Wintery Knight

…integrating Christian faith and knowledge in the public square

William Lane Craig debates Austin Dacey: Does God Exist?

Here is the video and summary of a debate between Christian theist William Lane Craig and Austin Dacey at Purdue University in 2004 about the existence of God.

The debaters:

The video: (2 hours)

The video shows the speakers and powerpoint slides of their arguments. Austin Dacey is one of the top atheist debaters, and I would put him second to Peter Millican alone, with Walter Sinnott-Armstrong in third place. This is the debate to show people who are new to apologetics. The debate with Peter Millican is better for advanced students, and that’s no surprise since he teaches at Oxford University and is familiar with all of Dr. Craig’s work. The Craig-Dacey debate is the one that I give to my co-workers.

By the way, you can get the DVDs and CDs for the first Craig-Dacey debate and the second Craig-Dacey debate and the second Craig-Sinnott-Armstrong debate. The Peter Millican debate is not available on DVD, but the link above (Peter Millican) has the video and my summary.

Dr. Dacey’s 5 arguments below are all good arguments that you find in the academic literature. He is also an effective and engaging speaker, This is a great debate to watch!

SUMMARY of the opening speeches:

Dr. Craig’s opening statement:

Dr. Craig will present six reasons why God exists:

  1. (Contingency argument) God is the best explanation of why something exists rather than nothing
  2. (Cosmological argument)  God’s existence is implied by the origin of the universe
  3. (Fine-tuning argument) The fine-tuning of the universe for intelligent life points to a designer of the cosmos
  4. (Moral argument) God is the best explanation for the existence of objective moral values and objective moral duties
  5. (Miracles argument) The historical facts surrounding the life, death and resurrection of Jesus
  6. (Religious experience) God’s existence is directly knowable even apart from arguments

Dr. Dacey’s opening argument:

There are two ways to disprove God’s existence, by showing that the concept of God is self-contradictory, or by showing that certain facts about ourselves and the world are incompatible with what we would expect to be true if God did exist. Dr. Dacey will focus on the second kind of argument.

  1. The hiddenness of God
  2. The success of science in explaining nature without needing a supernatural agency
  3. The dependence of mind on physical processes in the brain
  4. Naturalistic evolution
  5. The existence of gratuitous / pointless evil and suffering

One final point:

One thing that I have to point out is that Dr. Dacey quotes Brian Greene during the debate to counter Dr. Craig’s cosmological argument. Dr. Craig could not respond because he can’t see the context of the quote. However, Dr. Craig had a rematch with Dr. Dacey where was able to read the context of the quote and defuse Dr. Dacey’s objection. This is what he wrote in his August 2005 newsletter after the re-match:

The following week, I was off an another three-day trip, this time to California State University at Fresno. As part of a week of campus outreach the Veritas Forum scheduled a debate on the existence of God between me and Austin Dacey, whom I had debated last spring at Purdue University. In preparation for the rematch I adopted two strategies: (1) Since Dacey had come to the Purdue debate with prepared speeches, I decided to throw him for a loop by offering a different set of arguments for God, so that his canned objections wouldn’t apply. I chose to focus on the cosmological argument, giving four separate arguments for the beginning of the universe, and on the evidence for Jesus’ resurrection. (2) I reviewed our previous debate carefully, preparing critiques of his five atheistic arguments. In the process I found that he had seriously misunderstood or misrepresented a statement by a scientist on the Big Bang; so I brought along the book itself in case Dacey quoted this source again. I figured he might change his arguments just as I was doing; but I wanted to be ready in case he used his old arguments again.

[...]The auditorium was packed that night for the debate, and I later learned that there were overflow rooms, too. To my surprise Dr. Dacey gave the very same case he had presented at Purdue; so he really got clobbered on those arguments. Because he wasn’t prepared for my new arguments, he didn’t even respond to two of my arguments for the beginning of the universe, though he did a credible job responding to the others. I was pleased when he attacked the Big Bang by quoting the same scientist as before, because I then held up the book, specified the page number, and proceeded to quote the context to show what the scientist really meant.

