This is part of a series of posts in response to "Letters to a Doubting Thomas" C. Stephen Layman.
Chapter Five of Layman's book is entitled, "A Design Argument." By this time in their dialog, Zach (our curious agnostic) and Thomas (his college philosophy major friend) have covered a priori probabilities for theism and naturalism, suggesting that naturalism comes out ahead due to its simplicity (lower numbers of both entities and types of entities), but that the two end up tied because naturalism is required to complicate itself due to arguments from religious experience. They then move on to cosmological arguments. Both of these will be covered in other posts; for now, we'll just pick up with design.
First he lays out what he means by "fine-tuned" (summarized from pages 111-112):
- If the big bang hadn't "banged" with it's precise force, the universe would have either collapsed on itself or expanded so rapidly that no stars would ever have formed. In either case, no life providing energy would have been present from entities such as our sun.
- Similarly, the balance between gravitational pull and electromagnetic forces need to be precisely what they are (not differing by more than 1 in 1040 or the sun would not be stable
- The nuclear force needs to be what it is for diversity of elements
- And so on. He states that, "Over twenty such physical parameters must have values that fall within highly restricted ranges in order for life to be present."
Before I present Layman's list of hypotheses he thinks are the candidates for explanations of fine-tuning, I want to present what I take to be his criteria for judging said candidates. Zach points out that not everything may have an explanation, and Thomas agrees:
Not everything can be explained. Whatever view we take, there will be some ultimate hypothesis—the claim that some entity has such-and-such features, and for this we will have no explanation.
But we are looking for an ultimate metaphysical postulate that will explain as much as possible. We want to go as deep as we can. Why are things as they are? (p. 114)
From here, he lists our choices for such postulates:
Naturalists are free to adopt explanations 1 through 4. (p. 115-116)
- Coincidence: Our universe might have had many different basic structures, the vast majority of which would not be life supporting. The actual structure of the physical universe is simply a coincidence.
- Physical necessity: The ultimate physical structures can be of only one form, and that is the form our universe takes.
- Percentage of possible universes: Some large percentage of the total number of possible physical universes is life-supporting (i.e., the basic structures in those possible universes would support life if the universes were actual). Hence, any actual universe has a good chance of being life-supporting.
- The many-universes hypothesis: Some (rather special) part of physical reality generates multiple universes. Call this part of physical reality the universe generator. The universe generator generates many universes, with their basic physical structures (laws, constants, and initial conditions) varying at random. And since there have been or are many actual universes, it is not surprising that at least one supports life.
- Theism: The universe supports life because life fulfills certain divine purposes (or at least is a means to their fulfillment).
Zach dismisses coincidence, as it has no predictive power. One expects nothing one way or the other by suggesting that a life sustaining universe is a "coincidence." While Thomas hasn't asked for an explanation of how theism fares better than naturalism yet, Zach tosses in this diddy at the end of the letter dealing with coincidence:
Life in general, but especially conscious, intelligent life, is an extraordinary phenomenon, one that commonly evokes a sense of wonder. It is also something an intelligent being might well be interested in producing. And of course a life-supporting universe is a means of producing life. (p. 117)
Already, I predict the same general form of theistic argument: "It appears that we were given a privileged place in the universe. We are so wonderful when we contemplate ourselves that surely there is some special intent behind our existence given that we don't understand how we came to be in such an apparently improbable place!" This is an issue with intuitions. The same types of arguments plague the moral realm. "Things just seem so right and wrong -- they must be!" I'll quote from LessWrong's Eliezer Yudkowsky:
Besides, as a Bayesian, I don't believe in phenomena that are inherently confusing. Confusion exists in our models of the world, not in the world itself... I am not going to tell you that quantum mechanics is weird, bizarre, confusing, or alien. QM is counterintuitive, but that is a problem with your intuitions, not a problem with quantum mechanics. Quantum mechanics has been around for billions of years before the Sun coalesced from interstellar hydrogen. Quantum mechanics was here before you were, and if you have a problem with that, you are the one who needs to change. QM sure won't. There are no surprising facts, only models that are surprised by facts; and if a model is surprised by the facts, it is no credit to that model.
