The Fifth Way: Argument from Design

All sort of reality doesn’t necessary follow laws of nature, such as chaotic universe. One needs to prove that such a universe cannot exist. Our ordered universe could be just an example of many different universe. We wouldn’t be here to ask such a question if our universe was chaotic. That is all that one can say: one possibility among all other possibilities.

Essentially, the 5th argument is not an argument from ignorance but rather an inductive argument. As such, the argument suffers the weakness of all inductive arguments, i.e., any statement that claims to hold for all instances cannot be established as definitely true by a finite number of observed instances. More importantly, as argued earlier, the perspective of the Aquinas’ critics must be taken into account.

For the scientist, an unobserved but necessary cause in order to explain observed effects is often called euphemistically a brute fact rather than admit to one’s ignorance.

For the philosopher, brute fact is meaningless and ignorance is admitted; the causes observed are insufficient to fully explain the effect.

For one who has faith that seeks understanding (theologian), the unobserved cause is often called God. The 5th argument is in the book titled Summa Theologiae, not Summa Philosophica or Summa Scientifica. (My apologies to Latin scholars.)

I think that we can agree that Aquinas’ Fifth Way is the culmination of a set of arguments meant to prove the existence and characteristics of a first cause. Specifically the Fifth Way is meant to prove that the first cause must be intelligent. But to do this it simply makes the assertion that absent an intelligent cause it’s impossible for any system, no matter its characteristics, to produce order.

Aquinas makes no attempt to justify this assertion, he simply states it as a given…no process can produce order unless directed to do so by an intelligent first cause.

There’s simply no reason to believe, nor does Aquinas even attempt, to prove that this is true. In spite of the fact that any number of natural processes produce order with no apparent intelligent cause at all.

Take for example the regular motion of celestial bodies such as planetary motion about the sun. This regularity can be explained by the principle of least action which is a variational principle which gives us the equations of motion of the planets. It is not necessary to appeal to some supernatural final cause existing in heaven. The principle of least action can be derived quite easily from what a force is.

Efficient causality: B is caused by A.
Final causality: A causes B.

Ultimately you cannot explain causal regularity with appeal to efficient causality alone, because it is nonsense to say that there is nothing about A that causes it to produce B or tend to B or to produce any end at all. What St. Thomas is drawing out is that for that tendency A has towards B is a relation that exists regardless of whether B really exists or not. It’s a relation between two objects which don’t exist or between one object which exists to one object which doesn’t. And B is not in any manner formally in A, and a relation between an object to one that doesn’t exist is not something concrete at all. You will not find B anywhere in A in any really existing way. The relation is virtual or intelligible only, and we can understand this clearly as the only relation between a builder and the house he intends to build prior to the house existing is that the end is intelligibly in his mind. But many things lack intelligence and yet still cause certain ends or effects anyway. If they do not have an intellect by which the ends are conceived, then the only explanation for these relations being inherent in their natures is for an intelligence being the cause of those natures such that it can concur with them obtaining their ends.

@IWantGod, I wanted to take a moment and speak to a bit of a difference between St. Thomas’ approach and Jacques Maritain’s approach. Maritain’s (based wholly on the article provided above) is stronger in the conclusions it makes because he is taking the Principle of Sufficient Reason as being able to be separately demonstrated, so its truth can already be known to be true (as metaphysical background material) before one begins the Fifth Way. I don’t believe St. Thomas does the same, exactly. St. Thomas points to causal regularity as support for there needing to be a sufficient reason of explanation. That is, he brings up causal regularity to point out that things do not behave as we would expect (random, without regularity, etc…) if the PSR was false. At least, that’s my simplistic take at this moment.

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No… it’s basically saying that to have science at all causes which lack intelligence must bear some relation to things which don’t yet exist, and that the only mode of existence for such a relation must be intelligible, otherwise there would be no such relation such that causes could arrive at any determine ends at all.

You might disagree, but it’s not a “gaps” argument, it’s a “this is necessary for scientific methods to be coherent (which they are) at all”.

No, you’re drifting into Paley’s argument about complexity and complex systems again. The Fifth Way is that any cause lacking intelligence can produce an effect or end at all (without which you couldn’t have any notion of a system to begin with).

To quote from the previously provided article from Strange Notions, " St. Thomas Aquinas wrote his five ways to God’s existence in the very first pages of his Summa Theologiae (1265-1274), the finest, most mature synthesis of his philosophical and theological thought – a work designed both for educated laity and seminarians. Since God’s existence is the foundation on which logically rests the entirety of his multiple volume masterpiece, giving but a short paragraph’s treatment to each “way” clearly signifies that no complete scholarly demonstration was ever intended. Rather, the “ways” are merely short summaries of St. Thomas’ take on classical arguments his students already knew well."

The Fifth Way has its justifications. And I’ve tried to go over some of those at length at various points in this topic. Don’t make the error of thinking his “short summaries” are all St. Thomas had to these.

Well that’s just not true. The Argument from Motion, for example, has necessary corollaries that require the Prime Mover be unique, immutable, eternal, omnipotent, intelligent, omniscient, perfectly good, necessary, and acting by free choice. Same for the Argument from Efficient Causes and the Argument from Contingency. Maritain’s version of the Fifth Way would also entail these things a bit more clearly than St. Thomas’ presentation does.

