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Does a commitment to naturalism undermine rational thought and textual meaning?

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Dr. William Lane Craig had a formal debate with an atheist philosopher named Alex Rosenberg a few months back that brought up an interesting idea. Rosenberg is a strong naturalist and he suggests all kinds of counterintuitive outworkings of naturalism in his book. Dr. Craig brought up a bunch of those strange views in his debate, and I listed them out in my summary of the debate as follows:

  1. The argument from the intentionality (aboutness) of mental states implies non-physical minds (dualism), which is incompatible with naturalism
  2. The existence of meaning in language is incompatible with naturalism, Rosenberg even says that all the sentences in his own book are meaningless
  3. The existence of truth is incompatible with naturalism
  4. The argument from moral praise and blame is incompatible with naturalism
  5. Libertarian freedom (free will) is incompatible with naturalism
  6. Purpose is incompatible with naturalism
  7. The enduring concept of self is incompatible with naturalism
  8. The experience of first-person subjectivity (“I”) is incompatible with naturalism

We are concerned with #1 and #2 in this post.

Now I was visiting my parents last week in my home town and Dad and I went to church on Sunday. He wanted to listen to some weird sing-song-voiced pastor on the drive there, but I plugged in my smartphone and we listened to these three podcasts by William Lane Craig instead.

Dr. Craig was explaining in part 3 (I think) about how he went on the offensive with the 8 points, and Dad asked me why Dr. Rosenberg wrote that if naturalism is true, then nothing written down is meaningful. He also wanted to know why Dr. Rosenberg would write a book if his worldview entailed that nothing written down is meaningful.

The solution has to do with Rosenberg’s denial of “intentionality”, which is the idea that something can be about something else. For example, I can think about what I had for breakfast today on the way to church (two apples and coffee) or I can think about the sermon today in my home church and how good it was. A naturalist believes that the whole universe is made up of pure matter alone, and matter cannot be about anything. So Rosenberg denies this common sense view of “intentionality” or “aboutness” because there is no room for it on his naturalistic / materialistic / physicalist view of reality.

Here is a post by Bill Valicella on Maverick Philosopher blog that answers Dad’s questions.

First, Rosenberg’s own view from his book.

A single still photograph doesn’t convey movement the way a motion picture does. Watching a sequence of slightly different photos one photo per hour, or per minute, or even one every 6 seconds won’t do it either. But looking at the right sequence of still pictures succeeding each other every one-twentieth of a second produces the illusion that the images in each still photo are moving. Increasing the rate enhances the illusion, though beyond a certain rate the illusion gets no better for creatures like us. But it’s still an illusion. There is noting to it but the succession of still pictures. That’s how movies perpetrate their illusion. The large set of still pictures is organized together in a way that produces in creatures like us the illusion that the images are moving. In creatures with different brains and eyes, ones that work faster, the trick might not work. In ones that work slower, changing the still pictures at the rate of one every hour (as in time-lapse photography) could work. But there is no movement of any of the images in any of the pictures, nor does anything move from one photo onto the next. Of course, the projector is moving, and the photons are moving, and the actors were moving. But all the movement that the movie watcher detects is in the eye of the beholder. That is why the movement is illusory.

The notion that thoughts are about stuff is illusory in roughly the same way. Think of each input/output neural circuit as a single still photo. Now, put together a huge number of input/output circuits in the right way. None of them is about anything; each is just an input/output circuit firing or not. But when they act together, they “project” the illusion that there are thoughts about stuff. They do that through the behavior and the conscious experience (if any) that they produce. (Alex Rosenberg,The Atheists’ Guide to Reality: Enjoying Life Without Illusions.  The quotation was copied from here.)

And here is what Bill says about that:

Rosenberg is not saying, as an emergentist might, that the synergy of sufficiently many neural circuits gives rise to genuine object-directed thoughts.    He is saying something far worse, something literally nonsensical, namely, that the object-directed thought that thoughts are object-directed is an illusion.  The absurdity of Rosenberg’s position can be seen as follows.

