Q&A: Gideon Rosen

Gideon Rosen has taught in the philosophy department at the University since 1993. His area of philosophic thought deals mainly with morals and ethics.

'Prince' senior writer Kathy Li sat down with Rosen to discuss his latest work and future plans.

'Prince': What is your particular area of interest?

Rosen: My original areas of interest were some reasonably obscure technical things in philosophy of mathematics, metaphysics and epistemology. I'm still interested in those things and I still work on them, but in the past couple of years, I've been mostly teaching and working in moral philosophy. My plan over the next couple of years is to concentrate on moral philosophy and the philosophy of law.

P: Does that ask things like "What is a good person"?

R: Ethics deals with all kinds of questions: what's a good person, what's a just state, how should we act, which is not exactly the same question as what's a good person.

My work is concerned with the ethics of praise, blame, punishment and the whole range of responses we have to violations of moral norms. So, suppose you just take a common-sensical position about what's right and wrong, common sense doesn't have a worked-out moral theory, but common sense knows exactly, in most cases, which acts are right and which acts are wrong. You shouldn't steal, you shouldn't kill and so on.

The question then arises, what do you do with people who transgress the norms? Common sense and law both have views about this, but they're not fully explicit. So sometimes we blame people and punish people for violations of these norms, but sometimes we don't. Sometimes we allow people to make excuses. Excuses are fact, considerations that give us reason not to punish or blame people who have done something wrong. So what are the excuses and why are those the excuses?

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P: You mean things like psychological defenses in law?

R: Yes. So, the law recognizes extreme insanity as an excuse. Morality and moral common sense make allowances for all kinds of psychological problems: You shouldn't blame him, he was depressed; You shouldn't blame him, he was having a rough day; You shouldn't blame him, he just broke up with his girlfriend. Why do we allow those excuses to mitigate blame or even block it altogether?

Not just for little things, but for some quite serious things. How should the insanity defense, or the mental disturbance defense, in morality, not in the law, be understood, what are the rules that govern it, so on and so forth?

That's a huge question and one that I'm quite interested in.

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P: Can you describe the philosophy of math?

R: Sure. Mathematics is historically the most certain and least problematic area of human knowledge. If you go back thousands of years, there was very little science to speak of, very little psychology, or sociology, or anthropology. These disciplines didn't exist. Nothing that they knew then would count as knowledge by our standards.

But ancient mathematics is still clearly mathematics. There's always been mathematics. Especially during the period of the ancient Greeks, mathematics was a fully worked out science already. So mathematics is supposed to be totally unproblematic. If you look at how modern mathematics is represented, what do mathematicians do? They prove theories from axioms. They assume some things and they derive consequences from them. The tool for deriving consequences from axioms is logic.

And logic is quite well understood now. No one, or very few people, seriously doubt that if you know something and you can derive something else from it by logical means, then you know the thing you've derived.

So the real question about mathematical knowledge is the status of the axioms. How do we know them? Because, the axioms by definition aren't things that you prove. If you look at the axioms for most of modern mathematics, some of them look obvious, but some of them don't.

For example, one of the axioms that underlies almost all modern mathematics is the assumption that there are infinitely many mathematical objects. That's not something you prove, that's something you assume. How do you know that? Mathematics can look like a kind of natural science, like geography or biology, without any experiments at all. You make some assumptions about these objects and from those assumptions, you can do all these wonderful things, but how do you know the assumptions to be true?

A lot of people say you don't, that's the kind of thing mathematicians will sometimes say, "The axioms are just assumed, we don't say they're true, we don't assume they're true; all we're interested in is what follows from them." But if that's all you're interested in, it's not clear why you should be allowed to use the things you prove when you're doing physics or engineering, or anything else where mathematics is brought to bear on applications to the real world.

It's hard to believe that the mathematics we use isn't true, but there's still the question of how we know the assumptions to be true. It's an ancient question, but it does not have a general solution. No one knows exactly what the right thing to say is.

P: What kind of questions does epistemology ask?

