Monday, April 27, 2015

Our granddaughter survived the earthquake in Nepal


Our granddaughter Lauren and her gap year group (“Himalaya B”)  were trekking on the Annapurna circuit when the quake hit. We had some anxious hours, but the whole group is fine and will be on its way to Besisahar in a few hours (7 to 10 hours by jeep).From there they will try to find transport to Pokhara where there is an airport.  Look at this blog:

Lauren asks us to tell friends to contribute to Oxfam, Doctors Without Borders, or Red Cross, etc. for Nepal relief (which is urgently needed in the aftermath of this terrible disaster). So that is what I am doing. Every contribution counts.

UPDATE Monday, April 28, 4:24PM
Lauren and her group have arrived in Pokhara, where they will stay until they can connect to a flight to the US from Kathmandu - probably not until May 2rd. They are in a guest house at the airport, and Pokhara suffered relatively light damage. Thanks for your sympathy, and again every contribution counts. 

Tuesday, April 21, 2015

Contextualism and “truth-evaluable content”
In 1976, when I delivered the John Locke Lectures at Oxford, I often spent time with Peter Strawson, and one day at lunch he made a remark I have never been able to forget. He said, "Surely half the pleasure of life is sardonic comment on the passing show".  This blog is devoted to comments, not all of them sardonic, on the passing philosophical show.
Hilary Putnam

In “Skepticism, Stroud, and the Contextuality of Knowledge”[1] I endorsed a view of meaning that I called “contextualism” (which I credited to Charles Travis, who in turn credits Austin and Wittgenstein, although the versions of each of these three philosophers—as well as, no doubt, mine—have significant differences, as I am sure Travis would agree). A key notion that I used in that essay is “truth-evaluable content”. Sanjit Chakraborty has asked me to say more about that notion, and I shall do that in forthcoming posts. (In the process of clarifying the notion, in the first instance for myself, I have discovered an interesting connection to a paper of Donald Davidson’s that many have found surprising, the famous “A Nice Derangement of Epitaphs”. But that is something to be discussed in the future posts.) Now I will begin this discussion by repeating the paragraphs of my essay in which I explained “contextualism” and “truth evaluable content”:

“In my previous writings on the subject of skepticism I have relied on what might be called a contextualist view of language in general and of the verb “to know” and its counterparts in other languages in particular. A contextualist view of language (the view that, as Charles Travis has so brilliantly explained, lies at the heart of the views of language of John Austin as well as of the later Wittgenstein[ii]), does not, of course, claim that the meanings of sentences vary from context to context, or at least it does not claim that in every sense of that multiply ambiguous word “meaning,” the meaning of a sentence that one understands changes whenever one finds oneself in a new context. In some sense it must be true that a speaker (as we say) “knows the meaning” of each sentence that he or she is able to use prior to using it or understanding another speaker’s use of it in a new context and that this “knowledge of its meaning” plays an essential role in enabling the speaker to know what the sentence is being used to say in the context.
(Let me also say here that I do not think of meanings as either platonic objects or as mental objects; in my view, talk of meanings is best thought of as a way of saying something about certain world-involving[iii] competences that speakers possess. And corresponding to those competences, there are constraints on what can be done with sentences without, as we say, “violating” or at least “extending” or “altering” their meaning.)
What contextualism does deny is that the “meaning” of a sentence in this sense determines the truth-evaluable content of that sentence. The thesis of contextualism is that in general the truth-evaluable content of sentences depends both on what they mean (what a competent speaker knows prior to encountering a particular context) and on the particular context, and not on meaning alone.
The easiest way to explain what I just said is with the aid of examples. Here is one that I used in a recent book[iv]: every competent speaker of English knows the meaning of the sentence “There is a lot of coffee on the table”. But, consistently with what it means, it is possible to understand that sentence as saying:
(1) There is a lot of (brewed) coffee on the table (e.g. in cups or mugs).
Sample context: “There is a lot of coffee on the table. Help yourself to a cup!”
(2) There are dozens of bags full of coffee beans on a table standing near a place where a truck has come to get them and take them to a warehouse.
Sample context: “There is a lot of coffee on the table. Load them in the truck.”
(3) A lot of coffee has been spilled on a table.
Sample context: “There is a lot of coffee on the table. Please wipe it up.”
Note that in one and the same context, the truth-value, the truth or falsity, of the sentence “There is a lot of coffee on the table” (or of the “content” that the speaker means to convey by uttering the sentence) will be quite different if the appropriate understanding of the sentence is as in the first example or as in the second example or as in the third example (and the number of possible non-deviant understandings of the sentence is much greater than three, in fact it is literally endless).
For example, if a speaker intends the first understanding and a hearer thinks the third understanding is meant, they will seriously misunderstand each other. Yet neither speaker nor hearer can be said not to know the meaning of the English sentence “There is a lot of coffee on the table”.[v] Nor can the speaker be accused of misusing the sentence, or the hearer of understanding it in a way that would be a violation (or extension, etc.) of its meaning. Thus there are at least three (in fact, as we just said, an endless number) of possible understandings of this sentence. And, if the view Travis ascribes to Austin and Wittgenstein is right, this is typical of sentences in any natural language. I call these understandings “truth-evaluable contents” (this is my terminology, not Travis’) because in the contexts we (very roughly) described they are typically sufficiently precise to be evaluated as true or false. (Note that even a vague sentence - “He stood roughly there” - can often be evaluated as true or false given an appropriate context. But it is also the case that these “contents” themselves admit of further specification, admit of different understandings in different contexts.[vi]

