 Hi, I'm Peter Adamson and you're listening to the History of Philosophy podcast, brought to you with the support of King's College London and the LMU in Munich. Online at www.historyofphilosophy.com. Today's episode, Somebody's Perfect, Anselm's Ontological Argument. I was planning a vacation recently and heard about this amazing island. It lies in the most temperate region of the ocean and is always pleasantly warm and sunny, untouched by hurricanes or monsoons. The beaches are a pearly white, made of sand so fine that lying on them is said to be like sprawling on a silken blanket. A gentle breeze wafts the scent of hibiscus and coconut through the air, except for one particular area frequented by people who don't like the smell of hibiscus and coconut. Here, it instead smells like freshly brewed coffee. No one is quite sure why. As for the islanders, they are without exception cheerful and wealthy, yet take delight in satisfying the whims of visitors, plying them with exotic cocktails and succulent food and arranging nightly showings of Buster Keaton movies with live accompaniment by the world's leading pianists. It sounded pretty good, and I was just about to book my travel arrangements when I found out that this otherwise perfect island has one serious flaw. It doesn't exist. That's the last time I take vacation advice from my sister. In fact, my non-existent sister is not the first to imagine such a perfect island, an island which could not possibly be improved apart from its unfortunate non-existence. It appears in a famous objection made by a monk named Gaunilo to a proof for the existence of God devised by Anselm of Canterbury. When even the objection to an argument is famous, you can guess that the argument itself must be pretty well known, and indeed Anselm's so-called ontological argument for God's existence is probably the single most famous philosophical contribution by any medieval philosopher. It has provoked critiques, starting with Gaunilo in Anselm's own lifetime and subsequently from such leading philosophers as Thomas Aquinas and Immanuel Kant. It has also inspired later arguments for God. Proofs with the same general strategy, usually spelled out in much more rigorous fashion, have been offered for instance by Descartes, Gödel, and Alvin Plantinga. It's standard for historians of philosophy, like me, to complain that Anselm's argument is usually taken out of context. Students are typically asked to read only the few brief paragraphs where the proof is set out, ignoring the rest of the treatise in which the proof appears, Anselm's Proslogion, to say nothing of his previous and closely related work, the Monologion. And, as we'll see in this episode, it does help in understanding Anselm's argument to look at these texts in their entirety as well as his response to the critique of Gaunilo. But to some extent, Anselm is himself to blame for the fact that people focus on the proof to the exclusion of the rest of the Proslogion. It comes at the start of the treatise and provides the foundation for all that follows, so the whole project stands or falls on the success of this strategy. Indeed, in the prologue, Anselm tells us that he wants to base his account of God on one single powerful pattern of reasoning. This will be a departure from the approach of the Monologion, which offered several independent proofs of God's existence, among other things, in an attempt to capture the nature of God insofar as is possible for the human mind. What the two texts have in common is that their arguments are intended to be convincing even for an atheist, such as the fool of the biblical Psalms who, This fool is explicitly invoked at the start of the ontological argument. The idea is that Anselm's proof could bring even this person to see that God must exist. That same sort of ambition can already be found in the Monologion. It begins by asserting that the arguments to come should persuade any rational person, even one who has never heard of God or Christianity. This is a bold claim, given that Anselm is going to go on to argue not just for God's existence, but for specifically Christian doctrines like the Trinity, purely on the basis of rational argumentation. Yet, Anselm is far from dismissing the importance of revelation, or belief through religious faith. His motto is the Augustinian slogan, Credo ut Intelligam – I believe in order to understand – something we see, for instance, in the dialogues on free will we talked about last time. At one point, the student character in those dialogues is confronted with a puzzling theological doctrine and says, I believe this, but I want to understand it. The ontological argument and the rest of the reasoning offered in both the Monologion and the Proslogion are not intended to replace faith with rational proof, as if this were something better, but to provide an insight into what exactly the person of faith already believes. It's important to bear this in mind when looking at Anselm's various proofs for God's existence. It helps draw our attention to a feature of all these proofs which is that they are not only about establishing that God does in fact exist, rather they are part of a larger project of understanding what God is like. The formula at the center of the ontological argument describes God as that than which nothing greater can be conceived. From this formula, Anselm wants to infer not just that God exists, and indeed necessarily exists, but also that He is good, powerful, just, eternal, and so on. In this respect, his proof is not unlike one offered several decades earlier, but half a world away, in Central Asia. The great Muslim philosopher Avicenna also devised an argument for a necessarily existing God. Much as Anselm tries to extract a wide range of traditional attributes of God from the formula that than which nothing greater can be conceived, Avicenna wanted to show that a necessary existent must have such features as uniqueness, immateriality, power, and goodness. This is what Anselm has in mind when he says that his Proslogion is going to provide one single argument