Does God Exist?William Lane Craig
In this article Dr. Craig sets forth eight reasons why he thinks God exists.
On April 8, 1966, Time magazine carried a lead story for which the cover was completely black except for three words emblazoned in bright, red letters against the dark background: “IS GOD DEAD?” The story described the so-called ‘Death of God’ movement then current in American theology. But, to paraphrase Mark Twain, it seemed that the news of God’s demise was “greatly exaggerated.” For at the same time that theologians were writing God’s obituary, a new generation of young philosophers was re-discovering His vitality.
Back in the 1940s and ’50s it was widely believed among philosophers that any talk about God is meaningless, since it is not verifiable by the five senses. The collapse of this Verificationism was perhaps the most important philosophical event of the twentieth century. Its downfall meant a resurgence of metaphysics, along with other traditional problems of philosophy which Verificationism had suppressed. Accompanying this resurgence came something altogether unanticipated: a renaissance of Christian philosophy.
The turning point probably came in 1967 with the publication of Alvin Plantinga’s God and Other Minds, which applied the tools of analytic philosophy to questions in the philosophy of religion with an unprecedented rigor and creativity. In Plantinga’s train has followed a host of Christian philosophers, writing in professional journals and participating in professional conferences and publishing with the finest academic presses. The face of Anglo-American philosophy has been transformed as a result. Atheism, although perhaps still the dominant viewpoint in Western universities, is a philosophy in retreat. In a recent article, University of Western Michigan philosopher Quentin Smith laments what he calls “the desecularization of academia that evolved in philosophy departments since the late 1960s.” (‘The Metaphilosophy of Naturalism’, Philo, Vol 4, #2, at philoonline.org). Complaining of naturalists’ passivity in the face of the wave of “intelligent and talented theists entering academia today,” Smith concludes, “God is not ‘dead’ in academia; he returned to life in the late 1960s and is now alive and well in his last academic stronghold, philosophy departments.”
The renaissance of Christian philosophy has been accompanied by a resurgence of interest in natural theology – that branch of theology which seeks to prove God’s existence without appeal to the resources of authoritative divine revelation – for instance, through philosophical argument. All of the traditional philosophical arguments for God’s existence, such as the cosmological, teleological, moral, and ontological arguments, not to mention creative, new arguments, find intelligent and articulate defenders on the contemporary philosophical scene.
But what about the so-called ‘New Atheism’ exemplified by Richard Dawkins, Sam Harris, and Christopher Hitchens? Doesn’t it herald a reversal of this trend? Not really. As is evident from the authors it interacts with – or rather, doesn’t interact with – the New Atheism is, in fact, a pop-cultural phenomenon lacking in intellectual muscle and blissfully ignorant of the revolution that has taken place in Anglo-American philosophy. It tends to reflect the scientism of a bygone generation, rather than the contemporary intellectual scene.
Eight Reasons in Support of God’s Existence
I believe that God’s existence best explains a wide range of the data of human experience. Let me briefly mention eight such cases.
1. God is the best explanation why anything at all exists.
Suppose you were hiking through the forest and came upon a ball lying on the ground. You would naturally wonder how it came to be there. If your hiking buddy said to you, “Forget about it! It just exists!” you would think he was either joking or just wanted you to keep moving. No one would take seriously the idea that the ball just exists without any explanation. Now notice than merely increasing the size of the ball until it becomes coextensive with the universe does nothing to either provide, or remove the need for, an explanation of its existence.
So what is the explanation of the existence of the universe (by ‘the universe’ I mean all of spacetime reality)? The explanation of the universe can lie only in a transcendent reality beyond it – beyond space and time – the existence of which transcendent reality is metaphysically necessary (otherwise its existence would also need explaining). Now there is only one way I can think of to get a contingent entity like the universe from a necessarily existing cause, and that is if the cause is an agent who can freely choose to create the contingent reality. It therefore follows that the best explanation of the existence of the contingent universe is a transcendent personal being – which is what everybody means by ‘God’.
We can summarize this reasoning as follows:
1. Every contingent thing has an explanation of its existence.
2. If the universe has an explanation of its existence, that explanation is a transcendent, personal being.
3. The universe is a contingent thing.
4. Therefore, the universe has an explanation of its existence.
5. Therefore, the explanation of the universe is a transcendent, personal being.
– which is what everybody means by ‘God’.
