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The Existence of God (Fine Tuning)

June 10, 2007     Time: 00:11:23
The Existence of God (Fine Tuning)

Summary

Conversation with William Lane Craig

KEVIN HARRIS: Can faith and reason work together, or are they somehow mutually exclusive? What role do facts and evidence play when it comes to the Christian faith? This is Reasonable Faith – Conversations with Dr. William Lane Craig. I’m Kevin Harris. On behalf of Dr. Craig, I want to welcome you to this discussion as Dr. Craig examines apologetics, reason, faith, and philosophy. Today we are examining some of the evidence for the existence of God.

Dr. Craig, the fine-tuning of the universe for life is a real pointer – a real indicator – that God exists.

DR. CRAIG: I think it is, Kevin. I think that one of the signposts of transcendence (as I call them) in the universe pointing to its ground in a supernatural Creator and Designer is the incredible fine-tuning of the initial conditions of the universe for intelligent life which suggests that the universe is not the result of blind chance but rather of intelligent design.

KEVIN HARRIS: Some of the great physicists have looked at this and said, Boy! If the universe were not just this way there would be no life.

DR. CRAIG: That's become commonplace now. This argument is one that I think is the most persuasive to people in the hard natural sciences like physics and astrophysics today because it's become so evident and with increasing clarity that in order for the evolution and existence of intelligent life to take place anywhere in the known cosmos there had to be these elaborately exquisitely finely tuned conditions of the universe in place in the Big Bang itself before any kind of intelligent life could evolve or come to exist. I'm talking about the fine-tuning of the initial conditions of the Big Bang long before there were galaxies and stars and planets and moons. Every indication of further design just adds more and more probability to the argument that this is not the result of chance but of intelligent foresight.

KEVIN HARRIS: You've written that Stephen Hawking has estimated that if the rate of the universe’s expansion one second after the Big Bang had been smaller by even one part in a hundred thousand million million, the universe would have re-collapsed into a hot fireball.

DR. CRAIG: That's exactly correct. The initial conditions of the universe that would be pertinent for the expansion of the universe to be life-permitting have to be exquisitely fine-tuned. Now, some scientists have tried to avoid this by postulating an early era of inflationary expansion to try to explain the precise rate at which the universe is expanding, but this doesn't get rid of the fine-tuning. It just pushes it back a notch, and it requires cosmological fine-tuning of another factor in astronomy called the cosmological constant which helps to fuel the inflationary expansion. Fine-tuning tends to be like a stubborn bump in the carpet. Every time you depress it at one point and try to eliminate it, it tends to pop up at some other point. That's certainly been the pattern. The fine-tuning seems to be illimitable. If you eliminate it at one point, it only recurs at another point.

KEVIN HARRIS: So if the universe is fine-tuned in its initial conditions, that heavily indicates a tuner.

DR. CRAIG: I think it does. There are basically three explanations that could be offered for this remarkable fine-tuning of the universe. One would be chance. It’s just an accident that the initial conditions of the universe were finely tuned. The other would be physical necessity – that somehow nature had to be that way; that the laws of nature require . . .

KEVIN HARRIS: Just natural.

DR. CRAIG: Yes. That this is just natural necessity. And then the third would be that this is the result of intelligent design. What I would argue is that, of those three explanations, the best explanation of the fine-tuning of the universe is intelligent design rather than chance or physical necessity.

KEVIN HARRIS: A lot of people say at this point they object and say if the universe were not so fine-tuned we wouldn't be here to observe it.