R: In epistemology, we ask similar questions, not just about mathematical knowledge, but about knowledge much more generally. Epistemology has traditionally been preoccupied by skepticism about the external world: How do I know that I'm not dreaming now, How do I know I'm having a conversation with a real person, How do I know that you're not a hallucination, that sort of thing.

Those questions don't interest me all that much. But there are areas where it is quite hard to see how we know what we know, what reasons we have for believing what we believe.

Mathematics is one of those areas. Another area is ethics. How do we know the moral propositions we think we know: that it's wrong to steal, that you shouldn't humiliate people for fun? We don't test these things by performing experiments. And it's not because we can just look and see. Someone who doesn't believe these things, some psychopath who thinks it's perfectly okay to humiliate people for fun, will look at an instance of humiliation with his eyes, and his eyes will be functioning properly and he'll see just what I see, but he'll reach a different conclusion.

Morality is problematic because its principles aren't confirmed by experiment or by observation and they're not obvious and uncontroversial like the principles of mathematics either. So one question of epistemology is what's the source of moral knowledge? Another question is what's the source or basis of our knowledge of what's possible? Because, that's another thing you can't confirm by doing experiments.

Well, you can in a sense. If you want to know whether it's possible to build a spaceship, well, you can try and if you succeed, then you know it's possible. But there're all sorts of things we believe to be possible that we don't know on that basis. We haven't done them yet.

It's possible that there should have been intelligent reptiles. There aren't any, there never have been, there probably never will be, but the very notion isn't impossible. It is impossible that there should be a square circle or a triangle with eight sides. Some things are possible, some things are impossible and sometimes we can know that without doing experiments. So that's another area where the source of our knowledge is kind of mysterious.

P: I took your Introduction to Metaphysics and Epistemology class last year. How do you teach these complicated theories to introductory students?

R: Certain questions in philosophy are immediately gripping as soon as someone points them out to you. So, those are the questions I focus on in my intro course. It's very easy to find it interesting, whether there's a God, how we can know whether there's a God. And once you point to someone the problem about how we know whether the external world exists, the kind of problem that's raised really vividly by "The Matrix" and other science fiction movies these days, these are immediately gripping.

The questions that I actually work on are questions that are very hard to motivate beginning students. You have to spend some time in philosophy before you see why these things are gripping. So, we don't do those in an intro course. But it's never enough just to point out an interesting question. The subject is only gripping to the extent that students see that it's possible to make a kind of progress on these questions.

Now the progress isn't like the progress in mathematics where you settle questions once and for all. The progress that you make, that you try to illustrate, is seeing more deeply into what the question is and what the possible solutions are by considering inarticulate, inchoate, half-formulated solutions, trying to make them fully explicit and then seeing whether they can be criticized. Once you've done that for a while, you may not have the answer to your question but you see much more deeply what the possible answers are. And, that's the value that philosophy has for most undergraduates.

It's not that they're going to be professional philosophers who go on to write papers on the subject. You get something out of it, to the extent that you see that rigorous, disciplined thinking about abstract questions can actually lead you to understand the questions more clearly. So that's what I try to bring out in that class.

P: I've heard that you're taking a year off to go to New York University's law school to study. What will you be studying there?

R: I have this terrific fellowship founded by the Mellon Foundation. These fellowships are designed for scholars who want to get some training in a field that they've never studied before, the sort of field that you can't just teach yourself.

My undergraduate teaching has been devoted to this course called Freedom and Responsibility, which is an upper level philosophy course about responsibility in law and ethics. So I've been using legal materials in this class, teaching about the insanity defense for example and teaching myself. But I figured because my research is now closely related too, I figured that I would spend some time trying to learn the subject properly.

So I'm going to go to NYU. I'm going to take a good chunk of the first year law curriculum: tort law, criminal law, property contracts. I mean, it's not just this stuff. Law is hugely fascinating from a philosophical point of view.

It's a lot like philosophy in certain ways because a legal theory can't just be a list of rules. It's not satisfactory and not useful for judges and lawyers and people who might find themselves in court, unless they're principles which explain the underlying basis for the rules.