What I will do in the next posts (I expect it will take more than one) is try to fulfill Chakraborty’s request by saying in more precise terms,  ones that will be familiar to those acquainted with Tarskian semantics, how “truth-evaluable” content is to be understood.






[1] Collected as chapter 29 in my Philosophy in an Age of Science. The paragraphs I quote here are from the very beginning of that essay.






[ii] See Charles Travis’ book on Austin, The True and the False (Amsterdam: J. Benjamins, 1981) and his The Uses of Sense (Oxford: Clarendon Press, 1989), as well as his Unshadowed Thought (Cambridge, Mass.: Harvard University Press, 2000).
[iii] My reasons for saying world-involving competences are, of course, the by-now-familiar reasons for “semantic externalism” that I laid out in “The Meaning of ‘Meaning’” (in Minnesota Studies in the Philosophy of Science, vol. 7: Keith Gunderson, ed., Language, Mind and Knowledge ([Minneapolis: University of Minnesota Press, 1975], 131-193; reprinted in my Philosophical Papers, vol. 2: Mind, Language and Reality [Cambridge: Cambridge University Press, 1975], 215-271), and in chapter 2 of Representation and Reality (Cambridge, Mass.: MIT Press, 1988).
[iv] The Threefold Cord: Mind, Body and World (New York: Columbia University Press, 1999).
[v] I certainly know the meaning of the words, “there,” “coffee,” “a lot,” “is,” “on,” “the” and “table”. But that knowledge by itself does not determine the “truth value” of the sentence “There is a lot of coffee on the table”; in fact, the sentence, simply as a sentence, doesn’t have a truth-value apart from particular circumstances. Moreover, as I have explained, the truth-conditions of the sentence “There is a lot of coffee on the table” are highly occasion-sensitive: depending upon the circumstances, the sentence can be used to express different truth-evaluable contents. Responding to the coffee example, a philosopher of language of my acquaintance—one wedded to Grice’s distinction between the standard meaning of an utterance and its conversational implicatures—suggested that the “standard meaning” of “there is a lot of coffee on the table” is that there are many (how many?) molecules of coffee on the table. But if that is right, the “standard” sense is a sense in which the words are never used!
[vi] Stressed by Charles Travis in “Mind Dependence,” Revue Internationale de Philosophie, 55, 4 (2001): 503 (the issue is dedicated to my philosophy).

Thursday, April 9, 2015

Recommended readings on my philosophy of mathematics (continued):
In 1976, when I delivered the John Locke Lectures at Oxford, I often spent time with Peter Strawson, and one day at lunch he made a remark I have never been able to forget. He said, "Surely half the pleasure of life is sardonic comment on the passing show".  This blog is devoted to comments, not all of them sardonic, on the passing philosophical show.
Hilary Putnam

