How to defend the fine-tuning argument just like William Lane Craig

UPDATE: Welcome visitors from Colliding Universes! Thanks for the link Denyse!

This post is the second in a two part series. In case you missed it, here is Craig’s first argument on the kalam argument.

First of all, if you’re not clear on the fine-tuning argument, click here and read Walter Bradley’s exposition of it. Dr. Walter L. Bradley (C.V. here) is the Distinguished Professor of Engineering at Baylor University. He was also a professor and department head at Texas A&M before going to Baylor. He had his Ph.D at age 24 from the University of Texas and was a tenured professor at 27.

The first argument presented by Bradley in that post is the same argument that Craig used against Hitchens in their debate. (It’s Craig’s second argument in the set of five). Bradley’s version of the argument has been presented live, in-person by Bradley at dozens of universities here and abroad, in front of students and faculty. The lecture I linked to in that post is an MP3.

The fine-tuning argument

The argument goes like this:

  1. The fine-tuning of the universe to support life is either due to law, chance or design
  2. It is not due to law or chance
  3. Therefore, the fine-tuning is due to design

What does it meaning to be fine-tuned for life?

Here are the facts on the fine-tuning:

  • Life has certain minimal requirements; long-term stable source of energy, a large number of different chemical elements, an element that can serve as a hub for joining together other elements into compounds, etc.
  • In order to meet these minimal requirements, the physical constants, (such as the gravitational constant), and the ratios between physical constants, need to be withing a narrow range of values in order to support the minimal requirements for life of any kind.
  • Slight changes to any of the physical constants, or to the rations between the constants, will result in a universe inhospitable to life.
  • The range of possible ranges over 70 orders of magnitude.
  • The constants are selected by whoever creates the universe. They are not determined by physical laws. And the extreme probabilities involved required put the fine-tuning beyond the reach of chance.
  • Although each individual selection of constants and ratios is as unlikely as any other selection, the vast majority of these possibilities do not support the minimal requirements of life of any kind. (In the same way as any hand of 5 cards that is dealt is as likely as any other, but you are overwhelmingly likely NOT to get a royal flush. In our case, a royal flush is a life-permitting universe).

Examples of finely-tuned constants

Here are a couple of examples of the fine-tuning. Craig only gave one example in the debate and didn’t explain how changes to the constant would affect the minimal requirements for life. But Bradley does explain it, and he is a professional research scientist, so he is speaking about things he worked in his polymer research lab. (He was the director)

a) The strong force: (the force that binds nucleons (= protons and neutrons) together in nucleus, by means of meson exchange)

  • if the strong force constant were 2% stronger, there would be no stable hydrogen, no long-lived stars, no hydrogen containing compounds. This is because the single proton in hydrogen would want to stick to something else so badly that there would be no hydrogen left!
  • if the strong force constant were 5% weaker, there would be no stable stars, few (if any) elements besides hydrogen. This is because you would be able to build up the nuclei of the heavier elements, which contain more than 1 proton.
  • So, whether you adjust the strong force up or down, you lose stars than can serve as long-term sources of stable energy, or you lose chemical diversity, which is necessary to make beings that can perform the minimal requirements of living beings. (see below)

b) The conversion of beryllium to carbon, and carbon to oxygen

  • Life requires carbon in order to serve as the hub for complex molecules, but it also requires oxygen in order to create water.
  • Carbon is like the hub wheel in a tinker toy set: you can bind other elements together to more complicated molecules (e.g. – “carbon-based life), but the bonds are not so tight that they can’t be broken down again later to make something else.
  • The carbon resonance level is determined by two constants: the strong force and electromagnetic force.
  • If you mess with these forces even slightly, you either lose the carbon or the oxygen.

Either way, you’ve got no life of any conceivable kind.

Is the fine-tuning real?

Yes, it’s real and it is conceded by the top-rank of atheist physicists. Let me give you a citation from the best one of all, Martin Rees. Martin Rees is an atheist and a qualified astronomer. He wrote a book called “Just Six Numbers: The Deep Forces That Shape The Universe”, (Basic Books: 2001). In it, he discusses 6 numbers that need to be fine-tuned in order to have a life-permitting universe.

