(This post is part 5 of the series entitled “Contesting Christianity.” Please see the index for the other posts in this series.)
As far as my experience has shown, philosophical arguments do not play a large role in the life of most believers. Most people seem to come to be a Christian either from growing up into a Christian family or through an intense emotional experience of “conversion”. Nevertheless, philosophical arguments for the existence of God and/or the truth of Christianity have a rich historical tradition, from Thomas Aquinas and Augustine of Hippo to Descartes and Kant. And while many philosophers have conceded that these arguments are ultimately unsuccessful, they still do have their supporters even today. So I’d like to take some time to examine a few of the most common philosophical arguments for God.
The Cosmological Argument
While many Christians would likely be unfamiliar with the term “cosmological argument,” this is actually used quite commonly in informal settings. Anyone who has asked the question, “If God doesn’t exist, then how did everything get here?” has employed the cosmological argument in a very basic sense. The general idea is that the universe must have had something which caused it to come into existence, and this “First Cause” must have set things in motion. Such an argument has had numerous reformulations over the years, beginning with Plato and Aristotle and made more concrete with Thomas Aquinas’ five proofs for the existence of God. After serious criticisms of the argument by David Hume and Immanuel Kant, it fell out of favour, but has since been revived in modified forms, with the most prominent form being the Kalam cosmological argument (KCA) defended by William Lane Craig. As this is the form that one would be most likely to hear today, I will spend the rest of this section talking about this version of the argument.
Kalam Cosmological Argument
In the most basic form put forward by Craig, the argument goes as follows:
- Whatever begins to exist has a cause.
- The universe began to exist.
- Therefore, the universe has a cause.
This is a deductive argument, meaning that if the premises (1 and 2) are true, the conclusion (3) must necessarily also be true. Craig usually goes on to say that this cause must also be an uncaused (because it is the first cause), immaterial (because it created matter), timeless (because it created time), and changeless (because it exists outside of time) being. It must also be a personal being that can freely choose to act, or else the universe could not have been created at a specific point. This all sounds a lot like what we typically call “God”. Thus, Craig concludes that the cause of the universe is God.
In support of his first premise, Craig typically appeals to intuition. Of all the things we see come into existence, each and every one of them has a cause. So, as his reasoning goes, it simply makes sense that such a thing is a general rule of all things which come into existence. For the second premise, however, Craig spends more effort supporting this with data. As far as I am aware, he accepts Big Bang cosmology (or at least holds it to be the current scientific consensus), and so he appeals to the large amounts of data supporting this theory. In addition, he makes appeal to concepts surrounding infinite sets, and the differences between potential infinities (like something you would encounter in math equations) and actual infinities (like an infinite series of time). I won’t get into much detail about this, but in essence, he argues that actual infinites cannot exist in reality, and so time must have a starting point.
So what are the problems with this argument? I’d like to start with the second premise, since that’s comparatively simpler to deal with. First, while Big Bang cosmology enjoys enormous support from scientific evidence, it is important to remember that scientific theories may always be overturned in light of new evidence. Thus it is a possibility that the second premise may lose its support from science in the future. Indeed, there are already alternative models of the universe which would not require it to have a beginning. Cyclical models of alternating big bangs and big crunches exist, and there are other models which do not posit the big bang as the absolute beginning of space and time. There are also people who argue that actual infinites to exist—in other words, that there could have been an infinite series of events before this current moment. However, I have little expertise in this area to really make a judgment of whether those arguments are sound or not. So for the time being, I will accept Craig’s second premise.
But now let’s go back and deal with the first premise. For starters, scientists note that things come into existence without a cause all the time on the subatomic level. For example, in radioactive decay, an alpha, beta, or gamma particle begins to exist spontaneously; there is no actual cause of it coming to exist. Also, unlike what you learned in basic high school science class, quantum physics describes the bizarre behaviour of electrons, which pop in and out of existence seemingly at random.
Even if one sets those aside as peculiar cases, however, one needs to ask the question of what it means to “begin to exist.” I’ll use a few examples to illustrate why the common sense notion of “begin to exist” is problematic for this argument. Tables come into existence. We can watch a carpenter form a table that, the day before, did not exist anywhere in the world. Trees come into existence as they pop out of the ground, where previously there was no tree. Houses come into existence when construction workers build them. However, while in one sense we can say these things “come into existence”, in another very important sense, these objects are merely rearrangements of matter. The table was fashioned out of wood, which was previously a tree. The tree was previously a seed, plus water and nutrients from the soil which are rearranged. The house was previously wood and metal and concrete, which all had their own previous forms as well. None of these things “came into existence” in the sense of atoms and molecules appearing where there previously were none. In every single case where our intuition tells us that something “began to exist,” it was merely rearrangement of existing stuff. This is unlike the universe itself, which must have come into being where previously there was absolutely nothing. So in a very important sense, we have zero examples of anything beginning to exist. And if we have no examples, we have nothing with which to support the first premise at all. And of course, premises which cannot be supported are worthless premises.