that will yield all the results achieved through separate arguments in the monologuion. The first of those has a very Platonist flavor. It observes that there must be some cause for the goodness we find in the things around us. Although goodness manifests itself in different ways, goodness itself should have the same meaning in each case. Otherwise, we would have no unified idea of goodness, but instead lots of different ideas that are misleadingly expressed by the same word. We need therefore to suppose that there is a cause of goodness, which is the source of this shared nature that we find in all good things. As the cause of all goodness, this source will itself be good, indeed the most good and great of all things, namely God. This may not look like a very persuasive argument, but it is no worse, if also no better, than the reasoning given to support the theory of forms in Plato's dialogues. Of course, what Anselm is describing here is not going to be just an abstract form of goodness, but rather an entity that is maximally good. The same result is achieved through a different argument in the monologuion, which begins from the humble observation that some things are better than others. Anselm's example is that humans are better by nature than horses, which are better by nature than trees. Can we imagine that the scale of goodness just keeps going indefinitely, like a scale of heat with no highest temperature? In that case, there would have to be an infinity of natures in the universe, since every nature has some nature that is better than it. But this strikes Anselm as patently absurd. So again, we can postulate a highest nature, which is maximally good, and this, of course, is God. Already here in the monologuion, Anselm reaches the same conclusion he will be heading for when he devises his ontological argument a few years later. If God is maximally good, as these proofs claim to show, then he must have every property that belongs to a maximally good thing. What properties will these be? Well, any property, such that it is better or greater, to have it than not to have it. In contemporary philosophy of religion, these are sometimes called the great-making properties. For instance, it is better to be powerful than to be weak, so God, being maximally good, will be powerful. In fact, he will be all-powerful, since it is better to have each individual power than not to have it, so he must have them all. He will also be just, merciful, wise, eternal, and so on, since again it is better to have these properties than not to have them. So far, the reasoning we've been following seems to suggest that we can grasp God's nature quite easily. We just think of every property, such that having it is better than not having it, and describe it to God. Job done. But Anselm cautions us against such a straightforward interpretation of what he is doing. He may not be a negative theologian on a par with the pseudo-Dionysius or Eriugina, but he does deny that we can grasp God's nature fully with the finite resources of the human mind. In fact, you can even establish this using the same logic of great-making properties. Anselm would think it obviously better to be beyond the grasp of human language and thought than to be graspable by humankind. So God, being maximally good, must be ineffable. How can we nonetheless ascribe all those other great-making properties to him? In the monologuion, Anselm gives a traditional response, that we are only using the likenesses of created things to describe him. But he already glimpses a more innovative answer, God is understood not as the best thing, or as greater than everything else, but as that than which nothing is better or greater. As Anselm will later point out in his replies to Gagnilo's criticism, this is a subtle but crucial difference. The ontological argument would not work if we just said that God is greater than anything else. We need to say that God is that than which nothing greater could exist, or be conceived. This also leaves it open for Anselm to admit that God outstrips our understanding. If he were the greatest thing we can conceive, then obviously we would be in a position to conceive of him. But if he is that than which nothing greater can be conceived, he may to some extent lie beyond our grasp. Still, we do grasp him to some extent, just as we must to some extent grasp anything when we call it ineffable or inconceivable. Suppose I say, five trillion is an inconceivably large number. Even as I tell you that you can't conceive of this number, I am telling you something about it, namely that it lies beyond your comprehension. The Proslogion is devoted entirely to working out the implications of this idea that God is that than which nothing greater can be conceived. From this idea, one can infer God's goodness, eternity, omnipotence, and so on. By the way, this part of Anselm's project struck his critic Gaunilo as unproblematic. It was only the argument at the very beginning that failed to convince him. Why? Because the famous argument tries to infer the very existence of God from this formula, and this application of Anselm's new trick struck Gaunilo as too tricky by half. Yet the argument is elegantly, or perhaps infuriatingly, simple. Invoking the atheistic fool from the Psalms quotation, Anselm says that even though the fool does not believe in God, he will surely be able to understand the formula, that is, he can follow what the words mean. To put it the way that Anselm does, this thing than which nothing greater can be conceived at least exists in the fool's mind, even if it does not exist in reality. But now, Anselm can show the fool that his atheistic position makes no sense. It is contradictory to suppose that God doesn't exist in reality but only in the mind if we understand God as that than which nothing greater can be conceived. This is because if God existed only in the mind, it would be easy to conceive of things better than him. Notably, we could conceive of him as existing in reality and not just in the mind. As Anselm puts the point, if that than which a greater cannot