without any justification as to why, and that is a particularly big ask because several of the Five Ways rely on this essentially ordered series concept, not just one so it's something we realistically need to address before we even get into any of the particular Five Way arguments. The second problem is the potential circular reasoning that comes from the fact that the Bible seemingly describes exactly the same thing as the essentially ordered series, in Hebrews 1:3 "The Son is the radiance of God's glory and the exact representation of his being, sustaining all things by his powerful word", making Aquinas' reliance on the concept, as my dad put it 'suspect'.

So basically we just want to know where the idea of the essentially ordered series came from, and how it is justified in the arguments.

Also, I'd be curious to see if you have any more illustrative examples of a real world essentially ordered series... arm>stick>rock seems kind of limited and not totally helpful. My dad, looking at this, gave the example what if the arm move the stick which moves the rock which falls off a cliff into a pool of water and causes ripples. His argument being that once it's fell off the cliff it's no longer being moved by the stick and has therefore changed from an essentially ordered series into an accidentally ordered series. But I'm guessing that you may respond to that with something like its a different stack as it were of sustaining causality in each and every moment (ie a different essentially ordered series in each and every moment for each and every thing)... so while the arm is moving the stick moving the stone, that's one stack, once it reaches the edge of the cliff it perhaps becomes another stack, stone>gravity>?... something like that, is that what you mean?