Tag Archives: Progress of Science

Videos

William Lane Craig debates Austin Dacey: Does God Exist?

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Two tough rams butt heads, and may the best ram win!
Two tough rams butt heads, and may the best ram win!

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!

Polemics

Alexander Vilenkin: “All the evidence we have says that the universe had a beginning”

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I’ve decided to explain why physicists believe that there was a creation event in this post. That is to say, I’ve decided to let famous cosmologist Alexander Vilenkin do it.

From Uncommon Descent.

Excerpt:

Did the cosmos have a beginning? The Big Bang theory seems to suggest it did, but in recent decades, cosmologists have concocted elaborate theories – for example, an eternally inflating universe or a cyclic universe – which claim to avoid the need for a beginning of the cosmos. Now it appears that the universe really had a beginning after all, even if it wasn’t necessarily the Big Bang.

At a meeting of scientists – titled “State of the Universe” – convened last week at Cambridge University to honor Stephen Hawking’s 70th birthday, cosmologist Alexander Vilenkin of Tufts University in Boston presented evidence that the universe is not eternal after all, leaving scientists at a loss to explain how the cosmos got started without a supernatural creator. The meeting was reported in New Scientist magazine (Why physicists can’t avoid a creation event, 11 January 2012).

[…]In his presentation, Professor Vilenkin discussed three theories which claim to avoid the need for a beginning of the cosmos.

The three theories are chaotic inflationary model, the oscillating model and quantum gravity model. Regular readers will know that those have all been addressed in William Lane Craig’s peer-reviewed paper that evaluates alternatives to the standard Big Bang cosmology.

But let’s see what Vilenkin said.

More:

One popular theory is eternal inflation. Most readers will be familiar with the theory of inflation, which says that the universe increased in volume by a factor of at least 10^78 in its very early stages (from 10^−36 seconds after the Big Bang to sometime between 10^−33 and 10^−32 seconds), before settling into the slower rate of expansion that we see today. The theory of eternal inflation goes further, and holds that the universe is constantly giving birth to smaller “bubble” universes within an ever-expanding multiverse. Each bubble universe undergoes its own initial period of inflation. In some versions of the theory, the bubbles go both backwards and forwards in time, allowing the possibility of an infinite past. Trouble is, the value of one particular cosmic parameter rules out that possibility:

But in 2003, a team including Vilenkin and Guth considered what eternal inflation would mean for the Hubble constant, which describes mathematically the expansion of the universe. They found that the equations didn’t work (Physical Review Letters, DOI: 10.1103/physrevlett.90.151301). “You can’t construct a space-time with this property,” says Vilenkin. It turns out that the constant has a lower limit that prevents inflation in both time directions. “It can’t possibly be eternal in the past,” says Vilenkin. “There must be some kind of boundary.”

A second option explored by Vilenkin was that of a cyclic universe, where the universe goes through an infinite series of big bangs and crunches, with no specific beginning. It was even claimed that a cyclic universe could explain the low observed value of the cosmological constant. But as Vilenkin found, there’s a problem if you look at the disorder in the universe:

Disorder increases with time. So following each cycle, the universe must get more and more disordered. But if there has already been an infinite number of cycles, the universe we inhabit now should be in a state of maximum disorder. Such a universe would be uniformly lukewarm and featureless, and definitely lacking such complicated beings as stars, planets and physicists – nothing like the one we see around us.

One way around that is to propose that the universe just gets bigger with every cycle. Then the amount of disorder per volume doesn’t increase, so needn’t reach the maximum. But Vilenkin found that this scenario falls prey to the same mathematical argument as eternal inflation: if your universe keeps getting bigger, it must have started somewhere.

However, Vilenkin’s options were not exhausted yet. There was another possibility: that the universe had sprung from an eternal cosmic egg:

Vilenkin’s final strike is an attack on a third, lesser-known proposal that the cosmos existed eternally in a static state called the cosmic egg. This finally “cracked” to create the big bang, leading to the expanding universe we see today. Late last year Vilenkin and graduate student Audrey Mithani showed that the egg could not have existed forever after all, as quantum instabilities would force it to collapse after a finite amount of time (arxiv.org/abs/1110.4096). If it cracked instead, leading to the big bang, then this must have happened before it collapsed – and therefore also after a finite amount of time.

“This is also not a good candidate for a beginningless universe,” Vilenkin concludes.

So at the end of the day, what is Vilenkin’s verdict?

“All the evidence we have says that the universe had a beginning.”

This is consistent with the Borde-Guth-Vilenkin Theorem, which I blogged about before, and which William Lane Craig leveraged to his advantage in his debate with Peter Millican.

The Borde-Guth-Vilenkin (BGV) proof shows that every universe that expands must have a space-time boundary in the past. That means that no expanding universe, no matter what the model, can be eternal into the past. No one denies the expansion of space in our universe, and so we are left with a cosmic beginning. Even speculative alternative cosmologies do not escape the need for a beginning.

Conclusion

If the universe came into being out of nothing, which seems to be the case from science, then the universe has a cause. Things do not pop into being, uncaused, out of nothing. The cause of the universe must be transcendent and supernatural. It must be uncaused, because there cannot be an infinite regress of causes. It must be eternal, because it created time. It must be non-physical, because it created space. There are only two possibilities for such a cause. It could be an abstract object or an agent. Abstract objects cannot cause effects. Therefore, the cause is an agent.

