Logical Positivism

There's a word for it
And words don't mean a thing
There's name for it
And names make all the difference in the world
Some things can never be spoken
Some things cannot be pronounced
That word does not exist in any language
It will never be uttered by a human mouth...
Let X make a statement
Let breath pass through those cracked lips

A.k.a. logical empiricism, neo-positivism. A philosophical movement --- if you will, an anti-philosophical movement --- inspired by Russell, Wittgenstein and a general disgust with metaphysics and Europe's going to hell after the Great War; British empricism in Continental dress.

The seed was a discussion group called the Vienna Circle, which introduced itself to the world with a 1929 manifesto modestly titled The Scientific World-View: The Vienna Circle. Immensely conscious of itself as a movement, it spread, by fission and by combination with similar, independent groups, into Poland (especially at Lwow), Czechslovakia, Germany, Britain (where A. J. Ayer was, so to speak, its apostle), Scandanvia, North America. The Vienna Circle remained particularly notorious, attracting such luminaries or luminaries-to-be as Tarski, von Neumann, Wiener (if memory serves) and Quine (who is, in some ways, the last survivor of the school). As Central and Eastern Europe collapsed in the '30s the Logical Postivists, liberals and social democrats to a man, were forced to flee westward, washing ashore in places ranging from the University of Chicago to a British public housing agency; or perish, like most of the Poles. The formal movement did not survive the Second World War, but as a general orientation, increasingly known as "logical empiricism", it lasted rather longer, say into the early sixties. It profoundly affected the whole of analytical philosophy, and mixed itself in with the foundations of modern physics, Einstein, Bohr and Born being sympathsizers and occasional attenders of conferences organized by the movement. (The "Copenhagen Interpretation" of quantum mechanics, for instance, which is the textbook version, and the one I adhere to on alternate days, is thoroughly in the spirit of the movement.) One is more embarrassed to mention the connection to behaviorism; apologists could easily show there's no incompatibility between logical empiricism and cognitive psychology, and indeed one of the founders of cognitive science was Herbert Simon, who was a student of Rudolf Carnap.

Logical Positivism's program centered around (to quote the title of one of Carnap's essays) "the elimination of metaphysics through the logical analysis of language." The idea was that, once people were no longer plagued by metaphysical nonsense (and they meant "nonsense" strictu sensu; see below), they would confine themselves to verifiable, scientific statements on the one hand, and poetry on the other, and cease to act like mad beasts. The instrument of this renovation was to be the "principle of verification", whose essence goes back to Hume:

When we run over libraries, persuaded of these principles, what havoc must we make? If we take in our hand any volume; of divinity or school metaphysics, for instance; let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames: for it can contain nothing but sophistry and illusion. [Enquiry Concerning Human Understanding, 12, "Of the Academical or Sceptical Philosophy", end]

Roughly, the principle of verification asserts that a statement is meaningful if and only if it is either purely formal ("abstract reasoning concerning quantity or number", modulo modern math and logic), or capable of empirical verification ("experimental reasoning concerning matter of fact and existence"); sometimes there was a rider identify the meaning of a statement with its method of verification. So (it was intended) "Rover is a large dog" is meaningful, along with "the cardinal number 3 is the class of all triples", "some apples are red", "no apples are red" (which happens to be false), even "all electrons are negatively charged". But "the Nothing nihilates" (a line of Heidegger's made notorious by Carnap's essay) is not meaningful, Plato's "the Good is the class of the determinate conceived as a unity" is not, "there is an omnipotent God" is not (since there is no way of verifying that an entity is infinitely powerful --- another point made by Hume), "the State is the image of the divine on Earth" (Hegel) is not; by the time one descends to ideological rubbish the holocaust is almost complete. (It was allowed that, while meaningless, many of these statements expressed emotions. The proper means of doing so, however, was poetry, and Carnap offered Nietzsche's Thus Spoke Zarathustra as an example of how to sublimate one's metaphysical urges. What Uncle Fritz himself would have made of this, I refuse to speculate.)