Dr. Craig is always prepared!

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What are Boltzmann brains, and what challenge do they post to the multiverse hypothesis?

I thought I would turn to the atheist theoretical physicist Sean Carroll, who has previously debated William Lane Craig, to explain to us what a Boltzmann brain is, and what threat it posts to the multiverse hypothesis.

Here is Sean Caroll, quoted by About.com:

Ludwig Boltzmann was one of the founders of the field of thermodynamics in the nineteenth century. One of the key concepts was the second law of thermodynamics, which says that the entropy of a closed system always increases. Since the universe is a closed system, we would expect the entropy to decrease over time. This means that, given enough time, the most likely state of the universe is one where everything is the in thermodynamic equilibrium … but we clearly don’t exist in a universe of this type since, after all, there is order all around us in various forms, not the least of which is the fact that we exist.

With this in mind, we can apply the anthropic principle to inform our reasoning by taking into account that we do, in fact, exist. Here the logic gets a little confusing, so I’m going to borrow the words from a couple of more detailed looks at the situation. As described by cosmologist Sean Carroll in From Eternity to Here:

Boltzmann invoked the anthropic principle (although he didn’t call it that) to explain why we wouldn’t find ourselves in one of the very common equilibrium phases: In equilibrium, life cannot exist. Clearly, what we want to do is find the most common conditions within such a universe that are hospitable to life. Or, if we want to be more careful, perhaps we should look for conditions that are not only hospitable to life, but hospitable to the particular kind of intelligent and self-aware life that we like to think we are….

We can take this logic to its ultimate conclusion. If what we want is a single planet, we certainly don’t need a hundred billion galaxies with a hundred billion stars each. And if what we want is a single person, we certainly don’t need an entire planet. But if in fact what we want is a single intelligence, able to think about the world, we don’t even need an entire person–we just need his or her brain.

So the reductio ad absurdum of this scenario is that the overwhelming majority of intelligences in this multiverse will be lonely, disembodied brains, who fluctuate gradually out of the surrounding chaos and then gradually dissolve back into it. Such sad creatures have been dubbed “Boltzmann brains” by Andreas Albrecht and Lorenzo Sorbo….

In a 2004 paper, Albrecht and Sorbo discussed “Boltzmann brains” in their essay:

A century ago Boltzmann considered a “cosmology” where the observed universe should be regarded as a rare fluctuation out of some equilibrium state. The prediction of this point of view, quite generically, is that we live in a universe which maximizes the total entropy of the system consistent with existing observations. Other universes simply occur as much more rare fluctuations. This means as much as possible of the system should be found in equilibrium as often as possible.

From this point of view, it is very surprising that we find the universe around us in such a low entropy state. In fact, the logical conclusion of this line of reasoning is utterly solipsistic. The most likely fluctuation consistent with everything you know is simply your brain (complete with “memories” of the Hubble Deep fields, WMAP data, etc) fluctuating briefly out of chaos and then immediately equilibrating back into chaos again. This is sometimes called the “Boltzmann’s Brain” paradox.

[...]Now that you understand Boltzmann brains as a concept, though, you have to proceed a bit to understanding the “Boltzmann brain paradox” that is caused by applying this thinking to this absurd degree. Again, as formulated by Carroll:

Why do we find ourselves in a universe evolving gradually from a state of incredibly low entropy, rather than being isolated creatures that recently fluctuated from the surrounding chaos?

Unfortunately, there is no clear explanation to resolve this … thus why it’s still classified as a paradox.

Naturalists like to propose the multiverse as a way of explaining away the fine-tuning that we see, and explaining why complex, embodied intelligent beings like ourselves exist. But even if the multiverse hypothesis were true, we still would not expect to observe stars, planets, and conscious embodied intelligent beings. It is far more likely on a multiverse scenario that any observers we had would be “Boltzmann” brains in an empty universe. The multiverse hypothesis doesn’t explain the universe we have, which contains “a hundred billion galaxies with a hundred billion stars each” – not to mention our bodies which are composed of heavy elements, all of which require fine-tuning piled on fine-tuning piled on fine-tuning.