I think that what I’ve laid out above is pretty damning to the KCA. I don’t think that it is at all reasonable to rely on “intuition” when dealing with the existence of all space and time. For myself, I can barely comprehend the vastness of the province I live in, let alone the Earth, the Milky Way galaxy, or the mind-bogglingly large universe itself. Our intuitions work very well for medium-sized objects we are used to dealing with in our everyday lives, like people and animals and trees and cars and buildings. But as quantum mechanics has shown us, our intuitions break down when dealing with tiny particles; it seems at least plausible that they might also break down when dealing with vastly huge objects as well. But as a final point, I think it is important to point out that a successful cosmological argument would only get an individual to a “First Cause.” It at most presents a being (perhaps not even a being) that set the universe in motion. That’s it. It hardly gets us anywhere close to a personal, loving being, or to the Christian God that is outlined in the Bible.
The Ontological Argument
Unlike the cosmological argument, I doubt anyone has ever used the ontological argument in an informal setting—it remains a purely philosophical exercise. The ontological argument was first presented by Anselm of Canterbury, and has been supported in various forms by other philosophers since. René Descartes, Gottfried Leibniz, and Alvin Plantinga have also produced well-known forms of the argument. Despite this, it has received pretty extensive criticism from many philosophers. I will present the argument as given by Anselm, since this is an easier form to understand. Descartes’ and Leibniz’ versions would require me to provide much more context to the argument with little gain, and Plantinga’s version relies on “possible worlds,” which is simply too complex of a topic for this article. Anyone interested in these other versions can take a look at the link at the bottom of the page.
Anselm’s argument is a little tricky to piece together from his writings, but essentially it goes something like this (source):
- It is true by definition that God is a being than which none greater can be conceived.
- God exists as an idea in the mind.
- A being that exists as an idea in the mind and in reality is greater than a being that exists only as an idea in the mind.
- Thus, if God exists only as an idea in the mind, then we can imagine something that is greater than God (that is, one that also exists in reality).
- But, by definition, we cannot imagine something that is greater than God.
- Therefore, God exists.
You might think that at first glance, this argument seems to work flawlessly. It is a deductive argument, and all the premises seem to be true, so that would mean that the conclusion of God’s existence is necessarily true as well. Nonetheless, I suspect that you, as I did when I first read it, might have a funny feeling that something about this is not right. It seems just a bit too easy. And if you have that feeling, you are in agreement with many other philosophers on the matter.
Criticism of the Ontological Argument
The first objection to Anselm’s argument was actually put forward by a monk named Gaunilo of Marmoutier, a contemporary of Anselm. He pointed out that “God” could essentially be replaced by any other concept, with absurd results. Gaunilo demonstrated with the “greatest conceivable island.” It would, of course, be greater for an island to exist in reality instead of only in the mind, and as such, the greatest conceivable island must exist in reality. But clearly this is bizarre. David Hume later pointed out that it was absurd to try to conclude the existence of an object or being through reason alone, without any reliance on evidence or observation.
Perhaps are more important criticism was made by Immanuel Kant. He pointed out that “existence” is not a property of the concept of something, but rather a description of the concept’s instantiation in the real world. For example, while “having three sides” is a property of triangles, “existing” is not. One could still have a concept of triangles even if no triangles existed in the real world. (Similarly, I can have a concept of unicorns even though none exist in the real world.) Existence is merely a statement about whether there is an instance of the concept in the world. In other words, there is no difference between the concept of a triangle and the concept of a really existing triangle. The reason that triangles exist is that there are real objects that correspond to the concept of triangles. In the same way, then, existence cannot be a property of God, but rather a description of God’s instantiation in the real world. One cannot simply conjure up a God merely by thinking about God.
Deriving from Kant’s objection, it is also the case that existence is not a “great-making property.” There is nothing inherently better about an object that exists compared to one that does not exist. While we might like it more if the greatest conceivable water slide actually existed, it wouldn’t therefore be a “better” water slide. If that were the case, then it must likewise be said that a real Auschwitz concentration camp is “better” than an imaginary Auschwitz concentration camp existing in the mind alone. This doesn’t seem to work properly. Thus, the “greatest conceivable being” is no greater for existing in the real world than existing in the mind alone.
