Aquinas's argument from Contingency revisited

[sensibletheist]

What do you think about this argument;

1) The universe exists contingently.
2) If the universe exists contingently then it is possible for it to not exist.
3) The universe has an infinite past.
4) If the universe has an infinite past then every possibility regarding the universe would have been actualized in the past.
5) Therefore, given the universes contingent existence and its infinite past it should have ceased to exist some time in the past.
6) The only way to explain why the universe exists is by positing a necessary being which could have sustained the universe throughout an infinite past.
7) Therefore a necessary, extremely powerful, being exists.

The beauty of this argument is that it assumes what many atheists use to get around other cosmological arguments, that the universe is eternal in the past. If one combines this with Kalam, one could get a deadly two pronged assault on atheism.

[Leonhard]

I'll give it a short spin. I won't defend these points, these are just my current opinions.

1) The universe exists contingently.

Shaky premise, this would have to be defended. Its not enough to simple argue that its epistemically possible that the universe exists contingently, you'd have to defend that the metaphysics of our world corresponds to that case and this looks like an icky task. Modern physics makes this especially hard since particle fields don't cease to exist at any point, ignoring gravity singularities of course. Physical fields can change, but they don't turn into nothing. Not granted.

2) If the universe exists contingently then it is possible for it to not exist.

No problem here, as I see it.

3) The universe has an infinite past.

Granted for the sake of the argument, though this is actually a point I'm less than certain about.

4) If the universe has an infinite past then every possibility regarding the universe would have been actualized in the past.

You can draw an infinitely long line on a two dimensional grid without ever visiting all the point. In fact it can be proven that no matter how you draw the line, even if you make it infinitely long, you won't visit all the point. Despite all your attempts It'll always be able to pick a point that has never been visited. It could be the case that something similar was the case with the set of all possibilities for our universe. It seems that there's far more ways that this could be the case than not. Don't know if this is a strong point, but you'd have to work this out. Not granted.

5) Therefore, given the universes contingent existence and its infinite past it should have ceased to exist some time in the past.

6) The only way to explain why the universe exists is by positing a necessary being which could have sustained the universe throughout an infinite past.
7) Therefore a necessary... being exists.[/quote]

No problem here, its a simple deduction from the premise, except that you've slid the 'extremely powerful' qualifier into the conclusion. I snipped it out of the quote above, otherwise the argument would have been fallacious. The argument, if the premises are true, implies the existence of 'something' that prevents the universe from not existing. This wouldn't be a god-of-the-gaps fallacy in my opinion.

Since I believe that some of the premises are false, the argument lends no strength (for me) to the conclusion.

[Soyeong]

1) The universe exists contingently.
2) If the universe exists contingently then it is possible for it to not exist.
3) The universe has an infinite past.
4) If the universe has an infinite past then every possibility regarding the universe would have been actualized in the past.
5) Therefore, given the universes contingent existence and its infinite past it should have ceased to exist some time in the past.
6) The only way to explain why the universe exists is by positing a necessary being which could have sustained the universe throughout an infinite past.
7) Therefore a necessary, extremely powerful, being exists.

The third way is taken from possibility and necessity, and runs thus. We find in nature things that are possible to be and not to be, since they are found to be generated, and to corrupt, and consequently, they 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 have begun to exist; and thus even now nothing would be in existence — which is absurd. Therefore, not all beings are merely possible, but there must exist something the existence of which is necessary. But every necessary thing either has its necessity caused by another, or not. Now it is impossible to go on to infinity in necessary things which have their necessity caused by another, as has been already proved in regard to efficient causes. Therefore we cannot but postulate the existence of some being having of itself its own necessity, and not receiving it from another, but rather causing in others their necessity. This all men speak of as God.

There is no need to posit an infinite past for Aquinas' argument to work.

[sensibletheist]

In defense of 1 its unclear to me how one could say the universe could exist necessarily, or that even part of the universe exists necessarily. No philosopher that I am aware of holds to such an odd position. For to say that this is the case would be to say that the fundamental particles of the universe which are constantly changing and are arranged in different ways. How could these exist necessarily? And if not all of them exist necessarily, then do only some of them exist necessarily? If so which ones? And why those ones? The point is there is absolutely no evidence that our universe exists necessarily, all the evidence points towards a contingent universe.
See; http://www.reasonablefaith.org/is-pa...ecessary-being

In defense of 4 your argument seems to go against the way time works, time passes moment by moment. If there is an infinite past, time would require that every point is visited. But regardless, we aren't talking about a single point but a single possibility which could become actual at any point in the infinite past. So that as long as there is an infinite number of points, that possibility must actualize.