  1. Either the words “The notion that thoughts are about stuff is illusory”  express a thought — the thought that there are no object-directed thoughts — or they do not.
  2. If the latter, then the words are meaningless.
  3. If the former, then the thought is either true or false.
  4. If the thought is true, then there there are no object-directed thoughts, including the one expressed by Rosenberg’s words, and so his words are once again meaningless.
  5. If the thought is false, then there are object-directed thoughts, and Rosenberg’s claim is false.

Therefore:

  • Rosenberg’s claim is either meaningless or false.  His position is self-refuting.

As for the analogy, it is perfectly hopeless, presupposing as it does genuine intrinsic intentionality.  If I am watching a movie of a man running, then I am under an illusion in that there is nothing moving on the movie screen: there is just a series of stills. But the experience I am undergoing is a perfectly good experience that exhibits genuine intrinsic intentionality: it is a visual experiencing of a man running, or to be perfectly punctilious about it: a visual experiencing AS OF a man running.  Whether or not the man depicted exists, as would be the case if the movie were a newsreel, the experience exists, and so cannot be illusory.

To understand the analogy one must understand that there are intentional experiences, experiences that take an accusative.  But if you understand that, then you ought to be able to understand that the analogy cannot be used to render intelligible how it might that it is illusory that there are intentional experiences.

What alone remains of interest here is how a seemingly intelligent fellow could adopt a position so manifestly absurd.  I suspect the answer is that he has stupefied himself  by  his blind adherence to scientistic/naturalistic ideology.

If you want to sort of double check the details, then go ahead and watch the debate or read my summary or listen to the debate audio, and then listen to Dr. Craig’s three podcasts that I linked above.

I know a lot of you are thinking right now “Hey! You cheater! That’s a presuppositional argument! You said they were bad!” Well, I didn’t say they were bad, I said that the epistemological view of presuppositionalism was bad. Presuppositional arguments are good. See below for a few posts about them. Use them all you can, but use the good scientific and historical evidence, too.

Positive arguments for Christian theism

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William Lane Craig debates Victor Stenger: Does God Exist?

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This debate took place on March 1, 2010 at Oregon State University.

In this debate, Victor Stenger does affirm his belief that the universe could be eternal in his second rebuttal (1:02:30), thus denying the standard Big Bang cosmology. He also denies the law of conservation of energy and asserts that something can come from nothing in his concluding speech (1:33:50). He also caused the audience to start laughing when he said that Jesus was not moral and supported slavery. There is almost no snark in this summary. Instead, I quoted Dr. Stenger verbatim in many places. I still think that it is very entertaining even without the snarky paraphrasing.

The debate includes 30 minutes of Q&A with the students.

Here is the MP3 file for the audio.

Here’s the video of the debate:

Dr. Craig’s opening speech:

  • The ontological argument
  • The contingency argument
  • The cosmological argument
  • The moral argument
  • The resurrection of Jesus (3-fact version)
  • Religious experience

Dr. Stenger’s opening speech:

  • There is no scientific evidence for God’s existence in the textbooks
  • There is no scientific evidence for God acting in the universe
  • God doesn’t talk to people and tell them things they couldn’t possibly know
  • The Bible says that the Earth is flat, etc.
  • There is no scientific evidence that God answers prayers
  • God doesn’t exist because people who believe in him are ignorant
  • Human life is not optimally designed and appears to be the result of a blind, ad hoc evolutionary process
  • The beginning of the universe is not ordered (low entropy) but random and chaotic
  • It’s theoretically possible that quantum tunneling explains the origin of the universe
  • The laws of physics are not objectively real, they are “our inventions”
  • Regarding the beginning of the universe, the explanation is that something came from nothing*
  • Nothing* isn’t really nothing, it is “the total chaos that we project existed just before the big bang”
  • If something has no structure, then “it is as much nothing as nothing can be”
  • Consciousness is explainable solely on the basis of material processes
  • There are well-informed, rational non-believers in the world and God would not allow that

Dr. Craig’s first rebuttal:

Stenger’s argument that there is no objective evidence for God’s existence:

