According to the book ‘A shorter Summa‘, the Five ways of St. Thomas Aquinas ‘are not proofs themselves but ways, i.e., indications or summaries of proofs. The proofs themselves are elsewhere worked out in much greater detail’ . (Indications of the existence of God). But as I only have ‘A shorter Summa’ at hand, the arguments expressed in it will be the topic of this post. If the arguments are better argued in other places, the author of this book holds some of the blame. (By the way, summa means summary, like a guide-book.)
As the author says the ‘five ways are essentially one way: the “cosmological argument” or argument from the cosmos’. A cosmological argument argues from a fact of the universe to a creator of the universe. At least, that is the intent.
The first way argues from motion to a prime (first) mover. It is apparently the most manifest, that is, most obvious way. The argument presented in ‘A shorter Summa’, here presented in (roughly) standard form follows:
- It is certain, and evident to our senses, that in the world some things are in motion.
- Nothing can be in motion except it is in potentiality to that towards which it act.
- Motion is nothing else than the reduction of something from potentiality to actuality.
- Nothing can be reduced from a state of actuality, except by something in a state of actuality.
- (Therefore) whatever is in motion is put in motion by another.
- It is not possible that the same thing should be at once in actuality and potentiality in the same respect, but only in different respects.
- It is therefore impossible that that in the same respect and in the same way a thing should be both mover and moved, i.e., that it should move itself.
- Therefore, whatever is in motion must be put in motion by another.
- If that by which is put in motion be itself put in motion, then this also must needs be put in motion by another, and that by another again.
- But this cannot go to infinity, because then there would be no first mover, and, consequently, no other mover; seeing that subsequent movers move only inasmuch as they are put in motion by the first mover.
- Therefore it is necessary to arrive at a first mover, put in motion by no other; and this everyone understands to be God.
What to make of this? To the modern mind (or at least mine), this talk of actuality and potentiality seems a bit odd. But according to a shorter summa actual(ity) = fully real, complete, perfect and potential(ity) = principle of change, potential to be actual.
The first objection that jumps out could be made by any adolescent: ‘if everything has a mover, and nothing can move itself, what moves the prime mover?‘ The answer probably would be, ‘the prime mover is actual (already existing), and so not in need of prime-prime mover‘. Convenient and basically a sophisticated way of saying ‘just because’. Here stops the chain of mover by fiat.
But if you think on it for a second, it contains the idea that nothing can be part of an infinite chain, so there has to be a start of that chain. Why? No reason is given, premise 10 says but this cannot go on forever, because there would be no prime mover. But given this series of premises, and intermediate conclusions is trying to prove (or indicate) that final conclusion of a prime mover, isn’t it a bit dodgy to insert a premise that basically says, ‘without this bit of ad-hockery, we can’t get to the conclusion?’ That is, without assuming a prime mover, there’d be no prime mover. Well, yes, but that’s hardly an argument.
But why can’t we have an infinite chain of movers? An infinite chain has no beginning. The idea that if it were infinite, then there would be no movement because there would be no mover is just false. In an infinite chain of movers, there’d always be an infinity of movers in the past, for any chosen mover. So, there’d be movement just fine.
What of the idea itself of movement? This idea as presented above, that everything moving, needs a mover is presented as a description of how things are in the universe. But this is based on Aristotelian physics. And it is simply wrong. Ever since Galileo, or at least Newton, we’ve known it to be wrong. – No fault of Aristotle, a genius who did what he could with his mind and limited data and limited giants upon whose shoulders to stand. Aquinas himself was the closest his time had to a cutting edge scientific theorist, but one who couldn’t arrive at a result of no god on pain of death, atheism was right out! It wasn’t until Georg Cantor that infinity was finally adequately formalized. – Things do not need other movers to set them in motion, or change their motion. No mover is required when a body is attracted to another body and so on…Physics moves on (pardon the pun), a metaphysic that is based on a description of how things are in the world should too, but that might undermine the first way….
There is probably much more that can be said against the first way, and as a final point I’ll note that quantum vacuum fluctuations go (seemingly) uncaused from potentiality to actuality and back again too often to be remarkable.
