Quine's paper Two Dogmas of Empiricism, published 1951, is one of the most celebrated papers of twentieth century philosophy in the analytic tradition. The paper is an attack on two central parts of the logical positivists' philosophy. One is the distinction between analytic truths and synthetic truths, explained by Quine as truths grounded only in meanings and independent of facts, and truths grounded in facts. The other is reductionism, which is the theory that each meaningful statement gets its meaning from some logical construction of terms which refers exclusively to immediate experience. W. V. Quine Willard Van Orman Quine (June 25, 1908 - December 25, 2000) was one of the most influential American philosophers and logicians of the 20th century. ... 1951 (MCMLI) was a common year starting on Monday; see its calendar. ... (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s The 20th century lasted from 1901 to 2000 in the Gregorian calendar (often from (1900 to 1999 in common usage). ... Philosopher in Meditation (detail), by Rembrandt Philosophy is a field of study that includes diverse subfields such as aesthetics, epistemology, ethics, logic, and metaphysics, in which people ask questions such as whether God exists, whether knowledge is possible, and what makes actions right or wrong. ... Analytic philosophy is the dominant philosophical movement in University philosophy departments in English-speaking countries and in Scandinavia, although one of its founders, Gottlob Frege, was German, and many of its leading proponents, such as Ludwig Wittgenstein, Rudolf Carnap, Kurt Gödel, Karl Popper, Hans Reichenbach, Herbert Feigl, Otto Neurath... Logical positivism (later referred to as logical empiricism, rational empiricism, or neo-positivism) is a philosophy that combines positivism—which states that the only authentic knowledge is scientific knowledge—with a version of apriorism—the notion that some propositional knowledge can be had without, or “prior to”, experience. ... The terms analytic and synthetic are philosophical terms, used by philosophers to divide propositions into two types: analytic propositions and synthetic propositions. ... La Vérité by the French painter Jules Joseph Lefebvre Common dictionary definitions of truth mention some form of accord with fact or reality. ... A synthetic proposition is a proposition that is capable of being true or untrue based on facts about the world - in contrast to an analytic proposition which is true by definition. ... Reductionism in philosophy describes a number of related, contentious theories that hold, very roughly, that the nature of complex things can always be reduced to (be explained by) simpler or more fundamental things. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... Logic, from Classical Greek λόγος (logos), originally meaning the word, or what is spoken, (but coming to mean thought or reason) is most often said to be the study of criteria for the evaluation of arguments, although the exact definition of logic is a matter of controversy among philosophers. ...

"Two Dogmas" is divided into six sections. The first four sections are focused on analyticity, the last two sections on reductionism. In the last two sections, Quine turns the focus to the logical positivists' theory of meaning. He also presents his own holistic theory of meaning. Holism (from holos, a Greek word meaning all, entire, total) is the idea that all the properties of a given system (biological, chemical, social, mental, linguistic, etc. ...

Analyticity and circularity

Most of Quine's argument against analyticity in the first four sections is focused on showing that different explanations of analyticity are circular. The main purpose is to show that no satisfactory explanation of analyticity has been given.

Quine begins by making a distinction between two different classes of analytic statements. The first one is called logical true and has the form:

(1) No unmarried man is married

A sentence with that form is true independent of the interpretation of man and married, so long as the logical particles "no", "un-", "and" etcetera have their ordinary English meaning.

The statements in the second class have the form:

(2) No bachelor is married.

A statement with this form can be turned into a statement with form (1) by changing synonyms with synonyms, in this case bachelor with unmarried man. It is the second class of statements that lack characterization according to Quine. The notion of the second form of analyticity leans on the notion of synonymy, which Quine believes is in as much need of clarification as analyticity. Most of Quine's following arguments are focused on showing how explanations of synonymy end up being dependent on the notions of analyticity, necessity, or even synonymy itself. Synonyms (in ancient Greek syn συν = plus and onoma όνομα = name) are different words with similar or identical meanings. ...

How do we reduce sentences from the second class to a sentence of class (1)? Some might propose definitions. "No bachelor is married" can be turned into "No unmarried man is married" because "bachelor" is defined as "unmarried man". But, Quine asks: how do we find out that "bachelor" is defined as "unmarried man"? Clearly, a dictionary would not solve the problem, as a dictionary is a report of already known synonyms, and thus is dependent on the notion of synonymy, which Quine holds as unexplained.