This attempt to justify particular rules by reference to more general principles is what moral philosophy is all about also. So there are these formal similarities and the fact is, in law, the details matter quite a lot. So what you find in law is incredible detail, rigorous attempts to articulate general principles governing rules of conduct. So that's always interesting from the point of view of a philosopher. I want to learn enough of the law to be in position to work on that kind of thing.

P: I was going to ask you if ever started to doubt reality, thinking about metaphysics and its questioning of the external world, but it doesn't seem that you do.

R: No, I think that kind of skepticism is an interesting intellectual puzzle, but it's never . . . when Descartes first describes it, Descartes actually describes himself getting dizzy when he realizes the power of the argument he's constructed. I think everyone should have that experience once (laughs), but if you don't recover pretty quickly, that's a bad sign.

No, this part of philosophy is aimed not at proving something that we all are invincibly convinced of already. It's aimed at understanding the rational status of that condition. Hume was really right about this: The human mind is constructed in such a way that serious doubts about the existence of reality just can't be sustained. You'll always snap out of it. But that doesn't mean it's rational or reasonable, it just means that it's going to happen. So you do that part of philosophy because you want to know how rational you're being in taking the existence of the external world for granted.

I do get worried about some things. Not that, but the stuff in ethics that I've been doing. I mean, one thing we take for granted, not as grand as the existence of the external world, but one thing we take for granted is that people are generally responsible for what they do. So that when somebody steps on your foot or when somebody steals your purse or when somebody commits a crime or someone starts an illegal war, it's perfectly legitimate to be angry at them, to resent them, and if it's violation of some explicit legal rule, to punish them for it and to express our anger and resentment by actually causing them to suffer.

People disagree about hard cases, but hardly anyone doubts that people really do deserve this kind of treatment sometimes for the wrong they do.

My thinking about responsibility has actually gotten me to doubt this. If you look closely enough at the detailed structure of any case of wrongdoing, you try to reconstruct explicitly what the agent's motives were, what the agent's reflection or reasoning was like, how he saw the situation at the time and you ask yourself whether it was his fault that he saw things as he did, whether it was his fault that he reasoned as he did. You start pressing this kind of question and your capacity to blame people for what they do erodes.

Most people have this experience and then snap out of it and they find themselves perfectly capable of going on and getting as angry as they were before. I've actually, over the past couple of years, found myself changing my practical attitudes towards other people on the basis of philosophical reflection.

I think that people may sometimes be responsible for what they do, but it's very hard to know when they are. And if it's hard to know when they are, then there's something to be said for giving everyone a benefit of the doubt. That doesn't mean their acts are right or that there shouldn't be legal rules against them. It means that a certain kind of program directed at people who do the wrong thing isn't obviously appropriate even when everyone assumes it is. So I've actually changed my view about that. I've found myself much easier on other people, much easier on myself, as a result of having thought through this kind of skeptical argument.

P: Do you think that Western thought today, like science and math, heavily influences philosophy? It seems that eastern philosophy is slightly different from this sort of western philosophical questioning.

R: Eastern philosophy is a huge sprawling thing. Its tradition is as old as the tradition of western philosophy and it's as complex. Eastern philosophy has developed the mystical strand in western philosophy to a much greater degree than western philosophy ever did. That really is a different subject. Because the mystical tradition is a tradition which is suspicious of reason and clearheadedness and explicitness as a source of knowledge. The Western tradition really does privilege that, but there are elements in eastern philosophy all over the place which privilege it also. I don't know very much about it.

My sense is that it's a different vocabulary, it would take ages to learn it and because it's a very different vocabulary, the problems it raises are slightly different. But there's a huge amount of overlap. And there are a very, very small number of scholars trying to make connections between the eastern and western traditions. The fact is, eastern philosophy is rarely taught in philosophy departments in the United States. It is more often taught or studied in religion departments or in East Asian departments. But that doesn't mean there aren't deep connections.

It's sort of an accident of sociology that what we call philosophy derives very directly from the Greek tradition. And what people taught was the philosophy they learned in school, and no one ever learned eastern philosophy in school until very, very recently in this tradition.