I love this quote, as it beautifully suggests that we need to stop bringing our intuitions to the table as good indicators of what we should be looking for. This applies both to the negative view on physics as well as the positive view on god. For example, as a non-believer, I find it ludicrous to suggest that "...conscious intelligent life... is also something an intelligent being might well be interested in producing." This is painting god in the human image. We find it intuitive to be enamored with ourselves and thus think that a being like ourselves, but with much greater power and knowledge, would literally find conscious life so wonderful that he/she/it would create an entire universe just to witness life on one planet amidst a sextillion of them? I just want to point out that even if our intuitions aren't satisfactorily fed concerning hypotheses 1-4 (and intuition is what I read Layman's comment above as describing concerning an intelligent being's desires), this doesn't mean that our intuitions were ever the target in the first place.
Now Layman lays out his case for theistic explanations for design:
As we've noted previously, a perfectly morally good being would be loving, and a loving being would be generous. A generous being would have reason to create entities with whom to share good things, that is, things that merit a response of wonder, admiration, and/or delight... So God would have reason to create conscious beings who can enjoy good things as well as reason to create the good things for conscious beings to enjoy. It seems especially clear that a loving God would have reason to create intelligent conscious creatures along with things for them to enjoy, such as beauty, interesting and significant activities, physical and mental pleasures, and satisfying personal relationships—for these are all of great value. (p. 118-119)
He then goes on to ask whether such beings need to be embodied (probably in response to the objection that god could have simply created heaven, inhabited with just souls/heavenly bodies, or perhaps been satisfied with the angels and called it a day). He says yes:
Yes. First, physical life is a good thing, in the sense that it merits a response of wonder, admiration, and/or delight... Second, a fine-tuned universe is a means to creating and sustaining embodied life... Third, as already noted, God would have reason to create intelligent living things capable of interesting and significant action...We can now combine the second and third points: A fine-tuned universe is both a means for producing (and sustaining) intelligent agents and a suitable stage for their actions. Therefore, since God has reason to create intelligent embodied life capable of interesting and significant action, God has reason to create a fine-tuned universe too... Fourth, if God creates life by means of a fine-tuned universe, then the creation of life carries with it at least two additional goods: (1) the aesthetic excellence of the physical universe... (2) The marvelous intricacy of the universe as a "mechanical" (i.e., nonteleological) system: I don't see how anyone can read a book on physics without coming away with a feeling that, if the universe is the product of design, it's a pure "marvel of engineering." (p. 118-120)
Long quote, I know, but it's nice to have everything we're working with out on the table. I also do this, as I think there's some serious issues going on above. I'll leave the first premise alone, but it falls into the category I mentioned above. In other words, "Gee, since I really love my physical life, clearly a good being would also think physical life is swell and therefore would create a universe that could give me just that."
I find the second reason a bit circular. It seems like one could reword it like so: "Would god create physical life? Yes, because a fine-tuned universe is just the sort of thing that god could have used to create physical life." But the whole chapter is trying to consider whether god is a good explanation for a fine-tuned universe (i.e. one that supports physical life). So he's asked whether god would create specifically physical beings and then used the unstated assumption that god, indeed, is the reason for the fine tuned universe to answer in the affirmative.
I find the fourth as a repeat of the first and third. Aesthetic pleasures seem mixed with "wonder" and "delight;" so would a fascination with the intricacy of the universe. I may be misreading the first, though. Perhaps he's stating that physical life (i.e. bodies) merit delight and wonder in themselves. But if that's the case, it would seem that we'd be delighting/taking wonder in the aesthetics and superb mechanics of their functioning... so the fourth still seems redundant.
Even having said this, I don't see why the above is unique to physical beings. Why couldn't there be spiritual analogs to "wonder, admiration, and/or delight," interesting and meaningful action, or aesthetic appreciation? The paragraph wants to validate god's intentions as a valid hypothesis to explain fine-tuning an entire universe; it seems that the reasons support non-physical existence as well, or at least provide no barrier to it. Thus god could just as well have not fine tuned and instead created some other type of reality that didn't require such fiddling.