A second suggestion Quine considers is an explanation of synonymy in terms of interchangeability. Two linguistic forms are (according to this view) synonymous if they are interchangeable without changing the truth-value. That is, in all contexts without change of truth value. But consider the following example:

(3)"Bachelor" has less than ten letters.

Obviously "bachelor" and "unmarried man" are not interchangeable in that sentence. To exclude that example and some other obvious counterexamples, such as poetic quality, Quine introduces the notion of cognitive synonymy. But does interchangeability hold as an explanation of cognitive synonymy? Suppose we have a language without modal adverbs like "necessarily". Such language would be extensional, in the way that two predicates which are true about the same objects are interchangeable again without altering the truth-value. Thus, there is no assurance that two terms that are interchangeable without the truth-value changing are interchangeable because of meaning, and not because of chance. For example, "creature with a heart" and "creature with kidneys" share extension.

In a language with the modal adverb "necessarily" the problem is solved, as salva veritate holds in the following case: This page is a candidate to be copied to Wiktionary using the Transwiki process. ...

(4) Necessarily all and only bachelors are unmarried men

while it does not hold for

(5) Necessarily all and only creatures with a heart are creatures with kidneys.

But to say (4) is according to Quine to say that the sentence "All and only all bachelors are unmarried men" is analytic. So for salva veritate to hold as a definition of synonymy, we need a notion of necessity and thus of analyticity.

Reductionism and Quine's holism

According to the logical positivists, a statement was given a meaning by its empirical verification. This view can be used to define synonymy. Two terms would be synonymous if and only if they are alike in method of empirical confirmation or infirmation. With the notion of synonymy, analyticity of the second class could be defined, and the problem would be solved. But Quine points out that this view needs an explanation of the methods which are to be compared. Reductionism is one of these methods, where a meaningful statement gets its meaning from some logical construct of terms which only refers to immediate experience. Reductionism depends on the assumption that each statement alone can admit of confirmation or infirmation. Quine however believes that all our statements "face the tribunal of sense experience not individually but only as a corporate body". Logical positivism (later referred to as logical empiricism, rational empiricism, or neo-positivism) is a philosophy that combines positivism—which states that the only authentic knowledge is scientific knowledge—with a version of apriorism—the notion that some propositional knowledge can be had without, or “prior to”, experience. ...

Quine holds these two theses as deeply connected with each other. When each statement is verified alone, it seems significant to talk about statements that are vacuously confirmed.

Instead of reductionism, Quine proposes that it is the whole field of science and not single statements that are verified. All scientific statements are interconnected in a force field. Logical laws give the relation between different statements, while they also are statements of the system. This makes talk about the empirical content of a single statement misleading. It also becomes impossible to draw a line between synthetic statements, which depend on experience, and analytic statements, that hold come what may. Any statement can be held as necessarily true according to Quine, if the right changes are done somewhere else in the system. In the same way, no statements are immune to revision. Hold come what may is a phrase popularized by the late Harvard philosophy professor, W. V. Quine. ...

Even logical laws can be revised according to Quine. Quantum logic, introduced by Garrett Birkhoff and John von Neumann, abandons the law of distributivity from classical logic in order to reconcile some of the apparent inconsistencies of classical boolean logic with the facts related to measurement and observation in quantum mechanics. Quine makes the case that the empirical study of physics has furnished apparently credible grounds for replacing classical logic by quantum logic, rather as Newtonian physics gave way to Einsteinian physics. The idea that logical laws are not immune to revision in the light of empirical evidence has provoked an intense debate, which we discuss in the article Is logic empirical?. In mathematical physics and quantum mechanics, quantum logic can be regarded as a kind of propositional logic suitable for understanding the apparent anomalies regarding quantum measurement, most notably those concerning composition of measurement operations of complementary variables. ... Garrett Birkhoff (January 19, 1911, Princeton, New Jersey, USA - November 22, 1996, Water Mill, New York, USA) was an American mathematician. ... John von Neumann (Neumann János) (December 28, 1903 – February 8, 1957) was a Hungarian mathematician and polymath of Jewish ancestry who made important contributions in quantum physics, functional analysis, set theory, economics, computer science, numerical analysis, hydrodynamics (of explosions), statistics and many other mathematical fields. ... Classical mechanics is a branch of physics which studies the deterministic motion of objects. ... For a non-technical introduction to the topic, please see Introduction to General relativity. ... Is logic empirical? is the title of two articles that discuss the radical concept, that the empirical facts about quantum phenomena may provide grounds for revising classical logic. ...