  • First, it is not required that God rely only on objective evidence in order to draw people to himself (Alvin Plantinga)
  • Second, God is not required to provide evidence to everyone, only to the people who he knows would respond to him
  • Third, Craig gave lots of objective evidence, from science, history and philosophy
  • Stenger asks for certain evidence (answered prayers, prophecy, etc.), but Craig presented the evidence we have

Stenger’s argument that the balance of energy is zero so “nothing” exists:

  • if you have the same amount of assets and liabilities, it doesn’t mean that nothing exists – your assets and liabilities exist
  • Christopher Isham says that there needs to be a cause to create the positive and negative energy even if they balance
  • the quantum gravity model contradicts observations
  • the vacuum is not the same as nothing, it contains energy and matter
  • the BVG theorem proves that any universe that is expanding must have a beginning

Stenger’s argument that mental operations can be reduced to physical operations:

  • mental properties are not reducible to physical properties
  • epiphenomenalism: is incompatible with self-identity over time
  • epiphenomenalism: is incompatible with thoughts about other things
  • epiphenomenalism: is incompatible with free will
  • substance dualism (mind/body dualism) is a better explanation for our mental experience
  • God is a soul without a body
Dr. Stenger’s first rebuttal:

Craig’s cosmological argument:

  • Craig’s premise is “everything has a cause”, but quantum mechanics has causeless events
  • There are speculative theories about how something could have come into being uncaused out of nothing
  • “I don’t know of a single working cosmologist today who believes there was a singularity prior to the Big Bang”
  • “If there wasn’t a singularity then there’s no basis for arguing that time began at that point”
  • “There’s no reason from cosmology that we know of that the universe can’t be eternal”
  • “When I talk about an eternal universe, I mean a universe that has no beginning or end”
  • The Hartle-Hawking model doesn’t have a beginning
  • “There was no violation of energy conservation by having a universe coming from nothing”
  • “The universe could have come from a previous universe for example or even just from a region of chaos”
  • The paper by Vilenkin is counteracted by other papers (he doesn’t specify which ones)

Craig’s moral argument:

  • Dr. Craig is arguing from ignorance
  • But morality can be decided by humanity just like governments pass laws, and that’s objective
  • Dr. Craig has too little respect for the human intellect
  • I don’t need to tell me that slavery is wrong
  • The Bible supports slavery
  • Atheists can behave as good as theists
  • Morality just evolved naturally as an aid to survival

Craig’s resurrection argument:

  • No Roman historians wrote about the execution of Jesus but none of them did
  • The empty tomb is doubtful because it is only mentioned in the gospels, not by Paul
  • John Dominic Crossan says there was no empty tomb
  • Christianity only survived because the Roman empire thought that they were useful

Dr. Craig’s second rebuttal:

Craig’s cosmological argument:

  • There is no reason to prefer an indeterministic interpretation of quantum mechanics
  • Dr. Stenger himself wrote that deterministic interpretations of quantum mechanics are possible
  • The vacuum in quantum mechanics is not nothing
  • The quantum vacuum he proposes cannot be eternal
  • The cosmological argument does not require a singularity
  • The Hartle-Hawking model is from 1983
  • Hawking says that there is a beginning of space and time after that model
  • The Hartle-Hawking model does still have a beginning of time – the model is not eternal
  • The BVG theorem that requires a beginning for expanding universes is widely accepted among cosmologists

Craig’s moral argument:

  • Stenger redefined objective to mean that most people agree with it – but that’s not what objective means
  • Objective means right and wrong whether anyone accepts it or not
  • Richard Dawkins himself says that on atheism there is “no evil and no good” – why is he wrong?
  • Even Dr. Stenger says that morality is the same as passing laws – it’s arbitrary and varies by time and place
  • But on his view, right and wrong are the same as deciding which side of the road to drive on
  • But somethings really are right and some things are really wrong

Craig’s resurrection argument:

  • Josephus is a Roman historian and he wrote about Jesus, for example
  • There were four biographies of Jesus are the best sources for his life
  • The scholars that Stenger mentioned are on the radical fringe