William Lane Craig answered a question about Boltzmann brains a while back, so let’s look at his answer since we saw what his debate opponent said above.

He writes:

Incredible as it may sound, today the principal–almost the only–alternative to a Cosmic Designer to explain the incomprehensibly precise fine tuning of nature’s constants and fundamental quantities is the postulate of a World Ensemble of (a preferably infinite number of) randomly ordered universes. By thus multiplying one’s probabilistic resources, one ensures that by chance alone somewhere in this infinite ensemble finely tuned universes like ours will appear.

Now comes the key move: since observers can exist only in worlds fine-tuned for their existence, OF COURSE we observe our world to be fine-tuned! The worlds which aren’t finely tuned have no observers in them and so cannot be observed! Hence, our observing the universe to be fine-tuned for our existence is no surprise: if it weren’t, we wouldn’t be here to be surprised. So this explanation of fine tuning relies on (i) the hypothesis of a World Ensemble and (ii) an observer self-selection effect.

Now apart from objections to (i) of a direct sort, this alternative faces a very formidable objection to (ii), namely, if we were just a random member of a World Ensemble, then we ought to be observing a very different universe. Roger Penrose has calculated that the odds of our solar system’s forming instantaneously through the random collision of particles is incomprehensibly more probable that the universe’s being fine-tuned, as it is. So if we were a random member of a World Ensemble, we should be observing a patch of order no larger than our solar system in a sea of chaos. Worlds like that are simply incomprehensibly more plentiful in the World Ensemble than worlds like ours and so ought to be observed by us if we were but a random member of such an ensemble.

Here’s where the Boltzmann Brains come into the picture. In order to be observable the patch of order needn’t be even as large as the solar system. The most probable observable world would be one in which a single brain fluctuates into existence out of the quantum vacuum and observes its otherwise empty world. The idea isn’t that the brain is the whole universe, but just a patch of order in the midst of disorder. Don’t worry that the brain couldn’t persist long: it just has to exist long enough to have an observation, and the improbability of the quantum fluctuations necessary for it to exist that long will be trivial in comparison to the improbability of fine tuning.

In other words, the observer self-selection effect is explanatorily vacuous. It does not suffice to show that only finely tuned worlds are observable. As Robin Collins has noted, what needs to be explained is not just intelligent life, but embodied, interactive, intelligent agents like ourselves. Appeal to an observer self-selection effect accomplishes nothing because there is no reason whatever to think that most observable worlds are worlds in which that kind of observer exists. Indeed, the opposite appears to be true: most observable worlds will be Boltzmann Brain worlds.

Allen Hainline explained some of the OTHER problems with the multiverse in a post on Cross Examined’s blog. I recommend taking a look at those as well, because I feel funny even talking about Boltzmann brains. I would rather just say that there is no experimental evidence for the multiverse hypothesis, as I blogged before, and leave it at that. But if the person you are talking to fights you on it, you can disprove the multiverse with the Boltzmann brains.

Filed under: Polemics, , , , , , ,

How brief was the period in which the Cambrian phyla suddenly appeared?

The Cambrian explosion refers to the sudden appearance of new body plans in the fossil record. ID proponents think that the period is between 5-10 million years at the most. Naturalists want to stretch out the period in which the body plans appear to tens of millions of years. The two sides can’t both be right. What’s the truth?

Evolution News has the answer.

