The Logic of Paradox

“Form is emptiness, and emptiness is form.” Every day, millions of Buddhists chant these paradoxical words from the Heart Sutra in order to cut through conceptually mediated perception and transcend the confines of logical thought. By dwelling on paradox, by returning again and again to contradiction, we hope to gain insight into a reality larger and deeper than our limited ideas about the world.

Though paradox is often treated as a means of moving beyond thought, Buddhists have been thinking about paradox for millennia. Philosophers like Nagarjuna, Dogen, and Kitaro Nishida have developed complex metaphysical systems and innovative logical machinery that enable us to come to grips with contradiction and speak meaningfully about it, to the extent that that is possible.

Graham Priest, Distinguished Professor of Philosophy at CUNY Graduate Center, has spent much of his career thinking about the relationship between logic and paradox. In addition to pathbreaking work developing new forms of logic equipped to handle contradictions, Priest has published widely on the history of paradox in Buddhist thought. Tricycle spoke with Priest about his path from formal logic to Buddhist philosophy, what it means to accept contradiction, and the techniques Buddhists throughout history have used to speak about paradox.

This interview has been edited for length and clarity.

You were trained as a mathematician. How did you become interested in Buddhism? To answer that, I’d first have to answer a prior question: How did I become interested in philosophy? My doctorate was in mathematical logic, but I was studying bits of mathematics with fairly close connections to philosophy. By the time I finished my doctorate, I realized that philosophy was a lot more fun than mathematics, so I decided I wanted to be a philosopher. For reasons I still don’t understand, a philosophy department gave me a job teaching the philosophy of science.

So I became a professional philosopher, but I didn’t really know any philosophy. I had to teach myself, and have had a blast doing so ever since. But after about twenty-five years of studying Western philosophy, I met Jay Garfield (who’s now an old friend) at a conference just as he was finishing his translation of Nagarjuna’s Fundamental Wisdom of the Middle Way, and I was finishing my book Beyond the Limits of Thought. We started chatting, and I realized that I was ignorant of half of the world’s philosophy. It was a bit of a shock, so I decided I had better start educating myself in that too.

Why Buddhism? Well, it’s partly a historical accident, because it’s what Jay happened to study. 

But it’s not entirely accidental, because, of all the Asian traditions, Buddhism is the one that I find I have the most sympathy with. I’m not a Buddhist; I don’t practice meditation. But I am a sort of fellow traveler philosophically. 

Why this sympathy with Buddhism? I guess because I’m enough of a philosopher to believe things if, and only if, there are good reasons for taking them to be true. I think that Buddhism gets some very fundamental things right. The Buddhist analysis of the human condition (the “four noble truths”) seems to get matters pretty much right. When it comes to metaphysics, I’m persuaded by the arguments in the Madhyamaka school, that everything is empty. That is, everything is what it is only because of its relation to other things. We live in a deeply interconnected world.

You’re known as a defender of paradox. What is a paradox? “Paradox” comes from the Greek words para and doxa. Doxa means belief. Para has many meanings, but the relevant one here is “beyond.” So etymologically, paradox means “beyond belief.” A paradox is an argument that produces something literally beyond belief, something incredible, or at least, hard to believe. And paradoxes are many in philosophy, East and West. 

What’s an example of a Buddhist paradox? Well, the notion of emptiness steers close to the wind of paradox in many ways. For example, commenting on the central Madhyamaka claim that all things are empty (sunya), Nagarjuna says in his Vigrahavyavartani, quoting the Astasahasrika Prajnaparamita Sutra: All things have one nature, and that is no nature—an obvious contradiction. This is (perhaps!) behind the famous first koan of the Gateless Gate. When someone asked Joshu, ‘Does a dog have buddha-nature?,’ the answer would seem to be yes and no. Joshu’s reply: Mu, meaning no, nothing, or I reject the question. Go figure.

How do philosophers respond to paradoxes? When you encounter a paradox, you have a choice. The first option is to accept the conclusion of the paradoxical argument as correct, even though it’s initially incredible. The other is to find something wrong with the argument so that you don’t have to accept the conclusion. For most paradoxes in the Western tradition, people have chosen this second option. If you can’t accept contradictions, then you’ve got to find something wrong with an argument that ends in a contradiction. For many paradoxes, that’s the right approach. But for others, this strategy doesn’t work, which means you have to adopt the first option and accept a contradiction. Of course, that is highly unorthodox in Western philosophy, though less so in Eastern philosophy. 

