Meaning And Necessity A Study In Semantics And Modal logic

by Rudolf Carnap

The main purpose of this book is the development of a new method for the semantical analysis of meaning, that is, a new method for analyzing and describing the meanings of linguistic expressions. This method, called the method of extension and intension, is developed by modifying and ex tending certain customary concepts, especially those of class and property. The method will be contrasted with various other semantical methods used in traditional philosophy or by contemporary authors. These other methods have one characteristic, all regard an expression in a language as a name of a concrete or abstract entity. In contradistinc tion, the method here proposed takes an expression, not as naming any thing, but as possessing an intension and an extension. This book may be regarded as a third volume of the series which I have called Studies in Semantics, two volumes of which were published earlier. However, the present book does not presuppose the knowledge of its predecessors but is independent. The semantical terms used in the present volume are fully explained in the text. The present method for defining the L-terms for example, L-true, meaning logically true, analytic differs from the methods discussed in the earlier Introduction to Semantics. I now think that the method used in this volume is more satisfactory for lan guages of a relatively simple structure. After meaning analysis, the second main topic discussed in this book is modal logic, that is, the theory of modalities, such as necessity, contin gency, possibility, impossibility, etc. Various systems of modal logic have been proposed by various authors. It seems to me, however, that it is not possible to construct a satisfactory system before the meanings of the modalities are sufficiently clarified. I further believe that this clarification can best be achieved by correlating each of the modal concepts with a cor responding semantical concept for example, necessity with L-truth. It will be seen that this method also leads to a clarification and elimination of certain puzzles which logicians have encountered in connection with modalities. In the Preface to the second volume of Studies in Semantics, I announced my intention to publish, as the next volume, a book on modal logic containing, among other things, syntactical and semantical systems which combine modalities with quantification. The present book, however, is not as yet the complete fulfilment of that promise it contains only analyses and discussions of modalities, preliminary to the construction of modal systems The systems themselves are not given here. In an article published elsewhere see Bibliography, I have stated a calculus and a semantical system combining modalities with quantification, and have summarized some of the results concerning these systems. A more comprehensive exhibition of results already found and those yet to be found must be left for another time. The investigations of modal logic which led to the methods developed in this book were made in 1942, and the first version of this book was writ ten in 1943, during a leave of absence granted by the University of Chicago and financed by the Rockefeller Foundation. To each of these institutions I wish to express my gratitude for their help. Professors Alonzo Church and W. V. Quine read the first version and discussed it with me in an extensive correspondence...

Genres: Philosophy, Logic, Nonfiction, Linguistics, Language

253 pages, Kindle Edition

First published January 1, 1947

About the author

Rudolf Carnap, a German-born philosopher and naturalized U.S. citizen, was a leading exponent of logical positivism and was one of the major philosophers of the twentieth century. He made significant contributions to philosophy of science, philosophy of language, the theory of probability, inductive logic and modal logic. He rejected metaphysics as meaningless because metaphysical statements cannot be proved or disproved by experience. He asserted that many philosophical problems are indeed pseudo-problems, the outcome of a misuse of language.

Read more : http://www.iep.utm.edu/carnap/

Reviews

[path · Rating 4 out of 5]

“for every expression which we can understand, there is the question of meaning and the question of actual application; therefore, the expression has primarily an intension and secondarily an extension” (203).

I can appreciate what it appears that Carnap is trying to do here: making the language through which we make propositions about the world ultimately accountable to real things in the world that uphold their truth value. And he is attempting to do this while acknowledging that there are various ways that we use language within a given semantic systems that prevail in a place, among members of a community, at a given moment in time. Ultimately, the project seems both far too complex and too limited in scope. And try as he might, Carnap is far from a pleasurable read.

Two terms that are essential to Carnap’s discussion are extension and intension. As I take it, intension refers to instances and particularities of a concept or sign; it is the sense in which a word means something to us at this moment and in this place where we are specifically acquainted with it. Extension refers to the more generalized class to which all of those senses of a word belong. So, for example, we might have different intensional uses of a word like a tree: we could refer to this beech tree, this source of firewood, this source of shade, this object of natural beauty all of which are meaningful ways of referring to the tree before us. The extension of those meaningful phrases, where they all converge, is in the tree itself, which is empirically verifiable. Intensional ways of talking about a tree are needed for making propositions about the thing … it is or isn’t a source of firewood; it is or isn’t a beech tree; it is or isn’t providing shade, etc. The thing that the tree is in the world, its extension is what makes those propositions true or false, and it is what determines what can be sensible propositions about the thing at all. A proposition like “this tree is a thing of beauty” is not reconcilable to the tree itself and cannot be verified true or false — it is a nonsense proposition.