Rees writes here:

These six numbers constitute a ‘recipe’ for a universe. Moreover, the outcome is sensitive to their values: if any one of them were to be ‘untuned’, there would be no stars and no life. Is this tuning just a brute fact, a coincidence? Or is it the providence of a benign Creator?

There are some atheists who deny the fine-tuning, but these atheists are in firm opposition to the progress of science. The more science has progressed, the more constants, ratios and quantities we have discovered that need to be fine-tuned. Science is going in a theistic direction. Next, let’s see how atheists try to account for the fine-tuning, on atheism.

Atheistic responses to the fine-tuning argument

There are two common responses among atheists to this argument.

The first is to speculate that there are actually an infinite number of other universes that are not fine-tuned, (i.e. – the gambler’s fallacy). All these other universes don’t support life. We just happen to be in the one universe is fine-tuned for life. The problem is that there is no way of directly observing these other universes and no independent evidence that they exist.

Here is an excerpt from an article in Discover magazine, (which is hostile to theism and Christianity).

Short of invoking a benevolent creator, many physicists see only one possible explanation: Our universe may be but one of perhaps infinitely many universes in an inconceivably vast multiverse. Most of those universes are barren, but some, like ours, have conditions suitable for life.

The idea is controversial. Critics say it doesn’t even qualify as a scientific theory because the existence of other universes cannot be proved or disproved. Advocates argue that, like it or not, the multiverse may well be the only viable non­religious explanation for what is often called the “fine-tuning problem”—the baffling observation that the laws of the universe seem custom-tailored to favor the emergence of life.

The second response by atheists is that the human observers that exist today, 14 billion years after the universe was created out of nothing, actually caused the fine-tuning. This solution would mean that although humans did not exist at the time the of the big bang, they are going to be able to reach back in time at some point in the future and manually fine-tune the universe.

Here is an excerpt from and article in the New Scientist, (which is hostile to theism and Christianity).

…maybe we should approach cosmic fine-tuning not as a problem but as a clue. Perhaps it is evidence that we somehow endow the universe with certain features by the mere act of observation… observers are creating the universe and its entire history right now. If we in some sense create the universe, it is not surprising that the universe is well suited to us.

So, there are two choices for atheists. Either an infinite number of unobservable universes that are not fine-tuned, or humans go back in time at some future point and fine-tune the beginning of the universe, billions of years in the past.

Why the fine-tuning argument matters

We need to make a decision today about how we are going to live. The evidence available today supports the fine-tuning of the universe by a supernatural mind with immense power. The progress of science has strengthened this theory against determined opposition from rival naturalistic theories.

Those are the facts, and we must all choose what to do with them.

Further study

Here is a paper by Walter L. Bradley that contains many more examples of the fine-tuning, and explanations for what happens when you change the constants, quantities and rations even slightly.

32 thoughts on “How to defend the fine-tuning argument just like William Lane Craig”

  1. Robin Collins writes the chapter for the Companion to Natural Theology on this argument.

    I believe he has a paper in which he persuasively argues that the multiverse does not solve the fine-tuning problem (and WLC often cites Roger Penrose who pointed out that we’re probably not in a multiverse)

    I believe Quodlibeta has a good number of entries where this elaborated

    While being a theist, I believe Lee Smolin got it right:
    The universe went through cosmis selection. At the end, we have one that is life-permitting.


  2. I find it odd that Christian apologists would trot out Walter Bradley, a Mechanical Engineering professor, as an alleged expert on the origins of life and the universe, which are subjects best left to cosmologists and biologists, respectively.


  3. No, I have not read the Thaxton, Bradley, and Olsen book.

    I don’t consider fine tuning to be a scientific problem. Indeed, even the philosophers are conflicted. See, for example, M. Colyvan, J. L. Garfield, and G. Priest, “Problems with the Argument from Fine Tuning,” Synthese 145 (2005) 325. From the abstract “We show that, even granting fine tuning of the universe, it does not follow that the universe is improbable, thus no explanation of fine tuning, theistic or otherwise, is required.” Another interesting article is B. Monton, “God, Fine-Tuning, and the Problem of Old Evidence,” Brit. J. Phi. Sci. 57 (2006), 405. Monton, by contrast, finds that “the theistic fine-tuning argument is a powerful argument.” Nevertheless, he concludes that “it is reasonable to hold that the fine-tuning evidence does not provide evidence for the existence of God.” Some philosophers do find the fine-tuning argument to be compelling. However, they generally are theists to begin with.


