Richard Swinburne on Probabilities and the Anthropic Principle

When I first read the selection below I was a believer and thought what Swinburne wrote on this topic in his book, The Existence of God (1979 ed.), was excellent. No longer do I think so.
Suppose that a madman kidnaps a victim and shuts him in a room with a card-shuffling machine. The machine shuffles ten decks of cards simultaneously and then draws a card from each deck and exhibits simultaneously the ten cards. The kidnapper tells the victim that he will shortly set the machine to work and it will exhibit its first draw, but that unless the draw consists of an ace of hearts from each deck, the machine will simultaneously set off an explosion which will kill the victim, in consequence of which he will not see which cards the machine drew. The machine is then set to work, and to the amazement and relief of the victim the machine exhibits an ace of hearts drawn from each deck. The victim thinks that this extraordinary fact needs an explanation in terms of the machine having been rigged in some way. But the kidnapper, who now reappears, casts doubt on this suggestion. 'It is hardly surprising', he says, 'that the machine draws only aces of hearts. You could not possibly see anything else. For you would not be here to see anything at all, if any other cards had been drawn.'Link
What needs to be understood is that the odds for any ten cards drawn by this machine were exactly the same, 1 in 145 sextillion I'm told. That is, the odds that this machine would have instead drawn ten Queen of Spades were exactly the same as drawing ten Aces of Hearts, or any other combination of cards. So any ten cards drawn in the order they were drawn were equally, well, impossible. Who would bet much money on predicting which cards were drawn in what order, right?

In this case the cards saved a person's life. This expresses the anthropic principle in that if those particular cards had not been drawn that victim could not possibly be alive to see them just as if our universe turned out differently we as human beings could not be here to see it either. Okay so far?

Here then is Swinburne's conclusion:
The fact that this peculiar order is a necessary condition of the draw being perceived at all makes what is perceived no less extraordinary and in need of explanation. The teleologist's starting-point is not that we perceive order rather than disorder, but that order rather than disorder is there. Maybe only if order is there can we know what is there, but that makes what is there no less extraordinary and in need of explanation.
But if we return to Swinburne's analogy let's instead kidnap 1 in 145 sextillion life forms and match them up with 1 in 145 sextillion combinations of cards such that for every set of ten cards drawn the corresponding life form will live to see it. So it would hardly be surprising that if any given set of cards are drawn then the corresponding life form sees them. That's what Swinburne fails to understand.

Let me put this in a better context since I know the odds that our universe would produce life forms in every scenario is impossible. So here it is: If the odds are 1 in 145 sextillion that the universe turned out differently then the odds are 1 in 145 sextillion that the universe turned out differently. And that's all there is to his logic! So it's a tautology, true by definition. The fact that it did turn out the way it did such that we see the universe is not surprising since if it had turned out differently we wouldn't be here to observe it. The fundamental flaw in his line of reasoning is that there are other life forms that would exist if it had turned out differently, although what they might look like we don't have much of a clue. If, for instance, nine Aces of Hearts were drawn by this machine and one King of Hearts then the life form that represents those drawn cards would be able to see it, and so forth and so on.

Cheers.

HT: BK

33 comments:

philip m said...

Read the whole chapter for the 2004 edition. The reasoning is based on the need to explain there being a universe where any of the heavy elements can form, regardless of whichever ones are actually capable of being a base for life. It is not particular to the form of life being human beings, or carbon-based, only to there being a universe capable of supporting some form of life or other.

Anonymous said...

phillip m, the link provided takes us to the 2004 edition.

Tell me this: If someone were asked to calculate the odds 500 hundred years ago that people fitting the description of you and I would be typing these exact words right at the exact times we did, wearing what we've got on in rooms that look just like they do now what would they be?

Impossible to caluculate?

And yet here we are. Do these odds prove we need a God to account for this happening?

Didn't think so.

philip m said...

I didn't even know there was a link, but that's not the whole chapter. His discussion of the science behind the need for explanation gives you the answers you're looking for.

I am not getting your point. You are trying to draw an analogy, but I don't think it is parallel to the case we're discussing. The explanation for a specific course of human actions in history is of course the choices of each of the individual humans. (Or, if you are a determinist, the physical antecedents of the universe.)

If you think the form of theistic arguments are "P is improbable, therefore P is explained by God" then you are quite confused about why theists believe in God. Do you really think that theists think that _any_ coincidence is an equally good argument for God's existence?