DR. CRAIG: That is correct. That's called the Anthropic Principle. The Anthropic Principle says that we can only observe universes which are compatible with our existence, and therefore we really shouldn't be surprised to see a universe that has finely tuned conditions compatible with our existence because if it weren't finely tuned we wouldn't be here to be surprised about it. Therefore there's nothing to be surprised at and nothing that requires explanation. Well, this argument is demonstrably logically fallacious. I think the easiest way to show this would be just to give a parallel illustration. Let me use one that John Leslie, a Canadian philosopher, has given who has specialized in these fine-tuning arguments. He imagines your being dragged in front of a firing squad of one hundred trained marksman all with rifles aimed at your heart to be executed. You hear the command given: ready, aim, fire! And you hear the deafening roar the guns. Then you observe that you're still alive – that all of the one hundred marksmen missed! While you would be perfectly justified in saying, I shouldn't be surprised that I don't observe that I'm dead, because after all, if you were dead you couldn't observe it; you should nevertheless be extremely surprised that you do observe that you are alive in view of the enormous improbability of the one hundred marksmen all missing! In exactly the same way with respect to the universe, we shouldn't be surprised that we don't observe conditions of the universe incompatible with our existence because if they were incompatible we couldn't be here to observe it. But it doesn't in any way follow from that that we shouldn't be surprised that we do observe initial conditions of the universe which are compatible with our existence in view of the enormous improbability involved. So this argument that is given by these Anthropic theorizers is simply a fallacious argument. It's logically invalid, and it's been recognized as such today by the majority of scientists who are working on this problem.

KEVIN HARRIS: Just to further this illustration. If I were to be before this firing squad of a hundred trained marksmen, I heard the roar of the guns, and I took my blindfold off, and I was still alive, I would smell a conspiracy at this point.

DR. CRAIG: Exactly. You would say they all missed on purpose and that the whole thing was a setup engineered by someone for some reason. That would be a design inference.

KEVIN HARRIS: That's what we think about the universe. There seems to be a conspiracy here.

DR. CRAIG: Yeah, there is a conspiracy of these initial conditions being all finely tuned against . . . I mean improbability that is so great that it's humanly incomprehensible. And to infer that this is not the result of chance but of design is an eminently rational conclusion to draw.

KEVIN HARRIS: Dr. Craig, could one of the objections to this be the old monkey at the typewriter illustration? In other words, if the universe were eternal then eventually you're going to get this kind of fine-tuning just like if you have a monkey at a typewriter for a long enough period of time eventually he would type Hamlet.

DR. CRAIG: See, this is the thing about these finely tuned conditions that makes that response inappropriate. These conditions are initial conditions. They are present in the Big Bang itself, and therefore these numbers and quantities cannot be explained by any kind of evolution because they are initial conditions that are present right at the very beginning of the universe and therefore are not subject to cosmic evolution or any other kind of prior scientific explanation. It has to be either just brute accident that the Big Bang when it blew the universe into existence happened to be by chance alone fine-tuned to an incomprehensible precision for the existence of intelligent life. Or you've got to say that this is somehow physically necessary – that the universe could not have existed unless it were finely tuned in this way. Or else you've got to say the reason the universe appears to be fine-tuned is because it was fine-tuned. There is an intelligence which designed and brought the universe into being.

KEVIN HARRIS: There's a movement among science that tends to reflect this, and it's called the intelligent design movement. Are they considering these finely tuned aspects of the initial conditions?

DR. CRAIG: They are, or at least some of their members are. Many more are concerned with this additional layer of design that we talked about just a moment ago, namely, the complexity of biological organisms or the origin of life itself. These are just additional layers of improbability that are layered on top of the initial fine-tuning of the universe. But some of the intelligent design theorists, for example Robin Collins notably, is working on (or rather are working on) the question of the fine-tuning and how that itself points to an intelligent designer of the cosmos. Then the improbability that is layered on top of that by the origin of life and the evolution of biological complexity only adds more force to the argument.

KEVIN HARRIS: Dr. Craig, as we wrap up today, say something to those Christians who may be a little disturbed at the prospect of a very old universe, one perhaps twelve to fourteen billion years old.

DR. CRAIG: Well, I would say two things. First of all, I would say that the account in Genesis does not need to be taken to represent a six-day, consecutive 24-hour creation week that occurred ten to twenty thousand years ago. Historically this is not the way most Jewish rabbis or Christian church fathers interpreted that passage. So I think it's wholly compatible with the ages of the universe that the Big Bang theory postulates. But secondly, even if you are someone who believes the universe has been created only ten to twenty thousand years ago, this material is still valuable to you because you can say to your secular friend, Even on your own theory the universe has not existed forever. The universe still has to be exquisitely fine-tuned for the existence and evolution of intelligent life, and therefore even on your own theory you should believe in the existence of a transcendent Creator and Designer of the cosmos.[1]

 

[1]          Total Running Time: 11:23 (Copyright © 2007 William Lane Craig)