It was a very Enlightenment idea, as Neurath, for one, never tired of pointing out, and in the mind's ear one can hear Voltaire's mockery, beginning with O sancta simplicitas! For (writing off politicians, priests and metaphysicians as beyond redemption), supposing that ordinary people could be brought to accept verificationism and apply it in everyday life, they would have to know what, exactly, counts as "capable of empirical verification" . This looks easy enough to start, but getting the difference between "some apples are red" and "the Nothing nihilates" down in black and white proved terribly difficult. It lead to profound researches in mathematical logic, scientific methodology, semantics, semiotics. Successive formulations of the principle were increasingly subtle, increasingly hedged against the triple faults of being vague, of rejecting everything interesting, or (most distressing of all) passing absolutely anything. In the end the combined talents of all the Postivists and their associates (not exactly trifling) were quite defeated, and I don't think verificationism has a single living defender. (This "justly famous episode of black comedy in the history of philosophy", as David Stove calls it, played out, complete with plot twists and sight-gags, in the prefaces A. J. Ayer added to successive editions of Language, Truth and Logic.) --- Popper, who hung out with the Vienna Circle but insisted loudly, often and correctly that he was not a positivist of any description (just a first cousin) was moved by these difficulties to formulate his own "falsificationist" criterion for demarcating between science and metaphysics (which latter he did not say was meaningless). As might have been expected, it didn't fare much better.

Still... still... I, for one, can't help but feel that they were on to something, that something is fundamentally wrong with "the Nothing nihilates" and "God is omnipotent" that is not wrong with "all apples are puce" or even "Lyndon Johnson was President of Burkina Faso in 1965 and Lyndon Johnson was not President of Burkina Faso in 1965". But what, exactly, it is, I haven't the faintest, and I have ruminated about this elsewhere.

And artistic modernism (I can't think of any connection, other than that Ayer was a friend of e.e.cummings, but Serious Historians have claimed one exists). And the Great War. Russell. Popper. Wittgenstein. Ayer, Carnap, Nagel, Hempel. Quine. And pragmatism. And information theory and cybernetics. And cognitive science. Analytical philosophy generally. Contributions to mathematical logic. The curious resemblance to some parts of Nietzsche.

A. J. Ayer, Language, Truth and Logic
Rudolf Carnap, "The Elimination of Metaphysics through the Logical Analysis of Language" [Not on-line, but a very similar, and almost as good, essay on "The Rejection of Metaphysics", is]
Steven Gimbel, "If I Had A Hammer: Why Logical Positivism Better Accounts for the Need for Gender and Cultural Studies" [Online. Draws on the decidedly left-wing, social-democratic political views of the Logical Positivists, especially Reichenbach.]
Institute Vienna Circle
Leszek Kolakowski, A History of Positivist Philosophy from Hume to the Vienna Circle [=2nd ed. of Alienation of Reason]
Otto Neurath, Empiricism and Sociology and Philosophical Papers
Hans Reichenbach, The Direction of Time [Comments]
Schlik, Ethics
David Stove, The Plato Cult, and Other Philosophical Follies

Ayer (ed.), Logical Positivism
Rudolf Carnap
- The Continuum of Inductive Methods
- Introduction to the Philosophy of Science
- Introduction to Symbolic Logic and Its Applications
- The Logical Construction of the World
- The Logical Syntax of Language
- Meaning and Necessity: A Study in Semantics and Modal Logic
- Unity of Science
A. W. Carus, Carnap and Twentieth-Century Thought: Explication and Enlightenment [Blurb]
Anita Burdman Feferman, Alfred Tarski: Life and Logic
Michael Friedman
- A Parting of the Ways: Carnap, Cassirer and Heidegger
- Reconsidering Logical Positivism
Charles Morris
- Foundations of the Theory of Signs (in Neurath, Carnap and Morris (eds.), below)
- Signs, Language and Behavior
Otto Neurath, Rudolf Carnap and Charles Morris (eds.), International Encyclopedia of Unified Science [Only two volumes were ever published, the first in two parts.]
Hans Reichenbach
- Elements of Symbolic Logic [Much more than just a textbook on first-order logic...]
- Experience and Prediction
- The Rise of Scientific Philosophy
George Reisch, "From `The Life of the Present' to the `Icy Slopes of Logic': How the Cold War Killed Logical Empiricism" [On-line]
Alan W. Richardson, "Engineering Philosophy of Science: American Pragmatism and Logical Empiricism in the 1930s", Philosophy of Science 69 (2002): S36--S47
L. Susan Stebbing, Logical Positivism and Analysis
Michael Stöltzner, "The Principle of Least Action as the Logical Empiricist's Shibboleth," PITT-PHIL-SCI 616

Notebooks

Logical Positivism