  4. Well, that’s funny because the argument from fine-tuning is pretty much the only probablistic argument that makes any sense.
    Once we reject this one, the probablistic argument from evil has to be thrown out as well.


  5. If you’ll forgive the plug, I offer some additional insight into William Lane Craig’s debating style on my blog. I agree that he certainly mopped the floor with Hitchens; Craig is very, very good at what he does.

    I do think there is a significant structural problem with the fine-tuning argument in that premise 1 is asserted rather than proven, which (I think) dovetails with what Sam Meyerson is saying.


  6. I received the following e-mail from Dr. Michael G. Strauss, an experimental particle physicist, regarding the speculations on QM and the chaotic inflationary model.

    Wintery Knight,

    Quantum mechanics works within the laws of physics. So if you postulate that this universe was created from QM then you must also postulate that a previous universe with similar laws existed previously.

    There are a number of theories that would allow multiple universes, though none have any experimental verification. Have you read Jeff’s “Who’s Afraid of a Multiverse?” It is very good.


    Mike is very big on experimental evidence for theories, because that’s what he does all day as an experimental particle physicist.

    Speculating about quantum mechanics or chaotic inflationary models requires you to go beyond the experimental evidence to the positing of unobservable realities.

    In contrast with theoretical speculations, I listed multiple lines of evidence in favor of the fine-tuning of physical constants, quantities and ratios, and that has been confirmed by multiple converging discoveries.


  7. Very powerful argument indeed! Food for thought!

    I just had a sounding idea!

    I mean, if abstract entities like numbers or consciences can exist outside of this space-time reality it could mean that mathematics is independent from God! It doesn’t need a cause and exists forever because it’s outside of time!

    In essence it could be a “pre-existing” or “same time existing” tool that God use to create this reality for example!


  8. According to wikipedia, Martin Rees is an Anglican, not an atheist – though I’m not familiar with his religious stance in detail.


    1. Wikipedia is wrong. Rees is an atheist who attends Anglican church occasionally.

      Consider this passage from Richard Dawkin’s “The God Delusion”

      The present Astronomer Royal and President of the Royal Society, Martin Rees, told me that he goes to church as an ‘unbelieving Anglican … out of loyalty to the tribe’. He has no theistic beliefs, but shares the poetic naturalism that the cosmos provokes in the other scientists I have mentioned.

      You can read the whole chapter at the New York Times


  9. Hey, atheist here. Just astounded by your characterisation of the atheist’s response. I’ve never heard any atheist use the argument that humans caused the fine tuning. It doesn’t make sense because humans would still have to exist in some now corrupted timeline where the universe wasn’t fine-tuned.

    I have a whole post on my blog dedicated to this topic but I’ll summarise my main arguments.

    1. Possibility of a multiverse.
    2. Possibility of an oscillating universe

    3. The Vast (to use Dennett’s terminology) majority of the universe does not contain life, so to claim that life is its purpose is merely superimposing your own subjective judgement onto it.

    4. Related to 3. Clearly the universe is fine-tuned to make hydrogen, since that is the most abundant substance in the universe. Life seems to be fairly far down in the priorities of the universe. Of course I’m (half) joking, but there is no reason why one natural phenomenon needs a fine tuner any more than any other.

    5. The argument flauts its own premises by posing the existence of a creator which doesn’t need a fine-tuned universe. So either the premise is wrong, or we have an infinite regress of fine-tuners.

    6. We have no idea if these constants are even capable of changing. To state that they have been fine tuned without this information is nothing more than speculation.

    7. It could be that the state of the universe is unlikely, but not as unlikely as the existence of a fine-tuner. In this case it would just be a big coincidence.