What does it mean to say that some contradictions are true? What does it mean for logic? What does it mean for rationality? For metaphysics? This opens a Pandora’s box of questions that I’ve spent much of my academic career exploring. Initially, I thought it was crazy to think that some contradictions could be true. For ten years, I kept waiting for someone in the back of an audience to put their hand up and show me that it was crazy. But it never happened. And so I came to think that it wasn’t actually crazy to accept some contradictions. Now, I’m pretty convinced that it’s sometimes the right move.

Do all Buddhist philosophers accept contradictions? Not at all. The first time I ever went to India, it was to go to the Tibetan University in Sarnath, the town where the Buddha is said to have first taught after achieving enlightenment. I was there with Jay Garfield, and one thing we did was to give a talk on Nagarjuna to monks from several different Tibetan traditions. Everything was going swimmingly until we said that Nagarjuna believed that contradictions could be true. The reaction was amazing. Half of the monks said, “Yeah, of course, that’s obvious!” and the other half said, “No, no—that can’t be right!” So there is a lot of tension even within Indo-Tibetan Buddhism about contradictions. The Chinese Buddhist tradition, on the other hand, is highly influenced by Daoism, which is replete with paradoxes. So Chinese Buddhists have been less scared of accepting paradoxical conclusions than Western (and some Indo-Tibetan) philosophers.

Why do you think Buddhists have been more open to paradox? This answer is going to be contentious, but I think the basic reason is that there was never any Aristotle in the Asian traditions. Some Western philosophers before Aristotle held that some contradictions are true. In the Metaphysics, Aristotle tried to prove them wrong by arguing for what later became known as the Principle of Non-Contradiction. The arguments he gives there, however, are terrible—and this isn’t just my view; it’s the view of many modern Aristotle scholars!

Still, Aristotle was so influential in later Western philosophy that his view became orthodox. Now, in contemporary philosophy, nearly everything that Aristotle endorsed has been rejected, or at least problematized, except his arguments against contradiction. I think that the Principle of Non-Contradiction is the last bastion of Aristotelianism. Since there was no one with the same authority who defended the Principle in India or China, there wasn’t the same orthodoxy to fight against. That’s why Buddhist philosophers have been more willing to accept contradictions.

But the idea that a contradiction can be true strikes most as extremely counterintuitive. Most who? Most Western-trained philosophers, maybe. There are now a number of studies where researchers go out onto the street and ask people philosophical questions, and they’ve shown that many people (in the West) are quite prepared to accept some contradictions.

For example, let’s say it’s pouring rain, and then it peters off. There’s a borderline moment where it’s not clear whether or not it’s still raining, and a lot of people are OK with saying that it’s both raining and not raining, or that it’s neither raining nor not raining—in fact, saying both, which is itself a contradiction! Many people don’t have a problem with describing these situations using contradictory terms.

So when philosophers say “we think,” we should remember that usually they mean “me and my mates who’ve been trained in the same way.” It doesn’t mean they’re wrong, it just means that we have to treat this hegemonic move—saying “we think” or “everybody thinks”—carefully. 

Wittgenstein said that philosophical issues arise because of an “inadequate diet of examples.” People are bound to agree that contradictions can’t be true if they think only of run-of-the-mill things like “catching a bus and missing it,” or “being in China and not being in China.” But if you take less mundane things concerning infinity, self-reference, or the ultimate nature of reality—things outside one’s ordinary experience—true contradictions may start to look more plausible. Maybe the “common sense” view about contradictions being impossible is just the result of insufficient imagination.  

Can you speak a bit about what you call the “paradox of ineffability”? In every philosophical tradition I know, there are philosophers who think that some things are beyond the bounds of language, transcending our ability to describe and conceptualize. That doesn’t mean you can’t experience those things; it just means you can’t characterize what it is that you’re experiencing.

