Tuesday, March 16, 2010

Loftus vs. Wood: An Atheist-Theist Debate

Here's a link to a debate entitled "Does God Exist?", featuring David Wood (theist) versus John Loftus (atheist).

I wasn't impressed at all with Wood's argument, which went roughly as follows:

1. He claimed that "Atheists have held that the Universe is eternal ... Much to the horror of atheists, research in the 20th century showed that the Universe is expanding, and we can therefore trace its development back to a beginning."

I think this misrepresents the case. Some physicists supported a steady-state universe (and some few still do), and some opposed it. But I see no evidence that atheists came down overwhelmingly on one side or the other. And I see no evidence today that atheists regard the Big Bang theory with "horror". Why should we? The Big Bang doesn't imply a magical creator.

2. He claimed that "Either the Universe began to exist as the result of some cause, or the Universe sprang into existence uncaused. The second alternative is obviously absurd - out of nothing, nothing comes."

Not much of an argument. First, we see apparently uncaused events all the time in radioactive decay. When a particular Americium atom decays in your smoke detector, what causes that one to decay rather than some other one? Nothing that we know. Second, even in a vacuum, virtual particles come into existence all the time and are measurable. So appealing to naive folk wisdom like "out of nothing, nothing comes" when modern physics contradicts this --- it's not intellectually honest.

3. He gave an argument about fine tuning. "These numbers [constants of physics] could have had a wide range of values, and yet the values they actually have fall into the extremely narrow range that makes biological life possible."

How does Wood know that the constants of physics "could have had a wide range of values"? Answer: he doesn't - it's just an assertion. Maybe because of something about physics we don't know, only a narrow range of constants is possible.

How does Wood know that tweaking the constants would usually result in an unlivable universe? Answer: he doesn't. Vic Stenger has modeled universes where the constants can change, and found that a relatively wide range of constants still allowed interesting physics.

How does Wood know that tweaking the constants couldn't result in some other completely different form of life? Answer: he doesn't.

4. He argued that the complexity of biology implies a Designer: "Where did Earth's diverse biological complexity come from? The most obvious explanation is design."

Yes, that may have been true before 1859, back in the day when our ideas about biology were so primitive that many physicians rejected the germ theory of disease. But a lot has happened since then, much of it due to another D-word: Darwin. We now have a strongly-supported theory that can account for biological complexity -- the theory of evolution -- so to pretend that we must stick with the "obvious explanation" 150 years later is dishonest.

5. He claimed that consciousness requires a "soul". "I can have a thought about a grilled cheese sandwich - I can't have a pattern of molecules about a grilled cheese sandwich".

Why not? I see no logical or physical problem in maintaining that I can have a thought about a grilled cheese sandwich and that this thought ultimately reduces to matter and energy in my brain. Much of Wood's argument seemed like this: pure assertion.

"If a scientist examines my brain he might learn all kind of things about my brain that I don't know, but he'll never learn more about my mind than I know."

Why not? What logical or scientific principle would prevent us, for example, from being able to access the subconscious through a physical examination of the brain, resulting in knowledge of (say) a repressed memory that you don't "know" consciously?

6. "We know scientifically that the mind can function even when the brain stops working. There are numerous cases in medical journals of people who are clinically dead, showing no brain activity at all, being brought back to life and reporting that they had conscious experiences while they were dead."

Near-death experiences typically occur during medical crises, when (for example) the brain might be starved of oxygen. If we don't consider the testimony of drunk people reliable, why should we consider the testimony of oxygen-starved brains as reliable? Claims about near-death experiences have been exaggerated and research has been plagued by poor experiment design; see the chapter by Hövelmann in the Skeptic's Handbook of Parapsychology.

7. Naturalism must be able to account for the coherence of human reason: "According to John, our ability to reason is the product of natural selection acting on random mutation ... Does this give us any basis for trusting our reasoning ability when it comes to questions of theology or philosophy or science?"