    8. Even if the fine-tuning argument were valid, it says nothing about the type of creator that exists, so to go from this deist creator to the Christian God is a huge leap.

    Maybe you can integrate these arguments into your post and address them, instead of a straw man?



    1. Thanks for your comment. You’ll note that in my piece I cited numerous scientific facts and produced an argument that was logically valid. Now let’s take a look at what you wrote.

      1) This is a speculation with no scientific evidence. Notice how I appeal to an experimental particle physicist for my conclusion.

      2) This has been disproved theoretically and observationally. Notice how I cite research papers that do not merely speculate, but are based on observations.

      3) This is speculation about God’s motives. You are not in a position to dictate to God how he would have accomplished his goals. If you would like to listen to William Lane Craig speak on these scientific arguments, and listen to Dennett’s LAME response, click here.

      4) This is speculation about God’s motives. You can feel free to joke about the evidence for and against God. I don’t joke about these issues – I prefer to cite evidence.

      5) Fine-tuning is an example of intelligent design such that a selection from a field of possibilities corresponds to an independently specified pattern. I.e. – the subset of functional proteins compared to the set of possible sequences of amino acids. God is not composed of parts so is not fine-tuned.

      6) This is more speculation. Don’t make arguments based on what “we” don’t know. I make arguments based on what we do know. You do the same.

      7) “It could be…” It could be that monkeys will fly out of my butt. Stop speculating about things we cannot know. Let’s see your argument, and the peer-reviewed data to back it up. This is not a game.

      8) The argument is not meant to prove the Christian God.The argument, taken together with a bunch of other scientific arguments, is meant to prove a Creator and Designer of the universe. To prove Christian theism, you make a case for the resurrection and then debate it in public in the university. And then you respond to philosophical objections, such as evil, suffering and the hiddenness of God.


  10. I don’t have an awful lot of time, I’ve got a degree to do, but just to point out a couple of things.

    Only two of my points were based on science, the rest are philosophical arguments which do not require peer-reviewed papers, so you can stop trying to make out that my arguments are unsupported. I’ll concede you on point two, but it doesn’t matter, it’s very much related to point one. There is growing excitement in theoretical physics about bubbles in spacetime. We’ve known about these since the 1960’s but now it seems that at the Planck length scale, bubbles can break off. This explains why the universe is not regular, which you would expect from an ultimate beginning, and also provides justification for the multiverse theory. Like I say I don’t have time to trawl the internet looking for the paper, but it doesn’t matter, it wasn’t my main point, I was just pointing out that it’s possible.

    “This is speculation about God’s motives” Wow. The irony. The whole point was to demonstrate that you are imposing your judgement of what’s important (life) onto the origins of the universe. It misses the point spectacularly to say what you did. Yes, I am speculating, but the point was that so are you, and your speculation is much bigger since life is only found on one planet out in the sticks of a little galaxy, and you think it’s the purpose of the universe.

    Everywhere where you’ve said “that’s speculation” (especially in number 6), that’s exactly my point, and you missed it. You’re saying the constants are fine-tuned, we don’t even know if they can change! So please, “Don’t make arguments based on what ‘we’ don’t know.”


    1. “There is growing excitement”. That is not an argument.
      “I was just pointing out what’s possible”. I want an argument, and some evidence, not a speculation.

      The constants cannot change, that’s why they are called “constants”. This is the way physicists refer to them in the literature. Once they are set, they are set, like the laws of nature are set. That is why when you open a physics textbook, you use those numbers in calculations in order to do science. We have never found a case where the constants have changed. You are questioning the very foundation of science, and you cannot produce any evidence.

      If you make a claim like “the constants can change”, which contradicts what every scientist believes about the constants, then you bear the burden of proof. Speculation is not an argument. When I argue, I use deductive arguments with premises more plausible than not. We know that constants cannot change because we have never observed to change. If you are claiming differently from our common experience, you bear the burden of proof.

      I think we’ve gone far enough with this.