Excerpt:

To establish the length of the most explosive period of innovation within the Cambrian explosion itself, Meyer cites the work of MIT geochronologist Samuel Bowring and his colleagues as well the work of another group led by Smithsonian paleontologist Douglas Erwin. The Bowring-led study showed that (in their words) “the main period of exponential diversification” within the Cambrian lasted “only 5-6 million years” (emphasis added). Meyer explains:

An analysis by MIT geochronologist Samuel Bowring has shown that the main pulse of Cambrian morphological innovation occurred in a sedimentary sequence spanning no more than 6 million years. Yet during this time representatives of at least sixteen completely novel phyla and about thirty classes first appeared in the rock record. In a more recent paper using a slightly different dating scheme, Douglas Erwin and colleagues similarly show that thirteen new phyla appear in a roughly 6-million-year window. (p. 73)

[...][T]ake a look first at the following figure that Bowring and his colleagues included in their definitive 1993 article, published in the journal Science. They use radiometric methods to date the different stages of the Cambrian period, including the crucial Tommotian and Atdabanian stages in which the greatest number of new animal phyla and classes arise. Note that the so-called Manykaian stage of the Cambrian period lasts about 10-14 million years. Note also that the main pulse of morphological innovation didn’t begin during this stage but rather during the Tommotian and Atdabanian — a period that they describe as taking between “5 to 10 million years,” and in a more detailed passage as taking about 5-6 million years.

[...]In the figure above, the Tommotian and Atdabanian stages of the Cambrian period together span only about 5 million years, starting at about 530 and ending about 525 million years ago. Bowring’s figure also depicts the total number of classes and orders present at any given time during the Cambrian period. The biggest increases in morphological innovation occur during the Tommotian and Atdabanian stages. Indeed, during this period the number of known orders nearly quadruples. Moreover, Bowring and his colleagues also make clear that this period corresponds to the main pulse of Cambrian morphological innovation as measured by the number of new phyla and classes that first appear. They note that, while a few groups of animals do arise in the earliest Manykaian stage of the Cambrian, the most rapid period of “exponential increase of diversification,” corresponding to the Tommotian and Atdabanian stages, “lasted only 5 to 6 m.y.”

You can see the figure they are reference in the Evolution News article.

Also, check out these clips that explain the Cambrian explosion:

Part 1:

Part 2:

The first clip features James Valentine, a professor of biology at the University of California who just co-authored a new book on the Cambrian explosion and is not a proponent of intelligent design.

The consensus among scientists regarding the period of time in which the new body plans appear is 5-6 million years. Biologically speaking, that’s a blink of an eye. You aren’t going that kind of complexity and innovation in such a short period of time any more than you can expect to win the lottery by buying 5-6 million tickets when the odds of winning are 1 in a googol (10 to the 100th power – 1, followed by 100 zeroes). You don’t have enough lottery tickets to make winning the lottery likely. Similarly, 5-6 million years is not enough time for naturalistic mechanisms to code brand new body plans from scratch. It would be like trying to research and write a Ph.D thesis during a single lunch hour. It’s just not enough time to produce the amount of information that’s required.

Filed under: Polemics, , , , , , , , , , , ,

Mark D. Linville: does Darwinian evolution make morality rational?

Have you ever heard an atheist tell you that naturalistic evolution is an answer to the moral argument? I have. And I found a good reply to this challenge in the book “Contending With Christianity’s Critics“. The chapter that responds to the challenge is authored by Dr. Mark D. Linville. It is only 13 pages long. I have a link to the PDF at the bottom of this post.

First, a bit about the author:

Blog: The Tavern at the End of the World
Current positions:

  • PhD Research Fellow
  • Tutoring Fellow in Philosophy

Education:

  • PhD in Philosophy with a minor in South Asian Studies and a specialization in Philosophy of Religion, University of Wisconsin-Madison
  • MA in Philosophy, University of Wisconsin-Madison
  • MA in Philosophy of Religion, Trinity Evangelical Divinity School
  • MA in Theology, Cincinnati Christian Seminary
  • BA in Biblical Studies, Florida Christian College

Here is his thesis of the essay:

Darwin’s account of the origins of human morality is at once elegant, ingenious, and, I shall argue, woefully inadequate. In particular, that account, on its standard interpretation, does not explain morality, but, rather, explains it away . We learn from Darwin not how there could be objective moral facts, but how we could have come to believe—perhaps erroneously—that there are.

