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John Treat: Do you recall what awakened your interest in philosophy? What questions first animated you?

John Post: Well, perhaps naively and romantically, I was always curious about what I thought of as "ultimate things," and about how we and the world might form a coherent whole--about what meanings might be found there, and what relations those might have to one's personal life. In college I quickly realized--was made to realize--that you cannot think responsibly or even creatively about those things without certain tools. But it was not until fairly late in college that I began to realize those tools were to be found in philosophy. They included logic, ethics, epistemology, history of philosophy, and much else. Some of these, I soon found, could become quite technical. In graduate school and later, I had to guard against becoming so fascinated with the tools and the technicalities that I lost sight of the questions--the larger and more humane aims--with which I had started.

My first book, The Faces of Existence, was an attempt to put a lot of these things together as best I could at the time. It seems to me that in order to break out of the ruts that philosophers have been in for at least a half century, probably much more, we still need close, careful thinking on the one hand, and a lot of daring, imagination, and creativity on the other. One of my favorite aphorisms is from Stravinsky's little book, The Poetics of Music (the Norton Lectures, 1936). He says, "To enjoy to the full the conquests of daring, we must demand that it operate in a pitiless light." That captures for me the dialectic between, on the one hand, imagination, daring, originality, emotion, and on the other, the necessary close, careful, rigorous scrutiny of even the best of our thinking. I think that such scrutiny is necessary in order to bring all these somehow into balance, to result, one hopes, in something worth leaving behind. That is what I tried to do in that book. It was like rolling dice. I took some comfort also in it being a bit like mountain climbing, which I used to do a lot of. Many of the same emotions are in play there, the same risks, but at the end of it, even if you do not quite make your summit, you at least have the satisfaction of knowing that you tried, which a lot of others may not have done.

Anyway, the questions that first interested me were not very clear. They were, as is the case with any young person I suppose, vague and general and bumbling and romantic. But in various forms they are still very much with me and have driven much of my work even when it seems--even when it is--very abstract and technical. Most of the work has some larger point--I like to think all of it does--although in a given paper I am not always very explicit about just how it does.

For example, the stuff in philosophical logic on the semantic paradoxes--including a new one I found called "the Possible Liar"--I always knew had implications for larger issues to do with rationality, the nature and limits of logic and reason, and accounts of meaning, reference, and semantics generally.

Treat: What was the title of your dissertation? What would you say about it now?

Post: It was called "The Logic of Presupposition." It was not bad--but it was not as good as the committee thought.

Treat: What were your earliest sustained professional interests?

Post: Theories of rationality, philosophical logic, philosophy of education.

Treat: What about your current research concerns?

Post: Epistemology, meta-ethics, metaphysics, environmental ethics, and more. I am at an age and stage where a lot of stuff is coming together, and branching out as well. One paper that will appear in January is entitled "The Foundationalism in Irrealism, and the Immorality." The irrealism I have in mind, which ironically owes a lot to Descartes, is held by many philosophers who congratulate themselves for overcoming Descartes' insidious influence. Yet they turn out to be foundationalists despite themselves--what I call structural foundationalists.

This structural foundationalism underlies the view of logic and language according to which even the most basic principles of our logic and features of our language are ultimately conventions; they are merely the products of the grammatical structure of our language, so that "The world appears logical to us because we have made it logical," as Nietzsche puts it. Such views are driven by varieties of neo-Kantianism, typically linguisticizations and historicizations of Kant. As I have tried to show, such views are based on a very shaky presupposition--one that may seem a minor, technical point--namely, that all of the relevant forms of inference are transitive. I trace the presupposition back to Descartes and the sixteenth-century background that influenced him so deeply. Its roots are in Aristotle's regress argument for the foundational structure of reason giving.

So we need to be careful that we do not buy too quickly into a strand of Western thought according to which none of the grammatical or logical features of language are there because of "the way the world is"--the world in which we evolved. Treat: Is this relationship a matter of language "mapping" onto the world?

Post: There are many ways of "mapping" onto the world. After all, you can have very many different kinds of maps of the same terrain, and they can all be equally good, given the purposes for which we make them. They can use very different coordinate systems, or none at all, and yet they are deeply compatible. There is a theorem to that effect in C. A. Hooker's book, A Realistic Theory of Science. Still, what we have to look at, in order to raise the kind of question I think you are raising, is whether it makes sense to say that they are all of the same terrain.