Dr. Stenger’s second rebuttal:

Knowledge and the burden of proof:

  • Dr. Craig has to bear the burden of proof, not me – because his claim is more “extravagant”
  • “I don’t have to prove that a God was not necessary to create the universe”
  • “I don’t have to prove that a God did not design the universe and life”
  • “I don’t have to prove that the universe did not have a beginning”
  • “I don’t have to prove that God did not provide us with our moral sense”
  • There are a lot of books written about how morality evolved naturally
  • “I don’t have to prove that the events surrounding the supposed resurrection of Jesus did not take place”
  • Bart Ehrman says that the gospels are generally unreliable (Note: Ehrman accepts all 3 of Craig’s minimal facts)
  • Just because people are willing to die for a cause, does not make their leader God, e.g. – the Emperor of Japan

Aesthetic concerns about the universe:

  • I don’t like dark matter and I wouldn’t have made the universe with dark matter
  • I don’t like the doctrine of penal substitution
  • I don’t like the doctrine of original sin
  • I don’t like the heat death of the universe

Dr. Craig’s conclusion:

The case for atheism:

  • Dr. Stenger had two arguments and he has to support his premises
  • Dr. Craig addressed his two arguments and each premise and Dr. Stenger never came back on it

The contingency argument:

  • Dr. Stenger has dropped the refutation of this argument

The cosmological argument:

  • The theoretical vacuum he proposes cannot be eternal

The moral argument:

  • He asserts that things are wrong, but there is no grounding for that to be objective on atheism

The resurrection of Jesus:

  • There are surveys of scholars on the empty tomb and 75% of them agree with it
  • Bart Ehrman agrees with all 3 of the minimal facts that Dr. Craig presented
  • Ehrman’s objection to the resurrection is not historical: he’s an atheist – he thinks miracles are impossible

Religious experience:

  • No response from Dr. Stenger

Dr. Stenger’s conclusion

The cosmological argument:

  • “I argued that we have very good physical reasons to understand how something can come from nothing”
  • “There is a natural tendency in the universe… to go from.. simpler thing to the more complicated thing”
  • The transition from a vapor to a liquid to ice shows how something could come from nothing
  • “It cannot be proven that the universe had a beginning”

The moral argument:

  • Objective morality, which is independent of what people think, could be developed based on what people think
  • “Jesus himself was not a tremendously moral person… he had no particular regard for the poor… he certainly supported slavery… he was for the subjugation of women” (audience laughter)

The resurrection argument:

  • Bart Ehrman says that the majority of the gospels are unreliable

Religious experience:

  • I don’t see any evidence that there is anything more to religious experience than just stuff in their heads

God’s purpose of the world should be to make people feel happy:

  • God could have made people feel happier
  • God could have made people not die
  • God could could have made the universe smaller: it’s too big
  • God could have made it possible for humans to live anywhere “even in space”
News

William Lane Craig posts full Vilenkin e-mail misrepresented by Krauss in their debate

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First, Dr. Craig posted the e-mail from Vilenkin to Krauss, which Krauss used in his debate with Craig, with the parts Krauss omitted in bold:

Hi Lawrence,

Any theorem is only as good as its assumptions. The BGV theorem says that if the universe is on average expanding along a given worldline, this worldline cannot be infinite to the past.

A possible loophole is that there might be an epoch of contraction prior to the expansion. Models of this sort have been discussed by Aguirre & Gratton and by Carroll & Chen. They had to assume though that the minimum of entropy was reached at the bounce and offered no mechanism to enforce this condition. It seems to me that it is essentially equivalent to a beginning.

On the other hand, Jaume Garriga and I are now exploring a picture of the multiverse where the BGV theorem may not apply. In bubbles of negative vacuum energy, expansion is followed by cocntraction, and it is usually assumed that this ends in a big crunch singularity. However, it is conceivable (and many people think likely) that singularities will be resolved in the theory of quantum gravity, so the internal collapse of the bubbles will be followed by an expansion. In this scenario, a typical worldline will go through a succession of expanding and contracting regions, and it is not at all clear that the BGV assumption (expansion on average) will be satisfied.