They delve a bit into the other two non-theistic explanations above: the "percentage of possible universes" and "many universes" hypotheses. Layman isn't satisfied with these. The percentage argument states that there are many possible universes, and some percentage of them could lead to life. Thus, perhaps the actual universe that exists isn't that unlikely due to its supporting life. This is criticized because the named percentage of life supporting universes would be arbitrary. Layman says we have no way of knowing. Some don't think so. The main necessity for life supporting universes is a range of elements and energy providing stars. At least two individuals have run simulations over a range of cosmological constants to determine how likely such universes might be. Victor Stenger has the probability at about 50%, and Fred Adams has it at about 25%.1
His case against the multiverse is that we 1) don't have any evidence to support the hypothesis and that 2) it multiplies entities by number and kind. As to the first point, as far as I know, he's correct. As for the second, he says that entities are multiplied in number due to the vast increase in numbers of entities, and that the hypothesis increases the kind of universe in that they are now unobservable universes postulated in addition to the one observable one.
My understanding of Occam's razor is that it's not really a strike against the multiverse hypothesis that numerous universes are postulated because it's a single hypothesis that entails such large numbers of entities. Similarly, science didn't increase in complexity each time entities that were once thought to be irreducible (say, a substance such as water) were revealed to be made up of countless numbers of molecules, which reduced to even more atoms and even more subatomic particles. No. The theory got simpler, despite entailing the existence of these entities. One theory now explained far more than coming up with individual reasons for each "essential substance." Similarly, a hypothesis that entails a multiverse isn't having to define the reasons that every single universe exists -- physics would simply entail that this is the reality of the system.
Next, Thomas asks Zach for an explanation for god. Thomas responds that the question isn't valid because god's existence is postulated not only to explain fine tuning, but also because others have had "theistic experiences." Thus, because there are other supporting reasons for god's existence, he can't be questioned simply because he's an explanation in this case. That's all that is said about the "explanation for the explanation," and it's a shame. Regardless of what other reasons are used to support god's existence, this is one being used, and it's an argument hypothesizing that only a being such as god could have the knowledge, power, and intent to being about the precise physical constants that would eventually bring living things to inhabit the earth. A fantastic examination of this hypothesis and a response can be found in Dawkins' God Delusion as well as this wonderful summary at "Omnis affirmatio est negatio". The response is called the "Ultimate 747 Gambit."
This rebuttal beautifully ties in with a point I made earlier: we just love to use our intuitions to make assumptions. If one is to apply this fairly, we need to use our background information about knowledge, power, and intent. The only experience we have with any of these is in the physical world. If we are to extend what we think is wonderful, delightful, interesting and significant about our existence as what god would also want, we need to extend what know about the hardware and software on which these perceptions operate. The only minds we have experience with are those in brains. Power, depending on how it is defined, is inherited (strength, intelligence), learned, or designed (such as a powerful device like a piece of machinery). Intent exists only in conscious beings, and our experience with consciousness is limited to beings that are alive and have attached heads (with brains inside).
The use of god as an explanation for fine-tuning is made to look simple by asking questions like, "Well, wouldn't an all good god have great reasons for creating wonderful creature such as us?" But this entails that even if he did, he would have the intent, power, and knowledge to bring a universe into existence and pre-program it with these delicate and massively improbable physical constants. Imagine what a human would need to know or build to accomplish such a task. As this is our only frame of reference, it gets sticky to start coming up with reasons why god would not have to do such things to accomplish the same task. Simply defining god outright as powerful by definition because that's what he would have to be seems unfavorable.
In the end, I personally have no answer for the why behind our existence. In my deconversion, I bit down on some hard potential truths. I had to deal with the fact that atheism might entail a life with no "ultimate purpose," or that morality might be only what humans defined it to be by consensus and enforcement, or that I had no answer to life's "deep" questions (I haven't come to the conclusion that these actually are entailed by atheism). This is one of those issues. I am here, alive. That much I can say. If science answers the question somehow, that would be fantastic. Even if it can't, however, it doesn't mean the above constitutes a good answer. Frankly, it all seems to take the form of "Look at this conundrum! Science doesn't know how to account for it. But god, with his desires that probably want things like us to be alive does account for it. Therefore god is the best explanation!" For now, I'd rather just not know.
1 See Victor Stenger's "Is The Universe Fine-Tuned For Us?" and Fred Adams' "Stars In Other Universes: Stellar structure with different fundamental constants". The Adams article is not freely available, however the probability he finds is mentioned in Wikipedia's article on fine-tuned universes.