  11. Hey there again WK- I was looking through loads of articles at once a few days ago and I remember seeing something under a “further study” section about a small podcast, maybe 15 mins, which you linked to and it was a summary/introduction of intelligent design or the fine tuning argument. Do you know where it is? If not any good short introductions to intelligent design arguments that I can send to my Christian friend?
    Thanks in advance =)


  12. I’m a theist, however, I am interested in how you’d respond to objections by Atheists to the fine-tuning argument such as:

    Pointing to parts of the universe which don’t seem fine-tuned for life (black holes, the fact that stars will explode) etc.




      1. That makes sense. Thanks for the response. I suppose those arguments (i.e. pointing to parts not habitable) misunderstand the premise of the fine-tuning argument.


  13. Doesn’t the fine-tuning argument only work if it assumes that life was the goal or purpose of the universe. I like the metaphor Lee Strobel gave because it helps me explain my point. If we let the constants be represented by say, 50 dials. If I randomly spun all the dials the odds of me landing on a set of numbers is 1 in 1. However whichever set of numbers I land on I could look at that set and say the odds of me landing on this specific set is 1 in 10^x (x representing some very large number).

    So the fact that we landed on an improbable set of values isn’t really significant at all. The only claim that makes it significant is to say that ours is one of the few that is life permitting, and therefore must of have been fine-tuned. The problem is there’s no basis to make the claim that life is significant or has a purpose. There must be so many things that could only occur in a very small number of universes, yet ours isn’t one of them as we didn’t land on that set of constants.

    The article has an example of cards, demonstrating that a Royal Flush may be as likely as any specific set of cards, however due to the far greater number of non-Royal Flush hands, the odds of getting a Royal Flush are still very very small. The also demonstrates my point, as this example PROVIDES a set goal, while the example of the universe does not. I mean the odds of getting a Royal flush are the same as getting a straight flush involving cards 2-6, yet in Poker there is a distinction made that a Royal Flush is the goal. However what’s the basis that a life-permitting universe is the goal as oppose to a life-prohibiting one?


    1. Tim:

      I think the level of fine tuning being referred to here would require an analogy more like you getting a royal flush every time you sat down to play cards.

      Now I would think myself very lucky to get a royal flush and win big during a game of cards.

      But if I was delt a royal flush everytime I played I would begin to suspect that something more than mere chance was at play here wouldnt you?


  14. You (or WLC) state the three options: chance, design, or law, and then assert that the universal constants “are not determined by physical laws.”

    I am curious how you know this.

    Clearly we are not talking about the physical laws that exist within our universe – those laws don’t (seem to) create universes. We are talking about hypothetical laws (lets call them creation-laws) which govern the creation-event of universe(s), including the creation of space-time, the assignment of physical laws to those universes, and the assignment of values to their physical constants. I’d love to know what evidence you have that no such creation-laws exist.

    Also (minor point) I’m curious where you get your ‘range of 70 orders of magnitude’ from. How do you know that the universal constants may not range from plus-infinity to minus-infinity, and are limited to these ranges? Surely to know this, you would have to have knowledge of these non-existant ‘creation-laws’? Or be told, by the creator?

    Thank you.


    1. Creation Laws?
      You dont seem to know what a Law actually is.
      Laws dont create anything. Do the Laws of Motion actually Move anything or must some other thing ACT on it? Laws just describe what is already happening. To put the word Creation in there is nonsensical.

      Where does this hypothetical law exist? Is it just floating around in the nothingness? Laws dont have Agent causality—in short-they dont exists–they are not entities–they have no being–they simply describe what we observe. They dont create themselves or anything else.

      I know some people are afraid of there being a Creator but its been *The explanation of creation, in every culture throughout human history, for a reason. Just because there are biased people who dont want there to be a God grasping at straws to avoid the obvious, coming up with Infinite universe makers that create *Everything is never gonna change that. Their explanations are to the point now that they are just embarrassing.


      1. Thank you for your response. However, I think you’ve missed my point.
        My question was:
        You […] state that there are three options to explain how the universal constants acquired their values:chance, design & laws, and then you dismiss one of those options (laws) as not possible.
        I want to know why you dismiss it as ‘not possible’.