I suspect that the theorem can be extended to this case, maybe with some additional assumptions. But of course there is no such thing as absolute certainty in science, especially in matters like the creation of the universe. Note for example that the BGV theorem uses a classical picture of spacetime. In the regime where gravity becomes essentially quantum, we may not even know the right questions to ask.

Alex

Now recall that Krauss excuses the selective editing of the e-mail in the debate by saying that it was “too technical” to include. Judge for yourself if the omitted lines are “too technical” or whether they were omitted in order to mislead people about the evidence for the beginning of the universe.

Dr. Craig comments:

Whoa! That puts a very different face on the matter, doesn’t it? Why didn’t Krauss read the sentence, “It seems to me that it is essentially equivalent to a beginning”? Because it was too technical? Is this the transparency, honesty, and forthrightness that Krauss extols? (By the way, Vilenkin’s criticism of these models is the same one that Vilenkin makes in his Cambridge paper: far from showing an eternal past, these models actually feature a universe with a common beginning point for two arrows of time.)

And why did Krauss delete Vilenkin’s caveat that the BGV theorem can, in his estimation, be extended to cover the case of an expanding and contracting model such as Garriga and Vilenkin are exploring? And why delete the remark that such a model is usually assumed to be incorrect? It’s evident that Vilenkin’s email was selectively edited to give it the spin Krauss wanted.

Some people told me that they thought that Dr. Craig needed to be a little less gracious with Krauss in the debate, but that comment takes Krauss on directly. Too bad most of the people who watch the debate will never know unless they see the original e-mail from Vilenkin that Craig posted.

Dr. Craig then wrote to Dr. Vilenkin about this misrepresentation and here is part of the reply:

The Aguirre-Gratton model can avoide singularities by postulating a small “initial” closed universe and then allowing it to evolve in both directions of time. I put “initial” in quotation marks, because Aguirre and Gratton do not think of it that way. But this model requires that a very special condition is enforced at some moment in the history of the universe. At that moment, the universe should be very small and have very low entropy. Aguirre and Gratton do not specify a physical mechanism that could enforce such a condition.

Carroll and Chen claim that the universe did not have to be small at that special moment. But in my recent paper I show that in this case singularities are unavoidable.

[…]I think you represented what I wrote about the BGV theorem in my papers and to you personally very accurately.

Now I don’t want anyone to get the idea that all atheists are like Krauss. I distinctly remember another atheist named Anthony Flew debating Dr. Craig and a questioner from the audience asked him why not prefer speculative cosmologies like the eternally oscillating model. Dr. Flew (unlike Dr. Krauss) was honest – he said that we have to accept the science we have today based on the evidence we have today. Dr. Krauss is not willing to accept the science we have today and the evidence we have today. That’s the difference. This is a failing of Dr. Krauss’ will and intellect. He simply cannot bring himself to accept what science has shown, if it impacts his autonomy in any way. He would rather mislead himself and others with speculations rather than face reality.

Watch the whole debate – see for yourself

I’ll re-state the relevant part of my Craig-Krauss debate summary below. The summary has the full video.

The segment from 52:18 to 57:12 about the Vilenkin e-mail on the BVG theorem is a must-see. Krauss is standing up and gesticulating while Craig is calmly trying to quote a paper by Vilenkin that shows that Krauss is misrepresenting Vilenkin. Krauss constantly interrupts him. After a while, when Craig exposes him as having misrepresented Vilenkin and gets him to admit that all current eternal models of the universe are probably wrong, he quietens down and can’t even look at Craig in the face.