The problem is that you are taking the argument out of the context in which it is made: something Swinburne points out at the beginning of the book to be a grave mistake. He wrties, "Sometimes, however, philosophers consider the arguments for the existence of God in isolation from each other, reasoning as follows: the cosmological argument does not prove the conclusion, the teleological argument does not prove the conclusion, etc., etc., therefore the arguments do not prove the conclusion."

In chapter six Swinburne discusses the reasons God has to bring about humanly free creatures. That's what you are looking for. It is therefore not just _any_ improbability that needs explaining, but improbability with an independent fact that needs explaining: in this case, that there are "humanly free creatures." If it is probable in the case that God exists that there are humanly free creatures, and improbable in the case God does not exist that there are humanly free creatures, then we have good reason to believe that God exists.

Take the card game bridge as an analogy. In bridge any hand that you are dealt is equally improbable. But you are going to suspect cheating if the dealer winds up with a perfect bridge hand. Why? Because in that case the bridge hand accomplishes an independent purpose, i.e. there is an independent fact in the case that makes it more than generic improbability.

So reading chapter 6 and then the entirety of chapter 8 should sort out any worries that you had in this post. If you emailed him this critique, he would just point out the places to read in his book.

Rob R said...

The fundamental flaw in his line of reasoning is that there are other life forms that would exist if it had turned out differently, although what they might look like we don't have much of a clue.

unsupported assertion.

Rob R said...

Just out of curiosity John, are you an antirealist about probability?

From a qm perspective, most biblical miricles are actually physically possible but are profoundly and extremely unlikely to have occured via random quantum flunctuations. So for one to insist that they couldn't have happened on the basis of their improbability, I could say something like: "If someone were asked to calculate the odds 500 hundred years ago that people fitting the description of you and I would be typing these exact words right at the exact times we did, wearing what we've got on in rooms that look just like they do now what would they be?"

Piratefish said...

I arrive at exactly the opposite conclusion when I look at this argument. We're here because of the fine-tuned universe, another universe that's fine-tuned differently will produce a different life form, or no life form at all, but this one does, and we're here to see it. This argument just doesn't work out as Swinburne intended.

Shane said...

Swinburne is right that our existence demands an explanation, and I guess, given the enormous size of Africa, snowflakes on the summit of Kilimanjaro probably feel they demand an explanation for their existence too.

If we accept (as I find unavoidable, but plenty of people disagree) Max Tegmark's argument that the universe *is* a mathematical structure, observable by "self-aware substructures" within it, then it is not surprising *at all* that we exist in a universe that is just right for our existence (despite the fact that we are eking out a pretty damned marginal existence in this one as it stands, confined as we are to the shell of a minuscule bubble in the immensity of space).

But setting that aside, if Tegmark is correct, then we can see that Conway's Game of Life can be considered a valid set of universes, even simple structures like the Fibonacci sequence are "universes". The interesting ones, of course, are going to be the ones that are Turing-complete - i.e. they can host a universal computing machine. Ours can, obviously, but there is no reason why "universes" in general need to have the kinds of physics we see here - that could well just be a quirk of the mathematical equation that gets us from one Planck tick to the next...

Anonymous said...

Phillip m, I have read all of Swinburne's book and his cumulative case and it all falls apart in several places. I have produced a counter- cumulative case myself in my book, WIBA. Check it out sometime.

Cheers

BK said...

No, I don't agree. His thought experiment is designed to show that it is not legitimate to simply say that "of course the odds are all that way or we wouldn't be here to see it." Your post does nothing to counter his point.

Even so, you are correct that using his numbers the odds are 1 in 146 sextillion that the cards would turn up all the card identified. If the cards don't turn up that way there is no way that the person survives. But it isn't the case that any other combination of the cards ends up with him surviving. Likewise, many of the finely-tuned features of the universe are not about whether life like ours could occur, but whether any conceivable type of life could occur. Thus, it is not a tautology at all.

By the way, take a look back at our discussion on the CADRE blog related to the box discussion when you have some time.

Realityvist said...

Rob R, I should point out that "God exists" is also an unsupported assertion. So is the claim that biblical "miracles" really happened.

@phillip m - "If it is probable in the case that God exists that there are humanly free creatures, and improbable in the case God does not exist that there are humanly free creatures, then we have good reason to believe that God exists."

This is a completely meaningless statement. I don't even know to which god you are referring - is it Yahweh, is it Vishnu or is it a deistic god? I will assume Yahweh. If you substituted "Zeus" or "Xenu" or "Two alien scientists in a lab" instead of "God", the problem with the statement should be obvious.

"If it is probable in the case that Zeus exists that there are humanly free creatures, and improbable in the case Zeus does not exist that there are humanly free creatures, then we have good reason to believe that Zeus exists."