2. God is the best explanation of the origin of the universe.
We have pretty strong evidence that the universe has not existed eternally into the past, but had a beginning a finite time ago. In 2003, the mathematician Arvind Borde, and physicists Alan Guth and Alexander Vilenkin were able to prove that any universe which has, on average, been expanding throughout its history cannot be infinite in the past, but must have a past spacetime boundary (i.e., a beginning). What makes their proof so powerful is that it holds so long as time and causality hold, regardless of the physical description of the very early universe. Because we don’t yet have a quantum theory of gravity, we can’t yet provide a physical description of the first split-second of the universe; but the Borde-Guth-Vilenkin theorem is independent of one’s theory of gravitation. For instance, their theorem implies that the quantum vacuum state which may have characterized the early universe cannot have existed eternally into the past, but must itself have had a beginning. Even if our universe is just a tiny part of a so-called ‘multiverse’, composed of many universes, their theorem requires that the multiverse itself must have had a beginning.
Of course, highly speculative physical scenarios, such as loop quantum gravity models, string models, even closed timelike curves, have been proposed to try to avoid this absolute beginning. These models are fraught with problems, but the bottom line is that none of these theories, even if true, succeeds in restoring an eternal past for the universe. Last year, at a conference in Cambridge celebrating the seventieth birthday of Stephen Hawking, Vilenkin delivered a paper entitled ‘Did the Universe Have a Beginning?’, which surveyed current cosmology with respect to that question. He argued that “none of these scenarios can actually be past-eternal.” Specifically, Vilenkin closed the door on three models attempting to avert the implication of his theorem: eternal inflation, a cyclic universe, and an ‘emergent’ universe which exists for eternity as a static seed before expanding. Vilenkin concluded, “All the evidence we have says that the universe had a beginning.”
But then the inevitable question arises: Why did the universe come into being? What brought the universe into existence? There must have been a transcendent cause which brought the universe into being – a cause outside the universe itself.
We can summarize this argument thus far as follows:
1. The universe began to exist.
2. If the universe began to exist, then the universe has a transcendent cause.
3. Therefore, the universe has a transcendent cause.
By the very nature of the case, that cause of the physical universe must be an immaterial (i.e., non-physical) being. Now there are only two types of things that could possibly fit that description: either an abstract object like a number, or an unembodied mind/consciousness. But abstract objects don’t stand in causal relations to physical things. The number 7, for example, has no effect on anything. Therefore the cause of the universe is an unembodied mind. Thus again we are brought, not merely to a transcendent cause of the universe, but to its Personal Creator.
3. God is the best explanation of the applicability of mathematics to the physical world.
Philosophers and scientists have puzzled over what physicist Eugene Wigner called “the unreasonable effectiveness of mathematics.” How is it that a mathematical theorist like Peter Higgs can sit down at his desk and, by pouring over mathematical equations, predict the existence of a fundamental particle which, thirty years later, after investing millions of dollars and thousands of man-hours, experimentalists are finally able to detect? Mathematics is the language of nature. But how is this to be explained? If mathematical objects like numbers and mathematical theorems are abstract entities causally isolated from the physical universe, then the applicability of mathematics is, in the words of philosopher of mathematics Mary Leng, “a happy coincidence.” On the other hand, if mathematical objects are just useful fictions, how is it that nature is written in the language of these fictions? The naturalist has no explanation for the uncanny applicability of mathematics to the physical world. By contrast, the theist has a ready explanation: When God created the physical universe He designed it in terms of the mathematical structure which He had in mind.
We can summarize this argument as follows:
1. If God did not exist, the applicability of mathematics would be just a happy coincidence.
2. The applicability of mathematics is not just a happy coincidence.
3. Therefore, God exists.
4. God is the best explanation of the fine-tuning of the universe for intelligent life.
In recent decades scientists have been stunned by the discovery that the initial conditions of the Big Bang were fine-tuned for the existence of intelligent life with a precision and delicacy that literally defy human comprehension. This fine-tuning is of two sorts. First, when the laws of nature are expressed as equations, you find appearing in them certain constants, such as the gravitational constant. The values of these constants are independent of the laws of nature. Second, in addition to these constants, there are certain arbitrary quantities which define the initial conditions on which the laws of nature operate – for example, the amount of entropy (disorder) in the universe. Now these constants and quantities fall into an extraordinarily narrow range of life-permitting values. Were these constants or quantities to be altered by less than a hair’s breadth, the life-permitting balance of nature would be destroyed, and life would not exist.