Further, the naturalist, who does not believe that there is such a personal being as God, is in principle committed to Darwinism, including a Darwinian account of the basic contours of human moral psychology. I’ll use the term evolutionary naturalism to refer to this combination of naturalism and Darwinism. And so the naturalist is saddled with a view that explains morality away. Whatever reason we have for believing in moral facts is also a reason for thinking naturalism is false. I conclude the essay with a brief account of a theistic conception of morality, and argue that the theist is in a better position to affirm the objectivity of morality.

And here’s a sample to get your attention:

But even if we are assured that a “normal” person will be prompted by the social instincts and that those instincts are typically flanked and reinforced by a set of moral emotions, we still do not have a truly normative account of moral obligation. There is nothing in Darwin’s own account to indicate that the ensuing sense of guilt—a guilty feeling—is indicative of actual moral guilt resulting from the violation of an objective moral law. The revenge taken by one’s own conscience amounts to a sort of second-order propensity to feel a certain way given one’s past relation to conflicting first-order propensities (e.g., the father’s impulse to save his child versus his impulse to save himself). Unless we import normative considerations from some other source, it seems that, whether it is a first or second-order inclination,one’s being prompted by it is more readily understood as a descriptive feature of one’s own psychology than material for a normative assessment of one’s behavior or character. And, assuming that there is anything to this observation, an ascent into even higher levels of propensities (“I feel guilty for not having felt guilty for not being remorseful over not obeying my social instincts…”) introduces nothing of normative import. Suppose you encounter a man who neither feels the pull of social, paternal or familial instincts nor is in the least bit concerned over his apparent lack of conscience. What, from a strictly Darwinian perspective, can one say to him that is of any serious moral import? “You are not moved to action by the impulses that move most of us.” Right. So?

The problem afflicts contemporary construals of an evolutionary account of human morality. Consider Michael Shermer’s explanation for the evolution of a moral sense—the “science of good and evil.” He explains,

By a moral sense, I mean a moral feeling or emotion generated by actions. For example, positive emotions such as righteousness and pride are experienced as the psychological feeling of doing “good.” These moral emotions likely evolved out of behaviors that were reinforced as being good either for the individual or for the group.2

Shermer goes on to compare such moral emotions to other emotions and sensations that are universally experienced, such as hunger and the sexual urge. He then addresses the question of moral motivation.

In this evolutionary theory of morality, asking “Why should we be moral?” is like asking “Why should we be hungry?” or “Why should we be horny?” For that matter, we could ask, “Why should we be jealous?” or “Why should we fall in love?” The answer is that it is as much a part of human nature to be moral as it is to be hungry, horny, jealous, and in love.3

Thus, according to Shermer, given an evolutionary account, such a question is simply a non-starter. Moral motivation is a given as it is wired in as one of our basic drives. Of course, one might point out that Shermer’s “moral emotions” often do need encouragement in a way that, say, “horniness,” does not. More importantly, Shermer apparently fails to notice that if asking “Why should I be moral?” is like asking, “Why should I be horny?” then asserting, “You ought to be moral” is like asserting, “You ought to be horny.” As goes the interrogative, so goes the imperative. But if the latter seems out of place, then, on Shermer’s view, so is the former.

One might thus observe that if morality is anything at all, it is irreducibly normative in nature. But the Darwinian account winds up reducing morality to descriptive features of human psychology. Like the libido, either the moral sense is present and active or it is not. If it is, then we might expect one to behave accordingly. If not, why, then, as a famous blues man once put it, “the boogie woogie just ain’t in me.” And so the resulting “morality” is that in name only.

In light of such considerations, it is tempting to conclude with C. S. Lewis that, if the naturalist remembered his philosophy out of school, he would recognize that any claim to the effect that “I ought” is on a par with “I itch,” in that it is nothing more than a descriptive piece of autobiography with no essential reference to any actual obligations.