Zeus isn't real, but Yahweh is? If Yahweh is indeed real, you can change my mind at anytime by showing actual evidence, instead of games with words. Yahweh, Zeus, Xenu etc: in reality are just entities created by the minds of men.

Piratefish said...

BK>

I don't think you understand John's argument, the same for Swinburne's, please understand them before posting ok?

Rob R said...

reposted because the original was addressed to the wrong person

Realityvist,


I should point out that "God exists" is also an unsupported assertion.

In the context of this discussion, the fine tuning argument is the support for the assertion of God's existence. Whether or not it succeeds doesn't change the fact that it has been supported.

John is suggesting it doesn't succeed for certain reasons. one of those reasons is unsupported.

Rob R said...

Just another thought John. The problem with your criticism is that you fail to understand that with this analogy or with the actual fine tuning argument, the 1 in the infinitesimal probability is special. It's improbability alone isn't what makes it special. The fact that it is 1) highly improbable AND 2) the only probability for survival is what is relevent.

It's not enough to say that low probability events happen all the time. The question is why should we think these probabilities have a comparable specialness. The fact that we are specifically having this conversation, that we have our specific DNA and were even born as opposed to someone else who wouldn't be having this specific conversation isn't comparably special. What establishes that brow raising specialness? In the context of swinburne's example, it's that the kidnapper had previously told the man what cards had to be shuffled for his survival. There was only one highly improbably combination that would work. None of the other 145 sextillion improbabilities would do. With the fine tuning consideration, the low chance that the universe had the specific combination of constants and laws that it does isn't what makes it special. It's that it's the only extremely low probability of combinations that would make life possible.

It's not enough for you to point out that low probability things happen all the time. For your further example of our having this conversation occuring here calculated from the state of events 500 years ago to compare to the fine tuning argument, you'd need something really uncanny like a scroll unearthed 500 years ago that contains precisely this very conversation. Then you have a parallel example.

Robert Oerter said...

John, I have to agree with Rob R that your answer is not very strong, or, indeed, very clear.

I think a better response would be to point out that, as Rob R said, the surprise of the victim depends on the victim knowing that the chance of ten aces of spades is 1 in 146 sextillion. (Imagine that the madman had said, "Here's a machine that will spit out ten cards. If the ten cards are not all aces of spades, you will die." Will the victim now be as surprised if the machine spits out ten aces of spades?)

This is NOT the situation in which we find ourselves with respect to the universe and its parameters. We have absolutely no idea what the probabilities are for any of those parameters.

Put the situation another way to clarify matters: Suppose 146 sextillion universes are created. How many of them will have physical parameters close to the ones we measure?

Now we see the problem. Created by what process? If we don't know what process creates universes, then we have no clue what the probabilities are for various possible universes. Perhaps our set of parameters is the only set that can ever be produced! Until we have a (tested and verified) theory of how universes are created, we can't be in the position Swinburn wants us to think we're in.

This restatement also makes it clear that God is not a solution to the problem (if it exists) either. Suppose that God creates 146 sextillion universes. How many of them will have the parameters we observe? We still have no idea what the answer is! Maybe God prefers lifeless universes, and creates a googleplex more of those than of life-containing ones. Maybe God created only one universe: ours.

The situation is exactly the same with a physical origin of the universe. Maybe the physical processes created 146 sextillion lifeless universes and our single life-containing universe. Maybe physical processes can ONLY produce our type of universe. In either case, we know that our type of universe does, in fact, exist. And that's all we know. So arguing about the (never specified) probabilities of other universes with other physical parameters seems rather pointless.

Chris Jones said...

The "1 in the infinitesimal probability" notion is more problematic for a purposeful god who purports to have options than for the alternatives. Stepping back:

1) The probability argument presupposes that this "finely tuned" universe is the only universe in which life could have arisen. Should we be specifically talking about life exactly as we know it, then perhaps. Does this preclude other life forms? I'd say not. Victor Stenger, in "God: The Failed Hypothesis" dismantles the notion that this universe is particularly special, or that the various constants do imply such a tight fine-tuning. I won't repeat those points here.

2) Returning to my point early on, let's assume for a moment that this truly is a special universe in that there is no other conceivable set of physical constants in which any form of life could have possibly arisen. This would be dire indeed for a purposeful god. That, unavoidably, would leave that god with NO choice whatsoever but to create THIS exact universe should that god wish to end up with a universe containing life. I repeat: NO choice. Were it true that this god could have selected from some number of choices in creating a universe, then there is no reason those other choices available to the god wouldn't have also been available as possibilities to have come to be anyway. Is this making sense? The fine-tuning argument is what I would call "God's Handcuffs".