be thought exists in the mind alone, this same that than which a greater cannot be thought is that than which a greater can be thought, but this is obviously impossible. This is the same sort of reasoning used later in the Proslogion to prove that God is, for instance, eternal. It belongs to the very nature of that than which a greater cannot be thought to be eternal because if it were not eternal, we could think of something better by thinking of something that is eternal. In the same way, it is implied by the formula that the thing in question must exist because if it didn't exist, we could conceive of something better than it. The fool must therefore admit that God exists on pain of contradicting himself. Like Mr. T., Gounilo pitied the fool and argued on his behalf that Anselm's argument did not work. He devised a number of objections including his famous island analogy. Consider, says Gounilo, an island than which no better island can be conceived. If we suppose that this island didn't exist in reality, we would fall into the same contradiction because a non-existing island clearly isn't one than which no better island can be conceived. Therefore, such an island in fact exists. This is a powerful objection. If you can use a pattern of reasoning to prove something false, then you know there is something wrong with that pattern of reasoning. Since the version of the argument with the island apparently works just like Anselm's argument but yields a false conclusion, we can infer that Anselm's proof must be a failure. Notice though that Gounilo's island objection shows only that the reasoning used by Anselm must have gone astray somewhere without actually diagnosing his mistake. How might Anselm respond? We don't have to guess because we actually have Anselm's reply to Gounilo's criticisms, which is a very helpful document for understanding how Anselm thought his proof was supposed to work in the first place. Obviously, to meet the objection, he has to show that it makes a difference that we are being asked to think about an island as opposed to God. The difference is that existence belongs to the very nature of that than which nothing greater can be conceived, whereas existence cannot belong to the very nature of an island. As the American military proved when they were testing atom bombs in the Pacific Ocean, an island is the sort of thing that can go out of existence. So, if we find ourselves entertaining the idea of an island that cannot possibly fail to exist, then what we are entertaining makes no sense. By contrast, that than which nothing greater can be conceived is going to be something whose very nature guarantees its real existence. Anselm had already made this point back in the Proslogion. That than which nothing greater can be conceived is not merely something that exists, it is something that must exist. It exists necessarily, because it cannot even be conceived as not existing. I think that this is a good response to the island objection. But that doesn't mean the proof works. It's been subject to many other criticisms. Apart from the island objection mounted by Gaunilo, the most well-known response is probably the one made by Kant, who argued that Anselm was wrong to take existence as a property on a par with features like justice, goodness, or eternity. Existence is not just one more property that I can think of a thing as having. This is why it struck an absurd note at the beginning of this episode, when I treated the existence or non-existence of an island as a feature on a par with the whiteness of its sands or the scent of its breezes. According to Kant, when I think of something, I am conceiving of it as having a range of properties. Its existence is simply the realization or instantiation in the world of something that has those properties. Whether this same objection can be applied to the idea of necessary existence, though, seems to me to be an open question. Even if existence is not a property, like justice or eternity, the trait of existing necessarily might be. But I think we don't need to deny that existence or necessary existence is a property in order to defeat Anselm's argument. If the way I've set it out does capture Anselm's line of reasoning accurately, then it has a more fundamental flaw. For me to say that necessary existence is included in the very nature of a thing is not yet to assert that the thing exists. Rather, it is to say that if it did exist, then it would, by its very nature, exist necessarily. This seems not only right, but a genuine insight on Anselm's part, and one strikingly parallel to what Avicenna had been doing just a few years previously. Anselm saw that if God is to be that in which nothing greater can be conceived, he would be the sort of thing that cannot fail to exist. But this, as far as I can see, just means that God cannot exist contingently. In other words, he can't exist while possibly not existing. From this, it doesn't follow that God in fact exists. Gaunilo made this same point in a passage which should be remembered alongside his much more frequently noticed island objection. He wrote, So there you have it. Anselm's famous proof and a few possible responses to it. Obviously, this comes very far from exhausting the topic, but then too, concentrating on the ontological argument comes far from exhausting the topic of Anselm and his philosophy. This is why I began last time by looking at other aspects of his thought. He was a pivotal figure in medieval philosophy, not so much for the proof as for the whole approach he took, an approach where faith seeks understanding through rational arguments that presuppose none of the beliefs that are held by faith. This will set the tone for the further developments of early scholasticism in the thought of Peter Abelard and other thinkers of the 12th century. Such is Anselm's importance, in fact, that I'd like to spend one more episode with him. So, don't be a fool, join me for an interview than which no greater can be conceived, as I talk to Anselm expert Eileen Sweeney here on The History of Philosophy Without Any Gaps.