The Moral Argument
The moral argument seems to be another one that many Christians often use informally. Although I don’t see it get mentioned as often as the two arguments above, it has been put forward by many people. Because of this, it has numerous forms, and I cannot possibly hope to deal with all of them here. However, they are generally similar to each other, so I will use William Lane Craig’s version as illustrative of them all.
Craig outlines his argument as follows:
- If God does not exist, objective moral values and duties do not exist.
- Objective moral values and duties do exist.
- Therefore, God exists.
As you can see, the argument is fairly simple and straightforward. This deductive argument essentially states that moral values and duties are dependent on God for their existence. Craig supports premise 1 by pointing out that such a statement is supported and argued for even by many atheists. And premise 2 is usually supported through intuition: “We all know that objective moral values exist!”
Criticism of the Moral Argument
Both premises can be challenged here. To start with the first premise, while it is true that some atheists believe such a statement, (a) there is a wide variety of opinions about the grounds of morality among both believers and non-believers, and (b) whether or not atheists support the statement really says nothing about its truth. It is not at all clear that objective moral values are dependent on God, and various moral philosophers argue that (objective) moral values are brute facts of the universe, or products of evolutionary development, or results of a hypothetical “social contract,” and more. In addition, philosophy uses the term “objective” in a very specific sense: as “mind-independent.” In other words, something objective must be the case regardless of any entity’s thoughts, decisions, or judgments. If one is claiming that moral values are dependent on God for their content, it can become very strange to say that such values are “objective.” They rely on the judgments of an entity: God. This makes them, by definition, subjective.
In order to avoid this problem, some (including Craig) define this dependency in a different way. Craig instead argues that moral values are rooted in the character of God as a perfect being; however, he still claims that moral duties are formed through God’s commands, and the commands of a being definitely fall into the subjective realm. Moreover, it becomes difficult to see how God’s character being a certain way really has any ramifications of what our moral values become. If God were hateful instead of loving, would that make hate a moral value? If God’s character meant that he really liked the colour blue, would that make blue a moral “good”? Just because a perfect being exists with a certain character, this doesn’t seem to entail any specific characteristics of morality. He may make the universe a certain way because of his character, but this would still seem to fall under the “subjective” realm, unless one is willing to argue that God himself does not have free will.1
The second premise seems just as contentious as the first. Craig’s support for it, as I mentioned, is that we simply intuitively know that some things are right or wrong. But this begins to get tricky to support. An examination of cultural differences reveals many things that are viewed as immoral or wrong in one culture, but permissible or okay in another culture. Cannibalism is one example. People growing up in cultures that practice cannibalism simply do not have any intuitions about the wrongness of eating other human beings. It doesn’t seem that they are calloused towards such things, or that they are willfully ignoring their intuitions, but rather that they simply do not believe there is anything wrong with it. Similar things can be found for a whole host of other behaviours. In short, it seems that at least many of the moral values we find “intuitive” are culturally-specific. This doesn’t mean that they don’t exist objectively, but it does argue against the efficacy of our moral intuitions.
Of course, philosophers throughout history have found other ways to ground objective moral facts. Typically, they use reason and logic to uncover these things. If such things can be found using arguments and reason, however, this tends to undercut the idea that moral values are dependent on God. It seems, rather, that they are dependent on reason. So traditional forms of moral reasoning present in philosophy generally can’t be used to support this moral argument.
So it seems that without any support for the second premise, and with difficulties in supporting the first premise, that this argument is unsuccessful. It remains an interesting debate in the philosophical literature, but the challenge especially of grounding the second premise on anything other than intuitions makes this a difficult argument to sell.
We have taken a look at three of the most common philosophical arguments for God. Although philosophers go into much more detail concerning these arguments, I have tried to do my best to summarize the arguments and then provide critiques of them. It seems that these arguments, while an excellent attempt, are fraught with difficulties that philosophers and theologians throughout centuries of time have not been able to adequately resolve. Moreover, even if these arguments were successful, they would get us nowhere close to the God of Christianity, but merely to the so-called “God of the philosophers,” a vague being who, at most, set things in motion. To try to translate this into the Christian God would take much more than these arguments have to offer.
- A Bug in William Lane Craig’s Kalam Cosmological Argument – Another critique of the KCA, but one focusing on “actual infinites,” by Jeffrey Allen.
- Cosmological Argument, Ontological Arguments, Moral Arguments – For the more amibitious, here’s a pretty comprehensive summary of the three theistic arguments by the Stanford Encyclopedia of Philosophy.
- Ontological Argument – Another great summary, but this one by the Internet Encyclopedia of Philosophy.
- Morality Requires God…or Does It? – Coming at the moral argument from a different angle, including the Euthyphro dilemma.
- If he didn’t, then he wouldn’t have a true choice in the matter of how moral values were set, so one might be able to argue that they were objective. [↩]