Carnap invents a whole system of semantic categories for distinguishing between things that are true in the world and things that are true in our localized use. This is the difference between true/equivalent/determinant (extensional) and L-true/L-equivalent/L-determinant (intensional). All statements have both intensional and extensional aspects. And it gets to be a little much in a way. But perhaps responding to some of the push back about how fussy logical approaches to language and truth become, Carnap says that we really don't need to talk about things as having extensional and intensional meaning and he instead suggests a "metametalanguage" (yes, that's the term he uses) that is the same thing as common sense usage (i.e., intuitive language use) model, saying that instead of talking about a "tree" in its intensional instantiations and a "Tree" in its extensional way, we can just say "tree" and rely on the meaning of the word as it is used. The chapters on logic are just the proof that everything cashes out the way he says it does.

I am interested in this idea for its utility in thinking about semantics and the way that words and concepts come to be used in local ways and acquire shared meaning. Meaning is iterated in local use and we can develop new meanings for words and concepts that respond to the variations of our situations. Words have a kind of plasticity to them that allow for small variations in the localized use of a term to be subsumable to a more generalized understanding of the term that can then be used to impose coherence across situations where it is used. And as long as the logic of the local semantic system is followed well enough that people recognize that the proliferation of intensional meanings is resulting in valid, sensible uses then local meaning holds. The challenge, however is in making sure that localized meaning does not become isolated from other meanings or extensions of those ideas. Already we can see how this kind of insular sense making is happening in media bubbles and other information filters that disrupt the way that intensional meanings ought to relate to extensional contexts. It becomes easy to justify the meaning of words or signs or symbols by making them fit others in a particular intensional context of understanding if those meanings are not subjected to the standard of assessing truth value in the extensional context into which intensional meaning ought to collapse. Whether empirical verification is the only standard of truth is another question because of its limited applicability and inability to touch matters like ethics and morality.

So, the agenda here is in making the proliferation of intensions responsible to the scientism of empirical verification. And I am sympathetic to this goal, but Carnap’s approach does limit us to just talking about propositions and not about ranges of human experience or psychological states or feelings or emotions which fall outside the realm of meaning as it is constructed here because how can our collective feelings about something ultimately fall under the same extensional class? He is clear to say that intensional and extensional, as he theorizes them are not intended to be applicable to other forms of discourse.

[Jonathan Hockey · Rating 3 out of 5]

An interesting attempt to logically construct semantics with an intensional and extensional approach, contrasted with the name-relation approach, of which he points out various difficulties and problems.

[Andrew Noselli · Rating 3 out of 5]

I read the first chapter of 66 pages yesterday and my head was pounding so hard at the end that I had to sleep for twelve hours. I skimmed the rest today while listening to Renee Fleming and Cats Down Under the Stars. I tried to read the notes as best I could but, in the end, I raced back to authors I could understand, like Isaiah Berlin and Noam Chomsky. I'd like to know if my friend Ivan Welty can understand this book, but somehow I doubt it... It's a very difficult text, what starts out as straightforward definitions become written over and out-rivaled by further definitions that requires an implicitly metalinguistic-mathematical training and it seems to me that only a very select audience can hope to accompany Carnap on his extra-logical voyages of intellectual daring.

[Elia Mantovani · Rating 1 out of 5]

Read because of a metaphysics module. This book is very tough to get through. One the one hand, the distinction between intension and exstension incredibly recalls the Fregean one between Sinn and Bedeutung. On the other, the section on model logic is very difficult to understnad and, from time to time, seems completely loosing its original focus. However, together with Quine, Carnap marks an important point within the timeline of analytic philosophy, i.e. the new approach intermingling semantics with ontology and metaphysics.

[Shannon · Rating 5 out of 5]

as dense as this stuff is, carnap is able to lead you through it and make you really feel like you're getting it. good read and some good responses to willard quine, arch nemesis of all things modal.