According to Quine, there are two different results of his reasoning. The first is a blurring of the line between metaphysics and natural science. Our theory about physical objects is epistemologically comparable to the gods of Homer. Quine believes in physical objects and considers it a scientific error not to, but not because of some epistemic difference in kind, but because the theory of physical objects has turned out to be a more efficient theory. To meet Wikipedias quality standards, this article or section may require cleanup. ... Epistemology is the branch of philosophy which studies the nature, origin, and scope of knowledge. ... The Homère Caetani bust at the Louvre, a 2nd century Roman copy of a 2nd century BC Greek original. ...

The second result is a move towards pragmatism. While pragmatic concerns are important for Carnap and other logical positivists when choosing linguistic framework, their pragmatism ends there. For Quine, every change in the system of science is, when rational, pragmatic. Pragmatism is a collection of many different ways of thinking. ... Rudolf Carnap (May 18, 1891 - September 14, 1970) was a German philosopher. ... In philosophy, the word rationality has been used to describe numerous religious and philosophical theories, especially those concerned with truth, reason, and knowledge. ...

Critique and influence

Grice and Strawson criticized "Two Dogmas" in their text In Defence of a Dogma. Among other things, they argue that Quine's skepticism about synonyms leads to a skepticism about meaning. If statements can have meanings, then it would make sense to ask "What does it mean?". If it makes sense to ask "What does it mean?", then synonymy can be defined as follows: Two sentences are synonymous if and only if the true answer of the question "What does it mean?" asked of one of them is the true answer to the same question, asked of the other. They also draw the conclusion that discussion about correct or incorrect translations would be impossible given Quine's argument. Four years after Grice and Strawson published their paper, Quine's book Word and Object was released. In the book he presented his theory of indeterminacy of translation, which makes the specific critique of Grices and Strawsons ineffective. Herbert Paul Grice (1913 - 1988), often writing under the name Paul Grice, was a philosopher remembered mainly for his substantial contribution to the study of meaning within language, particularly his maxims of conversation. ... Professor Sir Peter Frederick Strawson (November 23, 1919 – 13 February 2006) was an English philosopher. ... The neutrality of this article is disputed. ... The indeterminacy of translation is a thesis propounded by Willard Van Orman Quine, perhaps the most famous analytic philosopher of the 20th century. ...

In 'Two Dogmas' revisited, Putnam argues that Quine is attacking two different notions. Analytic truth defined as a true statement derivable from a tautology by putting synonyms for synonyms is near Kant's account of analytic truth as a truth whose negation is a contradiction. Analytic truth defined as a truth confirmed no matter what however, is closer to one of the traditional accounts of a priority. While the first four sections of Quine's paper concern analyticity, the last two concern a priority. Putnam considers the argument in the two last sections as independent of the first four, and at the same time as Putnam criticizes Quine, he also emphasizes his historical importance as the first top rank philosopher to both reject the notion of apriority and sketch a methodology without it. Hilary Whitehall Putnam (born July 31, 1926) is a key figure in the philosophy of mind during the 20th century. ... Tautology refers to a use of redundant language in speech or writing, or, put simply, saying the same thing twice. Within the study of logic, a tautology is a statement that is true by its own definition. ... Immanuel Kant (22 April 1724 – 12 February 1804), was a German philosopher from Königsberg (now Kaliningrad) in East Prussia. ... A priori is a Latin phrase meaning from the former or less literally before experience. In much of the modern Western tradition, the term a priori is considered to mean propositional knowledge that can be had without, or prior to, experience. ...

In his book Philosophical Analysis in the Twentieth Century, Volume 1 : The Dawn of Analysis Scott Soames (pp 360-361) has pointed out that Quine's circularity argument needs two of the logical positivists central theses to be effective: To meet Wikipedias quality standards, this article may require cleanup. ...

All necessary (and all a priori) truths are analytic

Analyticity is needed to explain and legitimate necessity.

It is only when these two theses are accepted that Quine's argument holds. It is not a problem that the notion of necessity is presupposed by the notion of analyticity if necessity can be explained without analyticity. According to Soames, both theses were accepted by most philosophers when Quine published Two Dogmas. Today however, Soames holds both statements to be antiquated.

External links

• Two Dogmas of Empiricism