Now, let’s have a discussion about this science in our churches, and see if we can’t train Christians to engage with non-Christians about the evidence so that everyone accepts what science tells us about the origin of the universe.

News

Are solar eclipses common? What has to be in place to observe a solar eclipse?

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Christianity and the progress of science
Christianity and the progress of science

If there were a Designer of the universe, what would He have to do to allow creatures living on a planet to observe a solar eclipse?

Consider this article from Discovery Institute.

Excerpt:

A rare convergence of events allows Earthlings to witness not just solar eclipses, but perfect solar eclipses, where the Moon just barely covers the Sun’s bright photosphere. Such eclipses depend on the precise sizes, shapes, and relative distances of the Sun, Moon, and Earth. There’s no law of physics or celestial mechanics that requires the right configuration. In fact, of the more than 65 major moons in our Solar System, ours best matches the Sun as viewed from its planet’s surface, and this is only possible during a fairly narrow window of Earth’s history encompassing the present. The Moon is about 400 times smaller than the Sun. But right now, the Moon is about 400 times closer to the Earth than is the Sun. So, the Moon’s apparent size on the sky matches the Sun’s. Astronomers have noted this odd coincidence for centuries. And, since the Sun appears larger from the Earth than from any other planet with a moon, an Earth-bound observer can discern finer details in the Sun’s chromosphere and corona than from any other planet. This makes our solar eclipses more valuable scientifically.

The recent pictures of solar eclipses sent back from the Opportunity rover on Mars nicely illustrate how much better our solar eclipses are. The two small potato-shaped Martian moons, Deimos and Phobos, appear much too small to cover the Sun’s disk, and they zip across it in less than a minute.

Not only do you need things to be finely-tuned to see the eclipse, but you also need observers to be there.

More:

It’s intriguing that the best place to view total solar eclipses in our Solar System is the one time and place where there are observers to see them. It turns out that the precise configuration of Earth, Moon and Sun are also vital to sustaining life on Earth. A moon large enough to cover the Sun stabilizes the tilt of the rotation axis of its host planet, yielding a more stable climate, which is necessary for complex life. The Moon also contributes to Earth’s ocean tides, which increase the vital mixing of nutrients from the land to the oceans. The two moons around Mars are much too small to stabilize its rotation axis.

In addition, it’s only in the so-called Circumstellar Habitable Zone of our Sun–that cozy life friendly ring where water can stay liquid on a planet’s surface–that the Sun appears to be about the same size as the Moon from Earth’s surface. As a result, we enjoy perfect solar eclipses.

Why would the Designer of the Universe want his observers to exist in exactly the right place to observe the solar eclipse? What is the point of seeing a solar eclipse?

Here is the point:

Our ability to observe perfect solar eclipses has figured prominently in several important scientific discoveries, discoveries that would have been difficult if not impossible on the much more common planets that don’t enjoy such eclipses.

First, these observations helped disclose the nature of stars. Scientists since Isaac Newton (1666) had known that sunlight splits into all the colors of the rainbow when passed through a prism. But only in the 19th century did astronomers observe solar eclipses with spectroscopes, which use prisms. The combination of the man-made spectroscope with the natural experiment provided by eclipses gave astronomers the tools they needed not only to discover how the Sun’s spectrum is produced, but the nature of the Sun itself. This knowledge enabled astronomers to interpret the spectra of the distant stars. So, in a sense, perfect eclipses were a key that unlocked the field of astrophysics.

Second, in 1919, perfect solar eclipses allowed two teams of astronomers, one led by Sir Arthur Eddington, to confirm a prediction of Einstein’s General Theory of Relativity–that gravity bends light. They succeeded in measuring the changes in the positions of starlight passing near the Sun’s edge compared to their positions months later. Such a test was most feasible during a perfect solar eclipse. The tests led to the general acceptance of Einstein’s theory, which is the foundation of modern cosmology.

So, you’ve got fine-tuning for the eclipse, fine-tuning for the observers, and with that in place, the observers can collect scientific evidence… including evidence that confirms cosmic fine-tuning as well as general relativity. General relativity is important because if gives us the expanding universe – one of the evidences for the Big Bang cosmology. The Big Bang cosmology states that the entire physical universe came into being out of nothing, about 14 billion years ago. Who could have caused that? If we don’t have eclipses, we are losing out on evidence of cosmic fine-tuning and cosmic creation.

There’s a new Discovery Institute podcast featuring Jay Richards, co-author of the amazing book “The Privileged Planet”.

Details:

On this episode of ID: The Future, CSC Senior Fellow Jay Richards explains how perfect solar eclipses are the tip of an iceberg-size design argument found in a book he co-wrote, The Privileged Planet. The conditions for a habitable planet (right distance from the right size star, a big but not too big moon that is the right distance away to stabilize Earth’s tilt and circulate its oceans) are also conditions that make perfect solar eclipses from the Earth’s surface much more likely. And perfect eclipses aren’t just eerie and beautiful. They’ve helped scientists test and discover things, and are part of a larger pattern: The conditions needed for a habitable place in the cosmos correlate with the conditions well suited for scientific discovery. As Richards notes, this correlation is inexplicable if the cosmos is the product of chance. But if it’s intelligently designed with creatures like us in mind, it’s just what we might expect.

The MP3 file is here.

If you have not seen The Privileged Planet, you can get the same argument as in the book in just over an hour. You can either buy The Privileged Planet DVD, or click here to watch it on YouTube. And it’s narrated by John-Rhys Davies.