Treat: Are there not other ways in which our language relates to the world that are entirely accountable to what is there, but not in the sense of "mapping"? In other words, is "mapping" necessarily the appropriate way in which to conceive of the "word-world" relation?

Post: I would go further and say that there are lots of ways in which we speak, the point of which is not to "map" at all. Even in logic the matter of whether the point is to "map" depends on what logic is, which ideas about logic are right, and which parts of logic we are talking about. For example, there are "logics" that are so weird and deliberately removed from any conceivable application that, so far as they have a purpose at all, it is pretty clearly not to "map." Such a logic may in fact be just a set of interesting ideas that some people are pursuing rather as if they were mathematicians. It can be intrinsically fascinating to spell out the consequences of a few concepts or a few ideas about a certain sort of function or system.

Treat: Correct me if I have misunderstood, but I thought that a part of what you were saying was that the non-optionality of some of the features that such a person would be delineating is itself a consequence of this "mapping" relation between language and world.

Post: What I am suggesting is that those are parts of logic and ways of doing logic where there is not any significant non-optionality--where it is almost all optional.

Treat: Then my question, I suppose, is about the point at which you see the notion of mapping as becoming relevant in an epistemologically justificatory sense.

Post: One point, maybe the point at which it becomes relevant is when we ask whether we are thinking of logic as a kind of a priori, abstract discipline, or as an a posteriori, concrete discipline that is to bear certain relations to the world in which we evolved. If we approach logic in the latter spirit, we start asking the following sort of questions about, say, the law of non-contradiction: Why is it that all natural languages contain sentences that are subject-predicate in form and subject to negation, so that normally speakers would not say of the same item that it has both a property and one of its contraries? What is the best explanation of this apparently universal feature? Because of the sheer variety of cultures and kinds of understanding, it is hard to buy a neo-Kantian explanation--say an explanation to the effect that the law of non-contradiction is the creation of a constructive understanding--and it is especially hard to buy a linguisticized, historicized, cultural-relative version of such an explanation.

Treat: Do you see a problem of translation involved?

Post: What raises the characteristically skeptical or at least philosophical problem of translation are certain Indo-European philosophies--those that argue, rightly or, I think, quite wrongly--that there are deep problems in principle about translation. The argument on which these philosophies typically depend is one in which we are to assume that on some deep, philosophical level--whether categorical, conceptual, linguistic, infrastructural--no further argumentation or interpretation can be given, on pain of circularity or else infinite regress. When you puzzle through what is driving this assumption, you find--peering up at you from the bottom of the mug, to steal a phrase from J. L. Austin--the transitivity presupposition.

Thus many of the skeptical questions about translation are themselves the product, ironically, of some characteristically Indo-European philosophies and arguments, whether from Quine or Wittgenstein or Derrida. So that is where we should look, in the first instance, for the credentials about the suggestion that imputing non-contradiction to a non-Indo-European language or culture is just our projection. Then we should look to theories of meaning and translation that give the best positive accounts of these matters. When we do, we find Millikan's account, which implies that imputing non-contradiction to a non-Indo-European language or culture is hardly just our projection.

Treat: What are your other current concerns?

Post: I am reflecting more on ethics--not just meta-ethics but normative ethics. Throughout this century, each new departure in the philosophy of language--whether positivist, sprach-spielist, structuralist, post-structuralist, realist--has had a big impact on philosophers' ideas about the nature of normative judgments, whether these judgments can have truth values, and how to go about justifying or criticizing them. I think that recent teleo-functional accounts of meaning and reference--by Millikan and others--may likewise have large implications for our ideas about these matters. That is one of the things I am working on, and it bears significantly on some issues in environmental ethics that concern me.

Treat: And you are looking toward a book that will address some of those issues?

Post: Yes. There are some anticipations of it in earlier work: a few pages in Metaphysics in the sections dealing with value in chapter six. There is a bit more in papers I gave at conferences last year that have not been published yet.

Treat: Where else do you see your research in philosophy headed over the next few years? What do you hope to accomplish with your research?