I think, therefore, we can say the most manifest way, is a manifestly unsound argument.
‘The second way is from the nature of the efficient cause’.
- There is no case known (neither is it, indeed, possible) in which a thing is found to be the efficient cause of itself; for so it would be prior to itself, which is impossible.
- (Therefore) in the world of sense we find there is an order of efficient cause.
- Now in efficient causes it is not possible to go on to infinity, because in all efficient causes following in order, the first is the cause of the intermediate cause, and the intermediate is the cause of the ultimate, whether the intermediate be several or one only.
- Therefore, if there be no first cause among efficient causes, there will be no ultimate, nor any intermediate cause.
- But if in efficient causes it is possible to go on to infinity, there will be no first efficient cause, neither will there be an ultimate effect, nor any intermediate necessary to admit a first efficient cause, all of which is plainly false.
- Therefore it is necessary to admit a first efficient cause, to which everyone gives the name God.
This way, like the first, mistreats infinity, as if it were something that had a beginning, and also makes use of an intuitively right feeling, but at least controversial, if not simply wrong, idea of causality. Firstly, if we have a chain of causes and effects that is infinite, then for whatever cause and effect pairing we point to, there will be an infinite chain before it. There idea that an infinite chain of causes is plainly false, is plainly false. Secondly, at least since Hume, it has been arguable if every event (effect if you like), has to have a cause. As I mentioned above, quantum vaccum fluctuations occur in space, without an observable cause (and arguably without a cause). So it not impossible to posit that something kick started causes and effects at least once without itself having a cause. It is not the cause of itself, as premise 1 would have it, but uncaused. Tertium datur.
The second way, like the first requires us to reject what we know to be true. We just have to accept Thomistic assumptions in the face of reality.
As an aside, Aristotle, whose philosophy Aquinas used as a language to describe the ways, thought there were 4 causes. The efficient cause is rougly what we mean by cause these days. The other causes really aren’t causes at all as we understand the word. Just ends, or methods to acheive a result.
‘The third way is taken from possibility and necessity’.
- Since things in nature are found to be generated, and to corrupt.
- Consequently, things are possible to be and not to be.
- But it is impossible for these always to exist, for that which is possible not to be at some time is not.
- Therefore, if everything is possible not to be, then at one time there could have been nothing in existence.
- Now if this were true, even now there would be nothing in existence, because that which does not exist only begins to exist by something already existing.
- Therefore, if at one time nothing was in existence, it would have been impossible for anything to to have begun to exist; and thus even now nothing would be in existence – which is absurd.
- Therefore, not all being are merely possible, but there must exist something the existence of which is necessary.
This way has some intuitive plausiblity, but whilst I have no objections to the first 3 premises, such as they are. Aquinas helps himself to a nice wad of the fallacy of composition with number 4. Just because everything we observe (a very limited set of an unfathomable universe that existed over 14 billion years before the first human) it doesn’t follow that everthing is not possible to be. It’s doesn’t follow that the universe is necessary and has always existed. That is, just because we observe things that come and go, it doesn’t mean the universe is a thing that comes and goes.
Premise number 5 is plainly false. If something is possible to be, then given enough time, it will be. Simply because if it does not come to be at some time, then it was not possible for it to be. Richard Carrier explains this in detail here. It follows that premise 6 and 7 are plainly false too. So the third way doesn’t lead to anything.
‘The fourth way is taken from the gradation to be found in things’.
- Among beings there are some more and some less good, true, noble, and the like.
- But “more” and “less” are predicated of different things, according as they resemble in their different ways something which is their maximum. i.e. which is truest, best noblest.
- Now the maximum in any genus is the cause of all in that genus; as fire, which is the maximum of heat, is the cause of all hot things.
- Therefore, there must also be something which is to all beings the cause of their being, goodness, and every other perfection; and this we call God.