Yesterday’s post, which should be read before this one, began “Although I have posted a number of times about my philosophy of mathematics, it seems desirable to wrap up this series with some recommended readings (especially as I have the impression that some readers are trying to guess what that philosophy is and guessing wrong!). But first a few general remarks”. The general remarks were yesterday’s post. Today’s post is a list of just four readings by the two authors of what I yesterday called “the Hellman-Putnam modal-structural interpretation.”  Besides wanting to provide a short reading list for those who want to know what that interpretation really is, I confess that I also want to call attention to the fact that (after a long wait—I finished writing my Intellectual Autobiography and Replies in 2009!), my volume in The Library of Living Philosophers (titled, of course, The Philosophy of Hilary Putnam) will actually appear next month! Moreover, the first section of the volume is titled “Philosophy and Mathematics”. The fifth chapter of that section, Geoffrey Hellman’s “Infinite Possibilities and Possibilities of Infinity”, is not only an excellent explanation and short history of the modal-structural interpretation (which turns out to go back to Zermelo!—his paper, which Hellman cites, did not get translated into English until the late 1980s, and neither Hellman nor I knew of it), but also an account of open problems and work in progress. So here are the four readings:
By me: (1) “Mathematics without Foundations” (published in the Journal of Philosophy, Jan, 1967, and collected in my Mathematics, Matter of Method, Philosophical Papers  vol. I, Cambridge, 1975, and also collected in Benacerraf and Putnam, Philosophy of Mathematics; Selected Readings, second edition, Cambridge 1983.
By me: (2) “Set Theory: Realism, Replacement, and Modality” in my Philosophy in an Age of Science, Harvard, 2012.
By Hellman: (3) Mathematics without Numbers, Oxford, 1989
By Hellman: (4) “Infinite Possibilities and Possibilities of Infinity” in The Philosophy of Hilary Putnam, The Library of Living Philosophers, Open Court, 2015.
  




Wednesday, April 8, 2015

Recommended readings on my philosophy of mathematics and some general remarks about it
In 1976, when I delivered the John Locke Lectures at Oxford, I often spent time with Peter Strawson, and one day at lunch he made a remark I have never been able to forget. He said, "Surely half the pleasure of life is sardonic comment on the passing show".  This blog is devoted to comments, not all of them sardonic, on the passing philosophical show.
Hilary Putnam

Although I have posted a number of times about my philosophy of mathematics, it seems desirable to wrap up this series of posts on the subject with some recommended readings (especially as I have the impression that some readers are trying to guess what that philosophy is and guessing wrong!). But first a few general remarks.
General Remarks
(i) In “Mathematics without Foundations” I called what I just referred  to as “my philosophy of mathematics” “the modal-logical picture”. There I minimized its philosophical importance, referring to my “picture” as simply an alternative version (an “equivalent” description”) of the standard platonist ontology (“the mathematical object picture”).  Even then, however, I stressed that the very existence of this “equivalent description” showed that standard mathematics does not in and of itself require “ontological commitment” to what Quine famously called “intangible objects”.
(2) At least since “Mathematics without  Foundations”, I have insisted that what realism in philosophy of mathematics requires is that statements of pure mathematics have objective truth values whether or not human beings could or could not prove or disprove them. As Georg Kreisel once said, mathematics needs objectivity not objects.  My version of mathematical realism insists that statements to the effect that such-and-such is possible have objective truth values (so the position can be called “potentialism, or “possibleism”‑the latter sounds ugly, however, so I prefer the former), but rejects the idea that taking modality metaphysically seriously in this way requires positing the actual existence of “possible worlds”. It’s just modality all the way down.
(3) In earlier posts in this series I have explained why I now think the modal logical picture and the objectual picture are not “equivalent descriptions”, although the modal logical picture can be regarded as a rational reconstruction of a naïve “mathematical objects” picture.
(4) The technical core of the version I outlined in “Mathematics without Foundations” was a way of correlating each statement of classical set theory (set theory without individuals, in that paper) with a statement that employs  modal operators such as “it is possible that”, but whose predicates refer only to possible concrete objects—so the predicates are all nominalistically acceptable, and only nominalistically acceptable possible individuals are talked about. In a forthcoming paper*, Geoffrey Hellman calls these statements Putnam translates of the corresponding set theoretic statements.
Since the proper formalization of all this is something I owe to Hellman, I think the best way to refer to this philosophy of mathematics is “the Hellman-Putnam modal-structural interpretation”.
(to be continued)
*Geoffrey Hellman, "Infinite Possibilities and Possibilities of Infinity", details in next post.