This is what is denied. The sun rises every day. Thousands of years ago, people believed their must be a purpose. Apollo riding his chariot and so forth.
Now we know better. The sun rises every day because of orbital mechanics.
Aquinas says that there still is an intelligent purpose behind the these mechanics - a designer if you will.
But this is simply an assertion, and there are numerous, if not infinite counter-examples.
For example, the sun rises because of the laws of physics and mathematics.
You do not need an intelligent agent to create those laws - they just are. They are “self-organizing”.
As I said, you can then claim those laws of nature are “God”. That resolves the fifth way. But you cannot make a claim that these laws ‘emerged’ from an infinitely intelligent and powerful entity. That simply does not follow. If you want to believe it does, you may - but it is not a philosophical proof.

Consider this to simplify things. 3+4=7. Do we need to postulate an infinitely powerful and intelligent personal agent to guarantee that 3+4=7? No - just as you can say “God” is timeless and spaceless and so forth, I can say the same about ‘math’. All the fifth way demonstrates is that “Math=God” or “God=Math”. And if you want to worship math and nature in and of itself, you can - many people do (we call them pagans).

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The problem is your stuck on “this is how nature is observed to work,” and thinking that Aquinas is saying “that’s too complex to arise by natural means.” You’re not presenting counter examples, you’re presenting natural examples that are what we would expect given the Fifth Way. The sun rises every day from orbital mechanics. GREAT. We know. That’s not the issue. The issue is that orbital mechanics and any other mechanics or physical notions only make any sort of coherent sense in terms of ends somehow being in their causes. Not some type of grand purpose. The fact that one billiard ball can strike another. The fact that an electron has (apart from other types of interfering forces) moves towards a positive charge and away from other negative charges. Any type of specific effect produced.

You are not even addressing what I’m writing you’re so hung up on some misconception of what this is even about you keep presenting specific examples as if they are somehow counter to the point. It’s not about what physical systems can produce but about how it’s even coherent that there be such physical systems or any particular effects from causes at all.

I’m not even bashing my head against the wall because you disagree. It’s because you’re not even speaking to the argument.

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I don;t know why you keep saying this. As I said, we are not breaking any new ground here. The fifth way has been refuted for centuries. Natural self-order is only one refutation. It’s one I think makes perfect sense. You say orbital mechanics only “makes sense” if an end is somehow within it’s “cause”.
Fine - the end result of orbital mechanics is intrinsic in the bodies undergoing the phenomenon.
It’s you conclusion that makes no sense - that such an end MUST be the result of an intelligent, all-powerful, all-knowing agent. There is no such logical connection. Why cannot the “end” simply be?
Your only response is ‘because’.
Aquinas says everything in the universe has a goal, an end, a “purpose” - a design. He then makes an unjustified leap to map those ends to the theist God. This simply is not a valid step.

Well, no, I would think post# 205 in this topic (just to name one) does a lot more than simply say “because”. But you quoted from it, didn’t say anything about the actual argument, and then cited examples that I agree we observe in nature and are non-sequiturs.

Let’s try something different.

You write that there are laws of physics and mathematics. I’d like to focus on physics instead of going off on a tangent of mathematics, if you will (maybe later we can revisit). What exactly is a “law of physics”. I’m not looking for you to name a specific law. I’m familiar with them. But what are “laws of physics” as a general category? What are you referring to by the term?

OK, let’s start with gravity. Two objects are attracted inversely squarely by distance proportionally to their masses (assume I got it right). The refutation of self-organization simply says that “design” or “end” just is. Just as you can say God just “is”. If Aquinas can claim God is the source of all purpose - we can simply say that the law of gravity is the source of orbital mechanics.
We are not denying the logic of the fifth way (that would be a different refutation), but simply that the conclusion of an omniscient, omnipotent agent does not follow.

That’s a particular example, but what exactly is a law? Let me provide a few proposals to show what I mean.

  • When God causes an effect to happen on specific occasions.

  • Tendencies intrinsic to the natures of things.

  • Laws are things in themselves that act on other things to make them act certain ways

  • Nothing more than descriptions we make of observed regularities.

There’s probably some other options but I hope that helps provide the gist of my question. And feel free to use your own wording.

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What is natural self order? How does that explain the laws of physics? How does it address the argument?

There is a real relationship between particular things and the ends to which they are in act.

The ends are not actually present in particular things and only potentially until a thing realizes that potential.

But we must still hold that these relationships really exist. And so we must ask how these relationships exist when their ends are not actual. We cannot say that the end to which a thing is in act is absolutely nothing because then it would become nothing. We cannot say that the end is actually present in a particular thing at the same time because then it would be unintelligible to speak of a final cause. Thus the only way to speak intelligibly of the relationships we describe as the laws of physics is to say that a thing finds it’s natural end because an intellect has ordered nature to behave in that way and is sustaining the laws of physics with it’s intellect.

I don’t think so. I think it is the principle of least action which provides the equations of motion and thus the regularity of planetary orbits.

The principle of least action has proven useful to explain many physical laws.

What is the principle? Not what are its effects or what it says. I mean what actually is it? Please see post #213 in this topic. I’m asking you the same question I asked jan. I’ll link you to post #213:

That doesn’t explain why there is such a thing as the laws of physics. I’m asking a metaphysical question not a scientific one.

Generally you minimize the time integral of the Lagrangian to get the equations of motion. The Lagrangian is simply the kinetic minus the potential energy which follows from the Newtonian definition of forces acting on a planet or particle, etc. The regularity of the planetary orbital motion follows from taking the stationary path of the system between times t1 and t2 and configurations q1 and q2 .

That’s not what I asked for. I asked for: “What is the principle? Not what are its effects or what it says. I mean what actually is it? Please see post #213 in this topic. I’m asking you the same question I asked jan.”

The equation or “regularity” of motion follows from minimizing the action S where S is the integral over time of the Lagrangian or T - V.
T the kinetic energy
P the potential energy.

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