Post: I am currently working on a book tentatively titled Properties of Supervenience: An Introduction with Applications. A number of the applications are to the philosophy of psychology. The book deals with some of the relations among explanation, non-reductive determination, mental causation, supervenience of the mental, and the nature of the evidence relative to such matters.

Treat: How would you characterize your relationship to philosophy now--both academic philosophy and, if one may speak this way, philosophy as such? Has that relationship changed over the years, and if so how?

Post: Certainly it has changed over the years. As in life in general, so in one's professional career, there are ages and stages. There is the insecurity and paranoia of graduate school, of trying to get a job and get established. To get published and get tenure. Those can be stressful years, but what comes later can be stressful too. And I have tended, in part because of those pressures, to write somewhat different things at different stages. Even when I was writing much the same kind of thing, or trying to, the effect was occasionally very different.

At times, philosophy has been an obsession. The last few months, though, have been a time to step back, regroup, and reflect. My mother died last April. Also, both our boys are grown now and I miss them very much. We bonded very closely and did a lot of things together.

Treat: Were they your climbing buddies?

Post: No, I never took my family climbing. I finally gave it up myself because I wanted my boys to grow up with a father.

Treat: How do you view the profession of philosophy? Do you see any limits or problems inherent in its professionalization, and if so, how would you characterize them?

Post: My relationship to academic philosophy is increasingly wary. It always has been to some extent. I think we philosophers, and many others, pay a terrible price for being shut up within this type of institution--colleges and universities. One part of that price is extreme sub-specialization. Another, related to it, is the tendency to play things very safe in order to get the degree, get a job, get promoted. By the time we get through a few years of this, we have been so socialized into a kind of caution that we are unfit as real thinkers, as thinkers with any real imagination, boldness, originality. It takes guts to do that, and a lot of us do not have that much courage.

Treat: I know that you have criticized Derrida for what I gather strikes you as a dismissive attitude toward Anglo-American philosophy. Certainly his exchange with Searle, for instance, looks from one perspective like mere dismissal and a refusal to engage.

Post: Some of it comes out in the exchange with Searle, but some predates it. I do think that Derrida's critique of Husserl on language and meaning is a brilliant, formidable piece of internal criticism. It is a reduction to absurdity of the Husserlian account. It is the Derridian dialectic that comes next that is very significant. It amounts to saying something like, "A Husserlian account of meaning will not do, therefore. . . ." and then we are given Derrida's alternative account. So in effect we are presented with a disjunctive syllogism: A or B; not A; therefore B. And a standard way to critique such an argument is to ask about that disjunctive premise: Why are we given only two choices? Even in the 1960s, there were alternative accounts. In the decades since then, a whole lot more has been going on in empirical linguistics, evolutionary semantics, and evolutionary linguistics--and I do not mean just Millikan's stuff. To my knowledge Derrida has not looked at it.

Treat: I have tended to think, perhaps erroneously, that his engagement with philosophy has been not so much an effort to propose alternative theories as to try to find a way to resist a bias toward a certain kind of theorizing, what one could call the "default mode" for philosophical discourse--to try to find a way to say, perhaps indirectly, that while theorizing has its place and its value, we seem to have fallen headlong into it, and cannot see our way out.

Post: Among other things he has a loaded understanding of theorizing. What he thinks of as theorizing is not the only thing that theorizing is. But in addition he has got a point. To paraphrase Mark Twain: "Abstinence from theorizing is all right so long as nobody gets hurt." We do have to be wary of being fragmented persons; we have got to be careful that we do not become obsessed with the theory at the expense of the phenomena and each other. But we have to balance that with legitimate concerns about how best to explain, so far as we can, the things we are interested in: ourselves and the world and our relation to it. It is understandable, and to a very great extent valuable, that there has been in certain quarters a reaction against extremes of theorizing in philosophy. But like so much philosophy, it can go too far. Further, if we are not careful about our explanations of how language works, we can and often do wind up with an environmental ethics that exalts human beings over the rest of nature, as I have tried to explain elsewhere.

Treat: Everything in moderation, right? Including moderation!

Post: Well, I hope this does not reduce to that or any other platitude!

Treat: I hope so too! I hope that nothing ever reduces to a platitude.

Post: It is a good thing I am a non-reductivist.