        “Laws just describe what is happening”. Exactly. And these hypothetical laws would describe what happens during the creation of a universe.
        How can you assert that either:
        a. there weren’t any laws which ‘described what was happening’ as our universe was created, or
        b. that the laws which ‘described what was happening’ during the creation of our universe didn’t describe how the constants got their values ?

        Nobody is claiming that the laws actually did the creating. Neither me, nor WLC. These are (hypothetical) laws which ‘describe the constraints on the possible values of constants when a universe is created.

        I used the phrase ‘creation laws’ to refer to the particular (hypothetical) laws which describe how universes are created, and to distinguish them from any other laws. Feel free to ignore this phrase if you find it too confusing – it doesn’t affect my question


        1. Mk, this one is easy. Laws are descriptions of material objects. At the beginning of the universe, there was no material, so there were no laws. Laws don’t cause anything, there are just mathematical descriptions of how physical objects behave. If the thing to be explained is a baseball game, then a box score in the newspaper doesn’t explain the even, it describes it. The baseball game itself is caused by agents.


  15. WK,
    thank you for your response.

    “Laws are descriptions of material objects.”
    No, they aren’t.
    From, 12a seems most appropriate:
    “A statement describing a relationship observed to be invariable between or among phenomena for all cases in which the specified conditions are met: the law of gravity.”

    your previous ‘definition’ was better:
    “Laws just describe what is happening”.

    So my question is: how can you assert that there weren’t any ‘laws’ which describe the ‘relationship between the phenomena’ manifest during the creation of the universe. Even if these ‘phenomena’ were the phenomena which involved the creation of material.

    I am not asserting that there were such laws. I just don’t understand how you can assert that there were not.

    Also: “At the beginning of the universe, there was no material”

    AFAIK, we have no information about what exists, or does not exist, before or beyond our universe. How do you know that material didn’t exist outside of our universe, or before it’s beginning? How do you know that the beginning of our universe wasn’t a re-arrangement of pre-existing matter, energy, space, time, or even something else more exotic?

    Granted – words like ‘outside’ or ‘before’ aren’t quite right when we are talking about non-linear and non-continuous time or space – but I lack more appropriate vocabulary, and I’m sure you know what I mean.

    “Laws don’t cause anything”. No, they don’t. You seem to be hung up on this. If I gave the impression that I believe that laws are direct causal agents – then please ignore that bit, because it was not my intended meaning.


  16. I rather enjoyed your quote here:

    “The problem is that there is no way of directly observing these other universes and no independent evidence that they exist.”

    The irony here is that you could easily say the exact same thing about God. There is no way of directly observing God, and no independent evidence of His existence; just a bunch of arguments. It’s just an unsubstantiated assertion being thrown in to explain some deep cosmic mystery. Therefore, by your own logic, we must discard the God hypothesis as well.

    Christian apologetics as its finest, folks.


      1. But inference to the best explanation no longer works if there is a second, equally good explanation is possible, namely, the multiverse hypothesis. Moreover, the latter doesn’t require us to posit the existence of new types of entities. We already know there was one big bang, so for all we know there could have been more & admitting of more would do nothing to disrupt our current understanding of this universe. In the case of God the case is quite different. In the latter case, it’s not merely that God is not verifiable, but that God is something so completely different from all the stuff that is verifiable. Moreover, the existence of God has been used as an an explanatory cog so many times in the past and turned out to be scientifically unnecessary, that we would have to be fools to fall for that trick again in the absence of really, really good evidence. (I’m a Christian theist by the way. I just don’t see how this particular argument can possibly withstand the multiverse hypothesis. So I’m with James on this one.)


  17. The BGV Theorem pinpoints the need for a beginning of all physical universe. The BGV theorem is especially helpful in noting that not only does our universe require a beginning point, but all physical universes require a singularity. Any physical universe including the theoretical multiverse must have an initial starting point. Thus, while it could be that a multiverse exists, a multiverse does not get around the need for a starting point which leads to the third point that needs to be considered.

    Whatever begins to exist has a cause…since the universe (or universes) including all space, energy, matter and time began to exist there must be a cause outside of space, energy, matter and time. For many this would cause would be a Creator.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s