2013 YAMAUCHI LECTURE
NEW LIFE FOR OLD PROOFS
OF THE EXISTENCE OF GOD
by Doug Ward
OXFORD, OHIO-For over two thousand years philosophers and theologians have wrestled with the question of God's existence.1 In 2013 this question is attracting as much interest and controversy as it ever has, thanks in part to the advances in science that have taken place since 1900. Developments like big bang cosmology and the apparent "fine-tuning" of our universe to support life have brought renewed attention to traditional arguments for the existence of a First Cause or Intelligent Designer.2
One philosopher who has been instrumental in reviving and updating these classical arguments for God is Dr. William Lane Craig. Craig, a Research Professor of Philosophy at Talbot Theological Seminary in Los Angeles, is today's foremost evangelical Christian apologist. Through books, public debates and lectures, and his Reasonable Faith website, he gives a vigorous presentation of evidence for theism---Christian theism in particular.
On March 23, 2013, Dr. Craig gave a lecture at Miami University on two traditional proofs for the existence of God. Speaking to an audience of over six hundred, he discussed these proofs in light of modern research in astrophysics and cosmology.
The Big Bang and the Cosmological Argument
Craig talked first about the cosmological argument, one version of which can be summarized as follows:
1. Everything that has a beginning has a cause.
2. The universe had a beginning.
3. Therefore, the universe has a cause.
Craig traces this form of the argument, which he has labeled the Kalam Cosmological Argument, back to the medieval Islamic philosopher Al-Ghazali (1058-1111).3 It is a simple syllogism that forces anyone who agrees with the premises (steps 1 and 2) to accept the conclusion (step 3) also.
Step 2 has always been the more controversial of the two premises. There are philosophical arguments for step 2 based on the impossibility of an actual infinity existing in reality. By one such line of reasoning, if the universe had no beginning, then there would be an infinite sequence of past events. Since an actual infinity cannot exist in reality, the universe must have had a beginning.4
There is also scientific evidence supporting step 2. In the 1920s Russian mathematician Alexander Friedmann and Belgian astronomer Georges Lemaitre, working independently, found solutions of Einstein's equations of general relativity that predicted an expanding universe. Then in 1929, American astronomer Edwin Hubble provided experimental verification of the Friedman-Lemaitre model. Hubble found that light from distant galaxies is shifted toward the red end of the spectrum, an indication that the universe is indeed expanding. So if the universe were "rewound", it would contract in size, back to some time in the past when all the matter in the universe was concentrated in one place. At that moment a "Big Bang" apparently occurred, the initial event in the history of the universe.
What led up to the Big Bang? One currently popular theory proposes that our universe was generated as part of the expansion process of another one, which was in turn generated by another one, et cetera. In this scenario, our universe is part of a "multiverse" of worlds.
At first this might seem to be a way around the cosmological argument. However, Craig explained that in 2003, Arvind Borde, Alan Guth, and Alexander Vilenkin proved that in any expanding multiverse scenario, the universe-forming process would have to have a beginning. The cosmological argument then still would be valid, with the word "universe" defined to mean the entire multiverse.
The cosmological argument gives us good reason to believe that the universe (appropriately defined) had a "first cause". What can be said about this cause? Craig argues that since it is external to the universe, it must transcend space and time. Therefore the first cause would be changeless and immaterial, uncaused and without a beginning. It would also have to be unimaginably powerful to be able to orchestrate the initial Big Bang.
Further, Craig reasons that there are two kinds of causal explanations: (a) scientific explanations expressed via physical laws and initial conditions; (b) personal explanations involving agents and their volitions. Since nothing scientific exists before the beginning of the universe, Craig concludes that the first cause is personal in nature, so that the first cause is "a personal agent who freely chooses to create a universe in time."5 This first cause sounds a lot like the Being we call God.
Fine-Tuning and the Teleological Argument
Dr. Craig then turned to the teleological argument, or argument from design. This is probably the oldest proof for the existence of God, reasoning from the order and beauty in the universe to the existence of a divine Designer. As we read in Psalm 19, "The heavens declare the glory of God; and the firmament sheweth his handywork."
The teleological argument has gained renewed support in light of mounting evidence that the universe seems to be specially "fine-tuned" to allow the existence of life.6 In the physical laws of the universe, formulated as equations, there are constants not determined by the equations themselves. There are other constants that are boundary conditions for the universe. For the universe to support intelligent life, many of these numbers are required to fall into astoundingly narrow ranges. For example, changes in either the gravitational constant or weak force constant of only 10-100 times their values would preclude the existence of life. Similarly, if a parameter governing the expansion rate of the universe right after the Big Bang were slightly smaller, the universe would have recollapsed long ago; while if that parameter were slightly higher, the galaxies would not have been able to form. 7
Craig said that a teleological argument based on fine-tuning would assess the likelihood of all the possible explanations for the evidence we have. He asserted that the three possibilities are necessity, chance, and design. For "necessity" to be the answer, there would have to be physical laws and equations that would single out our universe as the only possible one. Scientists do not anticipate that this is the case. For example, it is estimated that string theory allows 10500 possible universes governed by our laws of nature.
In considering the possibility of chance as an explanation for fine-tuning, some point out that the only kind of universe we could possibly observe is one that is fine-tuned for our existence. But this does not make such an event likely. A helpful analogy is a scenario where a firing squad of a hundred skilled marksmen fires at me. The only way I could notice that they all missed would be if they all missed, but I would still be very surprised to survive the attempted execution.
If our universe is part of a multiverse of many worlds, there would be a greater possibility of the existence of at least one universe that supports life. But in a large collection of randomly-generated universes, what would a typical life-supporting universe look like? Here, Craig stated, the laws of thermodynamics suggest an answer. He cited an estimate by physicist Roger Penrose that the odds of a random universe having the low entropy of our universe were on the order of 1 to 1010^23. A random observable universe would almost certainly have a smaller region of thermal disequilibrium than ours and would very likely contain the observer and nothing else.
Professor Craig concluded that chance is not a credible explanation of the fine-tuning for life that exists in our universe. Design is the most likely explanation for the universe's existence, even if the universe is part of a much larger multiverse.
The cosmological and teleological arguments have ancient roots but are still powerful chains of reasoning in the twenty-first century.8 Although the people most inclined to accept these arguments are those who believe in God already, the arguments still serve important purposes. In particular, Dr. Craig's lecture undoubtedly strengthened the faith of many theists who were in attendance.
1An engaging history of the quest to prove or disprove God's existence is given by journalist Nathan Schneider in his book, God in Proof: The Story of a Search from the Ancients to the Internet, University of California Press, Berkeley, 2013.
2See God in Proof, Chapter 9.
3In chapter 3 of his book Reasonable Faith (Third Edition, Crossway Books, 2008), Craig explains, " `Kalam' is the Arabic word for speech and came to denote a statement of theological doctrine and ultimately the whole movement of medieval Islamic theology."
4Craig carefully discusses the premises of the cosmological argument in chapter 3 of Reasonable Faith.
5Reasonable Faith, Chapter 3.
6I have previously discussed this issue in the article, "Is There a Place in Science for Belief in Design?" in Issue 16 of Grace & Knowledge.
7For more discussion, see Reasonable Faith, Chapter 4.
8Additional proofs of God's existence, such as the ontological and moral arguments, are also stated and defended in Chapters 3 and 4 of Reasonable Faith.
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On 13 Aug 2013, 12:40.