Here he's stealing - without attribution - C. S. Lewis's argument against naturalism, which has also been argued by Plantinga and others. I find this argument one of the dumbest around. Study after study shows that humans are not always good reasoners: we routinely mishandle basic probability, we make snap judgments based on appearances, and we have unconscious biases. But there's also good empirical evidence (like the existence of spaceships and toasters) that we somehow manage to muddle along and figure things out much of the time. We're simply stuck with the reasoning ability we have, and the heuristics -- known as science -- we've deduced over thousands of years to make sure that our conclusions are correct. It's not like religion comes up with conclusions that we can have confidence in. Which would give you more confidence in a plane never flown in the air before: calculations and simulations by trained engineers, or the blessing of a priest?

8. "Our reasoning is governed by certain logical truths ... we are presupposing that there are logical absolutes - rules of reasoning that cannot be violated... A statement cannot be both true and false at the same time. But what are logical laws? They are not material objects. We don't learn about them through the senses... Logical laws don't depend on human minds. The law of non-contradiction was true before there were any human beings, and if all human beings died tomorrow they would still be true. In fact, the laws of logic would be true in any universe, not just ours. So the laws of logic transcend time, space, matter, and all human minds - they're invariant, unchanging, and eternal."

Spoken by someone who has clearly never heard of multi-valued logic. And is the axiom of choice true or false? When Wood says "the laws of logic would be true in any universe, not just ours", how does he know this? Does he have intimate knowledge of other universes?

In the clever words of philosopher Tim Kenyon, there aren't laws of thought. It's more like "municipal by-laws" of thought.

I might add that Wood gave us no reason to believe that there aren't multiple gods, or even infinitely many.

Unfortunately, Loftus' performance was not very impressive either. Although he made a lot of good points, he read his opening presentation from notes, mumbled too much, stumbled over pronunciations (like "plate tectonics"), made too many joking asides that weren't funny and chuckled at them, sounded a bit patronizing, didn't really connect with the audience, and didn't consistently offer strong rebuttals to Wood's points.

24 comments:

Timothy said...

Hello,
Relatively-new reader, first-time commenter here. I quite enjoy reading your blog!

I have an actual comment regarding your response to Wood on point number 8, but to make sure I understand you I wanted to ask a question first. What parts of Wood's statement are you saying are refuted by the existence of multi-valued logic?

Jeffrey Shallit said...

Timothy:

The claim that there are "laws of logic" which are "eternal". But in multi-valued logic, some of Wood's claimed "laws" don't hold.

edthemanicstreetpreacher said...

OK, this is just getting silly now. John W says that Hawking and Penrose no longer believe in the Big Bang singularity and gives the page number from A Brief History of Time where Hawking recants their earlier thesis.

And then in two of his rebuttals, David quote-mines Hawking as accepting that “today, nearly everyone believes that the universe started with the Big Bang”.

Hawking was referring to the lasting impact on the lay-public’s consciousness of his and Penrose’s earlier thesis! Hawking makes clear the very next sentence that he no longer supports this thesis, but David stops quoting at that point!

It’s like Hawking says he doesn’t believe in the tooth fairy, but still recognises that most people do, and David so has appealed to Hawking’s authority to support his belief in the tooth fairy.

DISGRACEFUL!

Timothy said...

Ok, thanks for responding. Now for my comment: Don't you think Wood was most likely talking specifically about classical logic, seeing as how that is what people generally mean when they use the word "logic"? Doesn't Wood just mean that there are logical absolutes when it comes to preserving "truth," as opposed to preserving "justification" or any other concepts that various systems of logic have been developed to preserve? For example, the law of noncontradiction is absolute in truth-preserving logic, and forms the basis of all of our science, philosophy, and reasoning that we do in everyday life.

Now don't get me wrong - I still disagree with Wood if he is trying to conclude based on the immutability of logical laws that there is a god. That conclusion just doesn't follow. Still, I thought your response didn't really address that issue...

Jeffrey Shallit said...