There are three live explanatory options for this extraordinary fine-tuning: physical necessity, chance, or design.
Physical necessity is not, however, a plausible explanation, because the finely-tuned constants and quantities are independent of the laws of nature. Therefore, they are not physically necessary.
So could this fine-tuning be due to chance? The problem with this explanation is that the odds of all the constants and quantities’ randomly falling into the incomprehensibly narrow life-permitting range are just so infinitesimal that they cannot be reasonably accepted. Therefore the proponents of the chance explanation have been forced to postulate the existence of a ‘World Ensemble’ of other universes, preferably infinite in number and randomly ordered, so that life-permitting universes like ours would appear by chance somewhere in the Ensemble. Not only is this hypothesis, to borrow Richard Dawkins’ phrase, “an unparsimonious extravagance,” it faces an insuperable objection. By far, the most probable observable universes in a World Ensemble would be worlds in which a single brain fluctuated into existence out of the vacuum and observed its otherwise empty world. So, if our world were just a random member of the World Ensemble, by all probability we ought to be having observations like that. Since we don’t, that strongly disconfirms the World Ensemble hypothesis. So chance is also not a good explanation. Thus,
1. The fine-tuning of the universe is due to either physical necessity, chance, or design.
2. The fine-tuning of the universe is not due to physical necessity or chance.
3. Therefore, the fine-tuning of the universe is due to design.
Thus, the fine-tuning of the universe constitutes evidence for a cosmic Designer.
5. God is the best explanation of intentional states of consciousness.
Philosophers are puzzled by states of intentionality. Intentionality is the property of being about something or of something. It signifies the object-directedness of our thoughts. For example, I can think about my summer vacation, or I can think of my wife. No physical object has intentionality in this sense. A chair or a stone or a glob of tissue like the brain is not about or of something else. Only mental states or states of consciousness are about other things. In The Atheist’s Guide to Reality: Enjoying Life without Illusions (2011), the materialist Alex Rosenberg recognizes this fact, and concludes that for atheists, there really are no intentional states. Rosenberg boldly claims that we never really think about anything. But this seems incredible. Obviously, I am thinking about Rosenberg’s argument – and so are you! This seems to me to be a reductio ad absurdum of his atheism. By contrast, for theists, because God is a mind, it’s hardly surprising that there should be other, finite minds, with intentional states. Thus intentional states fit comfortably into a theistic worldview.
So we may argue:
1. If God did not exist, intentional states of consciousness would not exist.
2. But intentional states of consciousness do exist.
3. Therefore, God exists.
6. God is the best explanation of objective moral values and duties.
In our experience we apprehend moral values and duties which impose themselves as objectively binding and true. For example, we recognize that it’s wrong to walk into an elementary school with an automatic weapon and shoot little boys and girls and their teachers. On a naturalistic view, however, there is nothing really wrong with this: moral values are just the subjective by-products of biological evolution and social conditioning, and have no objective validity.
Alex Rosenberg is brutally honest about the implications of his atheism here too. He declares, “there is no such thing as… morally right or wrong.” (The Atheist’s Guide to Reality, p.145); “Individual human life is meaningless… and without ultimate moral value.” (p.17); “We need to face the fact that nihilism is true.” (p.95). By contrast, the theist grounds objective moral values in God, and our moral duties in His commands. The theist thus has the explanatory resources to ground objective moral values and duties which the atheist lacks.
Hence we may argue:
1. Objective moral values and duties exist.
2. But if God did not exist, objective moral values and duties would not exist.
3. Therefore, God exists.
7. The very possibility of God’s existence implies that God exists.
In order to understand this argument, you need to understand what philosophers mean by ‘possible worlds’. A possible world is just a way the world might have been. It is a description of a possible reality. So a possible world is not a planet or a universe or any kind of concrete object, it is a world-description. The actual world is the description that is true. Other possible worlds are descriptions that are not in fact true but which might have been true. To say that something exists in some possible world is to say that there is some consistent description of reality which includes that entity. To say that something exists in every possible world means that no matter which description is true, that entity will be included in the description. For example, unicorns do not in fact exist, but there are some possible worlds in which unicorns exist. On the other hand, many mathematicians think that numbers exist in every possible world.