3) Supposing there is some genuine limitation on the number of sets of constants that could produce a life-containing universe, and that the number of these possible sets is much lower than the number that cannot produce life, I don't see that as a problem at all. We simply don't know how many variations have been produced -- and should this universe be only one instance of some infinite number of trials in an eternal, infinite cosmos, then we should still consider it nothing short of inevitable that this universe would arise even (worst possible case, and the worst "God Handcuff" scenario) if our combination of physical constants were the ONLY one out of a gazillion possible non-viable sets.

Piero said...

Thank you, Robert Oerter and Chris. You've made some very deep and interesting points. I especially liked the "fine tuning as God's handcuffs" analogy.

Chris said...

"The probability argument presupposes that this "finely tuned" universe is the only universe in which life could have arisen."

Well this is the only universe that we know of with any certainty and we have never found life elsewhere. I think the arguments saying well there could be other universes or kinds of life are unwarranted.

Chris Jones said...

"Well this is the only universe that we know of with any certainty and we have never found life elsewhere. I think the arguments saying well there could be other universes or kinds of life are unwarranted."

Other universes and other kinds of life aren't offered as a certainty. That is offered as a possibility, a workable solution to the "fine tuning" argument. That argument suggests that a god is necessary to explain the apparent "fine tuning", and I say that the existence of other viable alternatives is ample reason not to jump to "God" as a necessary conclusion.

This is often a rather frustrating exchange in the "Fine Tuning" discussions. It goes like this:

Theist (T): The universe is fine tuned. God is the only possible explanation.
Nontheist (NT): Other universes could produce this result. God isn't the ONLY possible explanation.
T: There is no proof of other universes.
NT: Arrgh!!!

I suppose I'm justified in flipping this discussion around and suggesting that fine-tuning is evidence of multiple universes, while the "God" argument is unwarranted. We have never found God. Multiple universes appear to be an implication of the inflationary big bang model.

--Chris J (There are two of us with this name)

Anonymous said...

Thanks Robert Oerter, I appreciate and agree with your insight.

Anonymous said...

And thanks to Chris too.

Anonymous said...

Robert Oerter and others, I'd appreciate your insight on this scenario.

Cheers.

Realityvist said...

@Rob R - "In the context of this discussion, the fine tuning argument is the support for the assertion of God's existence. Whether or not it succeeds doesn't change the fact that it has been supported."

By "unsupported assertion" what I mean is that the assertion "God exists" is NOT supported by any actual evidence or facts. Fine tuning is NOT evidence supporting the assertion, as explained below. I don't know what else you mean by unsupported, I am using the dictionary definition. By definition, the assertion is unsupported, if the evidence doesn't succeed (in demonstrating the truth of the assertion). And it doesn't here. So "whether or not it succeeds" doesn't make sense to me.

A fine tuner's claim
1) The Universe is fine tuned, then God (Yahweh) must have done the tuning, therefore God (Yahweh) exists.
Then someone else could claim in the same vein, no, no that is not right
2) The Universe is fine tuned, then two Alien Scientists (Zoltan and Zoeb) must have done the tuning, therefore Zoltan and Zoeb exists.

Now the problem with 1) should be obvious. Now would you say "In the context of this discussion, the fine tuning argument is the support for the assertion of Zoltan and Zoeb's existence."??

By no means is the concept of fine tuning settled science. Here is a link with another link to a Physics paper if you are so inclined.
http://worldofweirdthings.com/2009/05/01/the-anthropic-principle-takes-another-hit/

There is so many other things wrong with the fine tuning argument. I will just list one more. god of the gaps - We don't know what is really going on here, so God did it.

Imagine if you will, a commenter who lived 4000 years ago. And he would say.
3) Lightning falls from the sky, therefore God must be throwing it. It doesn't just fall by itself, don't be silly.
Now here in 2010
4) The Universe is fine tuned, therefore God must be tuning it. It doesn't just tune itself, don't be silly.

Chris said...

"I suppose I'm justified in flipping this discussion around and suggesting that fine-tuning is evidence of multiple universes,"

I don't think your justified because multiplied universes is really an argument to make sense of the supposed fine tuning. Its not empirically testable.

I agree with Robert that we can never really know if the universe is fine-tuned or not.

Chris Jones said...