Yes, probably Wood was talking about classical logic. But the existence of other logics that are used and studied shows that classical logic isn't eternal, immutable, etc. - what we pick to be our basis for logic is more a matter of convention. That's why I spoke of "municipal by-laws of thought", not "laws of thought".

Miranda said...

You raised some good points, Jeffrey. Just one critique, and a question for you or your readers.

"out of nothing, nothing comes."
"When a particular Americium atom decays in your smoke detector, what causes that one to decay rather than some other one?"

But still, an Americium atom is something, right?

"Some physicists supported a steady-state universe (and some few still do), and some opposed it. But I see no evidence that atheists came down overwhelmingly on one side or the other."

Can anyone provide some good history as to the positions of the leading physicists of the time, the time when the Big Bang Theory was gaining momentum?

Jeffrey Shallit said...

Miranda:

Thanks for your comments.

The comment about americium was intended to support my first claim (that apparently uncaused events occur) and not the second claim (that "out of nothing, nothing comes" was incorrect).

John W. Loftus said...

I think as a scientist you approach things as a scientist would. I approach things from my perspective. I think the theistic arguments on behalf of God are a shell game. I try to offer a more fundamental critique of this game of theirs but I learn from people like you.

cody said...

"Which would give you more confidence in a plane never flown in the air before: calculations and simulations by trained engineers, or the blessing of a priest?"

This reminds me of Sagan's quote,

"We have designed our civilization based on science and technology and at the same time arranged things so that almost no one understands anything at all about science and technology. This is a clear prescription for disaster."

It is interesting that while most people probably fit well into Sagan's description, most would (I think & HOPE) still side with you on the engineered plane.

Is it that people trust the engineers to make the plane work, but don't realize that the way they do so is by skeptically sorting information through repeated rigorous testing, rather than through some magical "...coherence of human reason" or a "...basis for trusting our reasoning ability..."?

Do most people not understand that evidence is king? That human reasoning is garbage where ever it disagrees with empirical evidence? Is there a way for me to debate people like Wood? I need a new job, and promoting reason in a public forum would help me sleep at night.

Bayesian Bouffant, FCD said...

5. He claimed that consciousness requires a "soul". "I can have a thought about a grilled cheese sandwich - I can't have a pattern of molecules about a grilled cheese sandwich".

Mind-reading experiment uses brain scans to eavesdrop on thoughts
Brain scans revealed with reasonable accuracy which short film clip volunteers were thinking about
March 11, 2010

Bayesian Bouffant, FCD said...

3. He gave an argument about fine tuning. "These numbers [constants of physics] could have had a wide range of values, and yet the values they actually have fall into the extremely narrow range that makes biological life possible."

From the January 2010 Scientific American:
Looking for Life in the Multiverse
Universes with different physical laws might still be habitable
By Alejandro Jenkins and Gilad Perez

Jeffrey Shallit said...

Thanks for stopping by, John. I admire your courage in participating in these public debates, and I'm confident your performance will improve in future debates. Best of luck to you!

carl said...

Another nice post. I think most of your retorts are decisive and to the point.

However, on a couple, while you make a relevant and accurate point, it seems that there is a stronger position to take against such nonsense. Specifically, concerning the logic example, I don't see why you should get sucked into talking about alternative logics. Modus ponens is not merely a convention. That's just silly. The issue is, who cares if the laws of logic are necessary truths? That has absolutely nothing to do with whether or not a god exists. Necessary truths like logic can be explained in various ways without any supernatural, magical beings. And, more importantly, supernatural beings cannot make the laws of logic true. God cannot by decree, by fiat, or by wave of god's magic wand make modus ponens a law of logic, and certainly cannot make it hold necessarily. It makes no sense. It has nothing to do with any gods.

Anonymous said...

cody: promoting reason in a public forum would help me sleep at night.


or drive you insane


jah

edthemanicstreetpreacher said...

@Jeffrey – Do you do public debates? Your blog terrific. I think you’d flattened God squadders like Wood and D’Souza at the lectern.