When it comes to morality, we are not interested in mere descriptions of behavior. We want to know about prescriptions of behavior, and whether why we should care about following those prescriptions. We are interested in what grounds our sense of moral obligation in reality. What underwrites our sense of moral obligation? If it is just rooted in feelings, then why should we obey our moral sense when obeying it goes against out self-interest? Feelings are subjective things, and doing the right thing in a real objective state of affairs requires more than just feelings. There has to be a real objective state of affairs that makes it rational for us to do the right thing, even when the right thing is against our own self-interest. That’s what morality is – objective moral obligations overriding subjective feelings. I wouldn’t trust someone to be moral if it were just based on their feelings.

The PDF is right here for downloading, with the permission of the author.

Filed under: Polemics, , , , , , , , , , , , , ,

Peter J. Williams lectures on the historical reliability of the gospel narratives

Peter J. Williams

Peter J. Williams

Here’s the main lecture: (54 minutes)

And here’s the Q&A: (9 minutes)

About Peter Williams:

Peter J. Williams is the Warden (CEO) of Tyndale House and a member of the Faculty of Divinity in the University of Cambridge. He received his MA, MPhil and PhD, in the study of ancient languages related to the Bible from Cambridge University. After his PhD, he was on staff in the Faculty of Divinity, Cambridge University (1997–1998), and thereafter taught Hebrew and Old Testament there as Affiliated Lecturer in Hebrew and Aramaic and as Research Fellow in Old Testament at Tyndale House, Cambridge (1998–2003). From 2003 to 2007 he was on the faculty of the University of Aberdeen, Scotland, where he became a Senior Lecturer in New Testament and Deputy Head of the School of Divinity, History and Philosophy. In July 2007 he became the youngest Warden in the history of Tyndale House. He also retains his position as an honorary Senior Lecturer in Biblical Studies at the University of Aberdeen.

Summary of the lecture:

  • What if the stories about Jesus are legendary?
  • were the gospels transmitted accurately?
  • were the gospels written in the same place as where the events happened?
  • do the gospel authors know the customs and locations where the events happened?
  • do the gospels use the right names for the time and place where the events took place?
  • do the gospels disambiguate people’s names depending on how common those names were?
  • how do the New Testament gospels compare to the later gnostic gospels?
  • how do the gospels refer to the main character? How non-Biblical sources refer to Jesus?
  • how does Jesus refer to himself in the gospels? do the later Christians refer to him that way?
  • how does Jesus teach? do later Christians teach the same way?
  • why didn’t Jesus say anything about early conflicts in the church (the Gentiles, church services)?
  • did the writers of the gospels know the places where the events took place?
  • how many places are named in the gospels? how about in the later gnostic gospels?
  • are the botanical details mentioned in the gospels accurate? how about the later gnostic gospels?

And here are the questions from the audience:

  • how what about the discrepancies in the resurrection narratives that Bart Ehrman is obsessed with?
  • what do you think of the new 2011 NIV translation (Peter is on the ESV translation committee)?
  • how did untrained, ordinary men produce complex, sophisticated documents like the gospels?
  • is oral tradition a strong enough bridge between the events and the writers who interviewed the eyewitnesses?
  • what does the name John mean?
  • why did the gospel writers wait so long before writing their gospels?
  • do you think that Matthew and Luke used a hypothetical source which historians call “Q”?
  • which gospel do critical historians trust the least and why?

I really enjoyed watching this lecture. He’s getting some of this material from Richard Bauckham’s awesome book “Jesus and the Eyewitnesses”, so if you aren’t familiar with it, you can get an idea of what’s in it. Peter Williams is a lot of fun to listen to – an excellent speaker.

You can read an interview with Peter Williams here on Between Two Worlds.

And you can listen to the Peter Williams vs Bart Ehrman debate. That link contains a link to the audio of the debate as well as my snarky summary. It’s very snarky.

And Apologetics 315 also posted Peter Williams’ assessment of Bart Ehrman’s “Misquoting Jesus”.

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