Cosmological argument:

  • Craig: The e-mail says any universe that is expanding, on average, requires a beginning
  • Craig: There are two models – Aguirre & Gratton and Carroll & Chen – where there is a period of contraction before the expansion
  • Craig: The two models are the ones cited in the e-mail that Dr. Krauss showed
  • Craig: In the very paper by Vilenkin that I cited, he says that both of those models don’t work
  • Krauss: (agitated and interrupting) Vilenkin said that they have to make an assumption about entropy that they have no rationale for
  • (as Craig starts to talk Krauss makes an exaggerated, disrespectful gesture and sits down in a huff)
  • Craig: Yes, an unwarranted assumption means that they don’t have EVIDENCE for their theories being correct
  • Krauss: (agitated and interrupting) “All the evidence suggests that the universe had a beginning but WE DON’T KNOW!!!!!!!” (raising his voice)
  • Craig: I’m not saying that we know that the universe had a beginning with certainty
  • Craig: I am saying that the beginning of the universe is more probably true than false based on the evidence we have
  • Craig: And you  agree with me about that – you think the universe had a beginning
  • Krauss: (agitated and interrupting) (Unintelligible)
  • Moderator: One at a time
  • Craig: In your Vilenkin e-mail slide, at the end of the paragraph where the two models are mentioned that Vilenkin specifically shows…
  • (I am guessing that Craig is going to ask why so much of what Vilenkin wrote has been cut out of the e-mail that Krauss showed)
  • Krauss: (agitated and interrupting) Because it was technical…
  • Moderator: Lawrence! Hang on a sec!
  • Craig: He specifically shows that these models are not past eternal, and that they require a beginning just like the others…
  • Krauss: (agitated and interrupting) We can do the math if you want
  • Craig: Now wait. I couldn’t help notice that there on your slide there was a series of ellipsis points indicating missing text…
  • Krauss: (agitated and interrupting) “Yeah, because it was technical!”
  • Craig: “I wonder what you deleted from the original letter”
  • Krauss: (agitated and interrupting) “I just told you!”
  • Craig: “Now wait. Could it have been something like this:  (reads a quote from Vilenkin) ‘You can evade the theorem by postulating that the universe was contracting prior to some time. This sounds as if there is nothing wrong with having contraction prior to expansion. But the problem is that a contracting universe is highly unstable. Small perturbations would cause it to develop all sorts of messy singularities, so it would never make it to the expanding phase.’
  • Craig: “That’s Vilenkin.”
  • Krauss: “In this paper, that’s absolutely right”
  • Krauss: But it’s ok for theories to assume things that we know are wrong – they are still good theories – it’s unknown
  • (Craig turns away and looks through his papers)
  • Craig: “Isn’t it true that the only viable quantum gravity models on order today involve a beginning – have a finite past?”
  • Krauss: “No”
  • Craig: “Well, can you give us one then”
  • Krauss: (talks about a variety of possible eternal models) “In my experience in science, all of them are probably wrong”
  • Krauss: “You know most theories are wrong, which is why, you know, it’s hard”
  • Craig: “Right”

Krauss accused Dr. Craig of misrepresenting science many times in his three Australia debates, but now we know the truth about who misrepresented science.

UPDATE: This whole episode made me think of a lecture by famous physicist Richard Feynman.

Excerpt:

The first principle is that you must not fool yourself–and you are the easiest person to fool. So you have to be very careful about that. After you’ve not fooled yourself, it’s easy not to fool other scientists. You just have to be honest in a conventional way after that.

I would like to add something that’s not essential to the science, but something I kind of believe, which is that you should not fool the layman when you’re talking as a scientist. I am not trying to tell you what to do about cheating on your wife, or fooling your girlfriend, or something like that, when you’re not trying to be a scientist, but just trying to be an ordinary human being. We’ll leave those problems up to you and your rabbi.  I’m talking about a specific, extra type of integrity that is not lying, but bending over backwards to show how you are maybe wrong, that you ought to have when acting as a scientist. And this is our responsibility as scientists, certainly to other scientists, and I think to laymen.

Now given what Krauss did in the debate, it seems to me that he is not in agreement with Feynman.

UPDATE: Dr. Craig reports that Dr. Krauss refused to let the organizers live-stream the three Australia debates, as well as refusing to let the Australian Broadcasting Corporation live-broadcast the three debates.