Now with that in mind, consider the ontological argument, which was discovered in the year 1011 by the monk Anselm of Canterbury. God, Anselm observes, is by definition the greatest being conceivable. If you could conceive of anything greater than God, then that would be God. Thus, God is the greatest conceivable being – a maximally great being. So what would such a being be like? He would be all-powerful, all-knowing, and all-good, and He would exist in every logically possible world. A being which lacked any of those properties would not be maximally great: we could conceive of something greater – a being which did have all these properties.
But this implies that if God’s existence is even possible, then God must exist. For if a maximally great being exists in any possible world, He exists in all of them. That’s part of what it means to be maximally great – to be all-powerful, all-knowing, and all-good in every logically possible world. So if God’s existence is even possible, then He exists in every logically possible world – and therefore in the actual world.
We can summarize this argument as follows:
1. It is possible that a maximally great being (God) exists.
2. If it is possible that a maximally great being exists, then a maximally great being exists in some possible world.
3. If a maximally great being exists in some possible world, then it exists in every possible world.
4. If a maximally great being exists in every possible world, then it exists in the actual world.
5. Therefore, a maximally great being exists in the actual world.
6. Therefore, a maximally great being exists.
7. Therefore, God exists.
It might surprise you to learn that steps 2-7 of this argument are relatively uncontroversial. Most philosophers would agree that if God’s existence is even possible, then He must exist.
So the question is, is God’s existence possible? Well, what do you think? The atheist has to maintain that it’s impossible that God exists. That is, he has to maintain that the concept of God is logically incoherent, like the concept of a married bachelor or a round square. The problem is that the concept of God just doesn’t appear to be incoherent in that way. The idea of a being who is all-powerful, all-knowing, and all-good in every possible world seems perfectly coherent. Moreover, as we’ve seen, there are other arguments for God’s existence which at least suggest that it’s possible that God exists. So I’ll just leave it with you. Do you think, as I do, that it’s at least possible that God exists? If so, then it follows logically that He does exist.
8. God can be personally known and experienced.
This isn’t really an argument for God’s existence; rather it’s the claim that you can know God exists wholly apart from arguments, by personally experiencing him. Philosophers call beliefs grasped in this way ‘properly basic beliefs’. They aren’t based on some other beliefs; rather they’re part of the foundation of a person’s system of beliefs. Other properly basic beliefs would be the belief in the reality of the past or the existence of the external world. When you think about it, neither of these beliefs can be proved by argument. How could you prove that the world was not created five minutes ago with built-in appearances of age like food in our stomachs from the breakfasts we never really ate and memory traces in our brains of events we never really experienced? How could you prove that you are not a brain in a vat of chemicals being stimulated with electrodes by some mad scientist to believe that you are reading this article? We don’t base such beliefs on argument; rather they’re part of the foundations of our system of beliefs.
But although these sorts of beliefs are basic for us, that doesn’t mean that they’re arbitrary. Rather they’re grounded in the sense that they’re formed in the context of certain experiences. In the experiential context of seeing and feeling and hearing things, I naturally form the belief that there are certain physical objects which I am sensing. Thus, my basic beliefs are not arbitrary, but appropriately grounded in experience. There may be no way to prove such beliefs, and yet it’s perfectly rational to hold them. Such beliefs are thus not merely basic, but properly basic. In the same way, belief in God is for those who seek Him a properly basic belief grounded in their experience of God.
Now if this is so, then there’s a danger that philosophical arguments for God could actually distract your attention from God Himself. The Bible promises, “Draw near to God and he will draw near to you.” (James 4:8) We mustn’t so concentrate on the external arguments that we fail to hear the inner voice of God speaking to our hearts. For those who listen, God becomes a personal reality in their lives.
In summary, we’ve seen eight respects in which God provides a better account of the world than naturalism: God is the best explanation of
1. Why anything at all exists.
2. The origin of the universe.
3. The applicability of mathematics to the physical world.
4. The fine-tuning of the universe for intelligent life.
5. Intentional states of consciousness.
6. Objective moral values and duties.
7. The very possibility of God’s existence implies that God exists.
8. God can be personally experienced and known.