[sensibletheist]

Oh and if a being is capable of sustaining a universe, it is extremely powerful, I figured that would be a given.

[Leonhard]

Its bad form to respond to someone who said that he wouldn't give a defense of his argument, I'll make a short defense then. You're free to repond to it afterward, but I won't get back to this argument for a while. I'm spending some time in another thread.

In defense of 1 its unclear to me how one could say the universe could exist necessarily, or that even part of the universe exists necessarily. No philosopher that I am aware of holds to such an odd position. For to say that this is the case would be to say that the fundamental particles of the universe which are constantly changing and are arranged in different ways. How could these exist necessarily? And if not all of them exist necessarily, then do only some of them exist necessarily? If so which ones? And why those ones? The point is there is absolutely no evidence that our universe exists necessarily, all the evidence points towards a contingent universe.
See; http://www.reasonablefaith.org/is-pa...ecessary-being

I guess this is the scattershot question type of response. I'll do my best to make sense of it charitably. If you believe that are no philosophers who hold to this position, then I suggest reading around a bit more. You need to rub elbows with naturalists and read their works. I think I remember Bertrand Russell holding to this position, when responding to Leibniz Cosmological argument. Individual parts of existence had contingent existence, but the totality of necessary existence in his counter-argument. He argued that it was a fallacy of composition to assume that because individual particles enjoy contingent existence, the whole universe would as well. In light of modern field theory I agree.

There's a sentence malfunction in your paragraph that I can't parse: 'For to say that this is the case would be to say that the fundamental particles of the universe which are constantly changing and are arranged in different ways'. This nonsense sentence should has the same flaw "What's the difference between a penguin? It wears neither a tie". I think you're missing something there.

Asking 'How could these exists necessarily?' is an argument from ignorance. Particle fields exist, and the laws of physics don't describe any situation where they wink out of existence. The universe we observe correspond to one arrangement of these fields. That's about it really (barring new discoveries in physics), you can wind the clock back infinitely far without the equations suddenly telling us "At this point all the fields cease to exist". The only situation similar is when Big Bang cosmology implies a singularity, but since your argument presupposes an infinite past you can't use this approach in your argument. I won't respond to the link in this thread. If you feel Craig made an argument you can use, state it here.

In defense of 4 your argument seems to go against the way time works, time passes moment by moment. If there is an infinite past, time would require that every point is visited.

Why? I just showed you a counter example where even if you had an infinitely long line, you wouldn't pass through all points. Time could be made up of an absolute infinite number of points, and the possible arrangements of the universe could be an infinity of a higher cardinality. In that case no matter what, you wouldn't have tried all possibilities. You're also assuming the A-theory of time, which might become an unstated major premise in your argument. If your argument requires this conception of time, then you should state it. If you don't like the concept of a continuous time, then you can image the line as being made up of discrete points a finite distance from each other.

But regardless, we aren't talking about a single point but a single possibility which could become actual at any point in the infinite past.

Switching the label from 'point' to 'possibility' doesn't change the counterexample. Imagine that for the two-dimensional grid with reel number axis, each point corresponds to a unique possible state of the universe. One of them is the possibility that the universe doesn't exist. There's an infinite number of ways to draw an infinitely long line that doesn't pass through that point. However your argument assumes that if time is infinitely long, then it will pass through all the points. It can't. Therefore the counterexample holds.

[Soyeong]

You can draw an infinitely long line on a two dimensional grid without ever visiting all the point. In fact it can be proven that no matter how you draw the line, even if you make it infinitely long, you won't visit all the point. Despite all your attempts It'll always be able to pick a point that has never been visited. It could be the case that something similar was the case with the set of all possibilities for our universe. It seems that there's far more ways that this could be the case than not. Don't know if this is a strong point, but you'd have to work this out. Not granted.

Because you have no problem with the possibility of every contingent not existing and this possibility entails an inherent tendency to occur given enough time, then is absurd to suggest that it is both possible and that over an infinite amount of time it will never happen. If there is not an infinite amount of time and this series of contingent had a beginning, then this beginning must have had a cause, which must be something non-contingent, which is what he is trying to prove in the first place.

[GioD]

I think I remember Bertrand Russell holding to this position, when responding to Leibniz Cosmological argument. Individual parts of existence had contingent existence, but the totality of necessary existence in his counter-argument. He argued that it was a fallacy of composition to assume that because individual particles enjoy contingent existence, the whole universe would as well. In light of modern field theory I agree.