The fourth way has a healthy lump of Platonism, borrowed by Aristotle from his teacher, Plato. The idea is that for there to be more or less of something, there must be this perfect something that all other things share somewhat in. An argument beautifully lambasted by Richard Dawkins in the ‘God Delusion’ when he queried whether their was a fart genus, and all farts were caused by it, and partook in its odor (I paraphrase).
But this is nonsense. Premise 3 is clearly wrong, but understandable given Aristotle’s knowledge. Fire, firstly isn’t the maximum of all heat, and it doesn’t cause hot things, heat is movement of atoms. Perhaps we could substitute gravity? After all, gravitation collapse forces gas into a tight space, and eventually nuclear fusion, which results in hot balls of gas like the sun and the nuclear fusion is the cause of all heat, thus when I light a match, nuclear fusion is the cause…uhm no….(although previous stars generated the material of the match in a supernova.)
The idea that being and goodness are perfections is just smuggling in assumptions. Goodness is a description of how apt something is for a purpose. A knife might be quite good at cutting steak, but not at all good when disembowling someone. Perfection, at least as presented in this argument, is an ideal (Platonic idea), and unless you are a Platonist, just say no. It might have been the perfect Pavlova you had last Christmas, but was it really perfect? The fourth way never really gets anywhere again.
As another aside, the idea of predicates, genus and species, comes from Aristotle’s Categories, which is part of the Organon. Essentially a toolkit you needed to engage higher learning. A predicate, which from Greek we get our work Category (hence the Categories), was the verbal phrase joined to a noun. So, in the phrase, ‘Socrates is mortal’. ‘Socrates’ is the subject, ‘is mortal’ the predicate. Genus and species had different usage than today. In Aristotle’s work, everything came under a genus, and had it’s own species. This is understandable when you have the genus animal, and the species man. But had some very strange artifacts as argued by Aristotle, e.g., If we call an individual man ‘skilled in grammar’, the predicate is applicable also to the species and to the genus to which he belongs. This law holds good in all cases. So given that the maximum of a genus, is the cause of all in that genus, and presumably, man is the maximum of the genus animal, being a rational animal, then all animals are skilled in grammar? Mmmm….
‘The fifth way is taken from the governance of the world’.
- We see things which lack intelligence, such as natural bodies, act for an end, and this is evident from their acting always or nearly always, in the same way,so as to obtain the best result.
- Hence it is plain that not fortuitously, but designedly, do they achieve their end.
- Now, whatever lack intelligence cannot move towards an end, unless it be directed by some being endowed with knowledge and intelligence.
- Therefore, some intelligent being exists by whom all natural things are directed to their end; and this being we call God.
This way assumes that everything that exists has a purpose, and argues from this assumption that everything has a purpose and therefore it must have a purpose giver. It is a mark of, and great failing of, Aristotelian philosophy, that the perceived purpose in animal life and often real purpose human society was generalized to every thing in existence. That everything has a nature or purpose to which it aims. Evolution rules out purpose in animal life, and yes, there often is a purpose behind human behaviour, but contra Aristotle, we’re not always rational animals, and are quite often just passionate animals who do things against or in spite of our desired purposes.
But to extend this to all things? A rock acts for an end? Nuclear particles decay at some indeterminate moment for an end? Come on. Sorry, no sale. The idea that everything in the universe has a governance is not plausible. You could say the laws of physics govern everything, but the laws of physics aren’t laws of a prescriptive nature, but observed regularities. Even if you reify them as things, they have no mind, and are indifferent to everything. Not really the governing type. This way goes nowhere. It’s not worth arguing with seriously.
And that’s about it. If I’ve done the arguments injustice, I’ve done the best my knowledge and intelligence allows. If I’ve not presented the arguments well, I’ve presented them as accurately as I found them. In the end, I find that you need to already accept the Thomistic/Aristotelian axioms that are used in the above arguments, and ignore or somehow bend known facts and theories learnt in the last centuries, then maybe, but no. These ways do not indicate anything.
As a final note, a Thomist might find the five ways plausible, and good luck to him/her. But if you want a non-Thomist to find them plausible, argue from shared premises, not Thomistic premises, like natural bodies, act for an end.