Me: ""I suppose I'm justified in flipping this discussion around and suggesting that fine-tuning is evidence of multiple universes,"


Other Chris: "I don't think your justified because multiplied universes is really an argument to make sense of the supposed fine tuning. Its not empirically testable. "

That, sir, was suggested by me with the utmost sarcasm. It wasn't meant to be taken seriously. My purpose in writing this was to draw attention to the vacuousness of the remark that goes something like, "Fine-tuning is evidence of God", to which I merely responded with a non sequitur of equal proportions. My remark was nearly identical to Realityvist's parody of the argument in which he is proposing that Zoltan and Zoeb are the fine-tuners.

My position is this: Taking Victor Stenger's observations into consideration (God: The Failed Hypothesis), the universe doesn't actually appear to be fine-tuned. Should there still be some imbalance of possibilities (i.e., combinations of physical constants) in which non-productive universes are more plentiful than productive ones, the explanation for that could only be deemed "unknown".

You are wrong, however, that the proposition of multiple universes only exists for the sake of explaining apparent fine-tuning. Multiple universes are an implication of several independent models produced by modern physics, resulting from the theories and not as an explanatory mechanism for fine tuning. The inflationary big bang model prooposes one form of multiple universes (re: Andre Linde's paper from the early 90s); String theory has yielded the ekpyrotic big bang model, which also entails multiple universes; and most of the non-Copenhagen interpretations of quantum mechanics (any which propose no collapse of the wave function) imply multiple universes, the most popular variant of which appears to be the "many worlds" hypothesis.

I don't have a strong position on any of these, though at the moment the inflationary model seems to have grown some legs.

Robert Oerter said...

I meant to say that most of what I wrote came from a wonderful little article by Michael Hurben over on the Secular Web. (There are several other articles there that address the fine tuning argument - I've only read a few.)

Chris Jones said...

Having back-tracked and read Robert's view, I concur that whether fine-tuning exists is unknowable at present. Stenger's arguments continue to have a great deal of significance because those open up the reality that should random combinations of constants be produced, more of those could produce something than is generally supposed by the fine-tuning advocates who suggest that changing ANYTHING would yield a nonsensical universe.

Robert's point, though, appears to be that while there could be many other productive combinations of constants, not knowing how universes form and the ultimate medium in which they form is a hurdle in knowing how many of those combinations are actually in the pool.

Ultimately, though, no matter how you look at it, no argument in favor of a god can reasonably be made.

Other Chris, I apologize for mistakenly assuming that you were arguing in favor of fine-tuning earlier on.

Chris said...

"no argument in favor of a god can reasonably be made."

That may be true but I don't think that means therefore there is no God.

Chris Jones said...

Me: "no argument in favor of a god can reasonably be made."

Other Chris: "That may be true but I don't think that means therefore there is no God."

Please point out where I've said that it does?

Chris said...

"Please point out where I've said that it does?"

I was just clarifying that just because an argument doesn't prove that God exists doesn't mean its unreasonable to believe in God existence.

Piero said...

"...just because an argument doesn't prove that God exists doesn't mean its unreasonable to believe in God existence."

True, but when no argument proves God's existence, to keep believing is mere stubbornness.

Jonathan said...

What does Neil Tyson think about Intelligent Design?

Finely Tuned Universe?

Or is life finely tuned for our universe?

There is a incredible range variations of life that exits in the most extreme conditions of our planet. Life is more adaptable to its conditions than to say the universe adapts itself to life.

But

When we have a catalog of planets (100 or so?) that we physically visited probe or manned then we can have a honest discussion if the universe is finely tuned or not.

Side note:

It coast around 500 million to film Avatar and world wide it grossed up to 1 billion.
Would you trade your ticket to see aliens on film Vs. building a probe that might find them?

Chris said...

"but when no argument proves God's existence, to keep believing is mere stubbornness"

I disagree. I don't think any argument will prove God does or does not exist. But one can look at arguments and feel it is more plausible to believe in God than a complete naturalistic explanation.

JOCAX said...

Abstract: The “Destropic Principle” is an argument that establishes that every universe is equiprobable, and the possibility of life is not a more special feature than any other. This opposes to the “anthropic principle” when it is used to argue that there is a necessity for a divinity, or multiple universes, in order to explain the configuration of our universe, particularly, the capability of harboring life.

In order to explain life in our universe, I will refute the “anthropic principle” when it is used as an argument of the necessity of a deity or multiple universes. I had already outlined this argument in my previous article on the theme, The Anthropic Principle and The Jocaxian-Nothingness” [1], but now I intend to go a little deeper in the analysis.
It is not a very intuitive argument, and that is why we should use an analogy to understand the idea behind. But first, I will summarize the anthropic principle and how it is used by creationists and religious people in general to justify God:

LOOK FOR "DESTROPIC PRINCIPLE"