If a single part of the universe is not necessary the entire universe is not necessary because the universe is the collective of all space, time, matter, energy, and forces, and without that, it wouldn't be the universe, but a different universe.

Particle fields exist, and the laws of physics don't describe any situation where they wink out of existence. The universe we observe correspond to one arrangement of these fields. That's about it really (barring new discoveries in physics), you can wind the clock back infinitely far without the equations suddenly telling us "At this point all the fields cease to exist".

And what about a possible world where the laws of physics are different?

[robertb]

What do you think about this argument;

1) The universe exists contingently.
2) If the universe exists contingently then it is possible for it to not exist.
3) The universe has an infinite past.
4) If the universe has an infinite past then every possibility regarding the universe would have been actualized in the past.
5) Therefore, given the universes contingent existence and its infinite past it should have ceased to exist some time in the past.
6) The only way to explain why the universe exists is by positing a necessary being which could have sustained the universe throughout an infinite past.
7) Therefore a necessary, extremely powerful, being exists.

The beauty of this argument is that it assumes what many atheists use to get around other cosmological arguments, that the universe is eternal in the past. If one combines this with Kalam, one could get a deadly two pronged assault on atheism.

For premise 1, I am with Leonhard as far as the probability is concerned, but I would grant the possibility that the universe exists contingently. In fact, I might even say that it is possible that everything that exists, exists contingently on some level. This probably reduces to the question of "Why is there anything at all?".

To simply posit that the universe has an infinite past is difficult as our universe seems to have a finite past. So i am not sure I would accept this premise as stated.

I do not think that premise 4 is true so this kind of kills 5. Another issue, besides the issue that Leonhard correctly described, is that merely positing that the universe is contingent (premise 1), does not necessarily mean that non-existence remains a possibility if existence is, nor does it mean that existence remains a possibility if non-existence is.

Number 6 assumes it's conclusion (7).

[robertb]

Because you have no problem with the possibility of every contingent not existing and this possibility entails an inherent tendency to occur given enough time, then is absurd to suggest that it is both possible and that over an infinite amount of time it will never happen. If there is not an infinite amount of time and this series of contingent had a beginning, then this beginning must have had a cause, which must be something non-contingent, which is what he is trying to prove in the first place.

I do not think that "this possibility entails an inherent tendency to occur given enough time" necessarily follows from "the possibility of every contingent not existing". In other words, simply stating that x is contingent does not imply that if x then not x is a possibility.

[Soyeong]

I do not think that "this possibility entails an inherent tendency to occur given enough time" necessarily follows from "the possibility of every contingent not existing". In other words, simply stating that x is contingent does not imply that if x then not x is a possibility.

Sorry, I phrased that wrong, but I realized it too late to change it. Possibility entails an inherent tendency to occur given enough time follows from an Aristotelian understanding of what "possibility" means. It makes no sense to say both that something is possible and that it will never have given enough time.

[technomage]

1) The universe exists contingently.

Unproven (and unprovable) assumption. We know that things in the universe exist contingently--we do not know about the universe as a whole.

3) The universe has an infinite past.

Specifically false. See Age of the Universe.

4) If the universe has an infinite past then every possibility regarding the universe would have been actualized in the past.

False. Just because something is possible does not mean that probability will cause that event to occur--probability is blind.

If one combines this with Kalam, one could get a deadly two pronged assault on atheism.

Kalam is also not all it's cracked up to be.

[technomage]

its unclear to me how one could say the universe could exist necessarily, or that even part of the universe exists necessarily.

Philosophy sits by itself and ponders what it knows about the world. By itself, philosophy is sterile, because it can only extrapolate from known facts. Philosophy cannot discover unknown facts.

Try science--science discovers what is unknown about the world.

[GioD]

Philosophy sits by itself and ponders what it knows about the world. By itself, philosophy is sterile, because it can only extrapolate from known facts. Philosophy cannot discover unknown facts.

Philosophy can and has discovered facts. Philosophers discovered the principles of non-contradiction and excluded middle, neither of which in principle could be deductively proved by science.

[GioD]

Unproven (and unprovable) assumption. We know that things in the universe exist contingently--we do not know about the universe as a whole.

As I pointed out above, since the Universe is essentially a set if one thing in the Universe is unnecessary then the whole Universe is unnecessary.

Specifically false. See Age of the Universe.

The age of the Universe only applies to the post-big bang universe. I reject an infinite past but this is not a good thing to appeal to, with concepts like the multiverse and cyclic universes invalidating appeal to the age of the Universe.