If you’re arguing that something is ineffable, you’ve got to conceptualize it, because arguments use concepts. So there’s a paradox here: I’m arguing that something is ineffable, and in doing so, I’m describing and conceptualizing it. 

But the trouble is that those philosophers don’t just say that some things are ineffable; they give arguments as to why they are ineffable. Of course, if you’re arguing that something is ineffable, you’ve got to conceptualize it, because arguments use concepts. So there’s a paradox here: I’m arguing that something is ineffable, and in doing so, I’m describing and conceptualizing it. 

Do you see anything unique in how Buddhist philosophers have responded to the paradox? In the West, the general thought is that you’ve got to find some way out of it. The standard technique is this: When you meet a contradiction, draw a distinction. Some Eastern philosophers, including a number of the later Buddhist philosophers, have also tried to get out of the paradox we have just looked at by drawing a distinction. There’s a move you find, for example, in the work of the Tibetan philosophers Tsongkhapa (c. 1357–1419) and Gorampa (c. 1429–1489), whose ideas were important in the development of the Gelug and Sakya schools. Tsongkhapa and Gorampa say, “Ultimate reality is ineffable. So to talk about the ineffable, you’ve got to draw a distinction between the nominal ultimate and the real ultimate. The real ultimate is ineffable, and the nominal ultimate is a kind of linguistic approximation that we can describe. So whenever we talk about the ultimate, we’re just talking about the nominal ultimate, which is effable.” This allows you to avoid talking about ultimate reality and contradicting yourself. 

But you might respond, “Pardon me? Whenever one talks about the ultimate, one is talking about the nominal ultimate, and that is effable.” “Yes.”  “So when you said that the real ultimate is ineffable, haven’t you just contradicted yourself?”—“Oh, jeez, yes!” 

Although there are certainly attempts to get out of the paradox of ineffability in the Buddhist tradition, by no means have all Buddhist philosophers done this. This is especially clear in China. There’s a whole tradition of paradox that runs through the Daoist-Buddhist tradition, where philosophers are aware of this paradox of ineffability and show no desire to get out of it. So the bottom line: Trying to get rid of the paradox of ineffability has been a standard move in the West, and though some Buddhist philosophers have tried to do the same, there isn’t the same drive to do so.  

Many Buddhist philosophers—Nagarjuna, for example—have relied on a framework called the catuskoti (“four corners”) to speak about contradiction. What is the catuskoti, and how has it been helpful to Buddhist philosophers? The catuskoti is a principle to the effect that, given any claim, there are four possibilities: that it is true (and true only), false (and false only), both, or neither. Note that something that falls into the third koti—being so and not so—is a true contradiction. The catuskoti predates the Buddha, but is to be found in some of the sutras, though it is not doing heavy work there. It does very heavy work in the philosophy of Nagarjuna, his school (Madhyamaka), and all the subsequent Mahayana schools that this influences (which is all of them). The role it plays in Nagarjuna and subsequent developments is complex and, I think it’s fair to say, often contentious. But that it provides a framework for what is going on in these traditions is uncontentious.

If we accept contradictions, does that have any implications for Buddhist practice? Well, part of the answer is banal. The first of the eightfold path is right view—understand the world aright. If so, you’d better understand what is true and what is not; and if some of the truths are of the form it is and it isn’t so-and-so, then you’d better understand that.

In much more concrete ways, I think one might look at the actions one sometimes takes. Life is complex, and it is often the case that for some things there are good reasons you ought to do them, and good reasons it’s not the case that you ought to do them. (For example, telling the truth and compassion would sometimes seem to conflict.) Sometimes one set of reasons clearly outweighs the other. But sometimes this is not the case. (As an extreme case, think of Sophie’s Choice, where a concentration camp guard forces Sophie to choose which of her two children will be sent to the gas chambers.) In such cases it would seem that whatever you do will be both right and wrong. In particular, whatever you do you will be doing something wrong. One might well see this as a form of dukkha. But then, that there are going to be such things is the first noble truth. And, one might suppose, the second and third noble truths, teach that one should not cling to the fact that one has done something wrong.

If we accepted Joshu’s answer, “mu,” in the koan you described earlier, what impact would that paradox have on the practitioner’s life? Erm . . . mu.