MSP

Anonymous said...

The Big Bang has been misappropriated by Christian wingnuts. Unfortunately scientists who should know better have never done anything to set the record straight

Truti

ChristianJR4 said...

Surprise surprise! edthemanicstreetpreacher posts a comment about misrepresentation and yet he AGAIN is the one guilty of it.

For the last time ed, apologists aren't quoting Hawking for his beliefs on the Big Bang singularity. They are quoting him for his summation of the consensus position among cosmologists concerning the beginning. Nowhere in this debate did David make the argument that Hawking believes the universe started with a singularity. Apart from a mistaken equivocation of the singularity with beginning in his first rebuttal, he wasn't making that point. His point was simply that the universe had a beginning.

And Hawking was not referring to the "lay public's consciousness". He was referring to the position of actual cosmologists. Here's the full quote from Hawking:

"So in the end our work became generally accepted and nowadays nearly everyone assumes that the universe started with a big bang singularity. It is perhaps ironic that, having changed my mind, I am now trying to convince other physicists that there was no singularity at the beginning.

--Stephen Hawking, "A Brief History of Time", p. 67 (illustrated);...emphasis mine

It's pretty obvious he's talking about cosmologists here, not your average joe on the street. Indeed, he couldn't possibly be talking about the lay public. Which lay public? Americans? Certainly not. Almost half of them believe the world is less than 10,000 years old. How about the British? A considerable number of them do as well, enough not to make it "nearly everyone" as Hawking says. Moreover, a lot of people couldn't even tell you what the Big Bang is, much less what a singularity is.

So once again, stop misrepresenting the picture yourself. Apologists may be wrong in what they think their arguments show, but I see no misrepresentation on their part here. I can't say the same for you.

NotNecessary said...

Carl, how can you even explain or account for our ability to *conceive* of necessary truths on the basis of what the evidence shows us to be, finite patterns of physical stuff that arose from nothing but the laws of physics and random initial conditions? We have to hold the line against people who think we have correct conceptions of such things, which are nowhere to be observed in experience.

Miranda said...

Anonymous writes, "The Big Bang has been misappropriated by Christian wingnuts. "

How?

John W. Loftus said...

I thought you might be interested in this response from Doug Krueger. It's not about this debate per se, only about what I attempted to do.

Cheers.

Anonymous said...

yes, but what does "exist" mean?
is that the real question?

edthemanicstreetpreacher said...

@ChristianJR4

You can argue over syntax and semantics all you like. I stand by my comments that the likes of Wood, Craig and D’Souza are misappropriating the words of atheist scientists like Hawking to make it appear that they support the religious version of cosmology.

Like all those apologists who still keep claiming that Einstein was a theist because he used the word “God” to refer to physics.

Rather like Deepak Chopra did last week during the ABC discussion with Sam Harris and Michael Shermer now you come to mention it.

End of.

Anonymous said...

Re "I can have a thought about a grilled cheese sandwich - I can't have a pattern of molecules about a grilled cheese sandwich":

Seems a bit like arguing that an H2O molecule is not "wet" and therefore water does not consist of H2O molecules.

As to Wood's (probably apocryphal) account of revivals from brain-death: assuming the brain has not yet undergone any structural degradation, there would not seem to be any reason such a patient could not be revived. The fact that it can't be done when there is sufficient structural degradation completely refutes Wood's mysticism about independence of mind and brain.

Anonymous said...

Also, Professor Shallit, I think your reply to Wood in point 8 is unnecessarily sophisticated. The truly ridiculous fallacy occurs right after the statements you quote. Wood goes on to say that logic is eternal and exists only in a mind and therefore there must exist an eternal mind. It's akin to saying that because the statement "2+2=4" is true, and was true before humans existed, and will continue to be true after we've all murdered one another with nuclear weapons, there must therefore exist an eternal, incorporeal abacus in the heavens in order to maintain the truth of that equation.