Analytic & pragmatist · 1920s – 1950s
Logical positivism (Vienna Circle)
A statement means something only if experience could verify it or logic alone makes it true; traditional metaphysics is therefore literally meaningless.
Which statements actually say something about the world?
In 1920s Vienna, scientists and philosophers gathered around Moritz Schlick, impressed by Einstein’s relativity and by the new logic of Frege, Russell and the Tractatus. They wanted a “scientific world-conception” and saw speculative metaphysics as an obstacle to clear thinking and social progress.
Logic and mathematics are true by the meanings of their symbols and say nothing about the world. Every other meaningful claim must, at least in principle, be checkable by observation. Sentences that are neither, such as “the Absolute is beyond time”, express attitudes or feelings, not facts.
- The meaning of a statement is its method of verification.
- Logic and mathematics are analytic, not factual.
- Philosophy’s task is to clarify the language of science.
The verification principle collapsed under criticism, not least because it fails its own test, but the movement set the agenda of philosophy of science; when Nazism forced its members into exile, they carried it to Britain and America.
Thinkers
1882–1936Moritz SchlickPhysicist-philosopher who led the Vienna Circle1891–1970Rudolf CarnapVienna Circle’s great system-builder, later in Chicago and Los Angeles1910–1989A. J. AyerOxford philosopher who brought logical positivism to English readersKey texts
Where it came from
Grew out ofEarly analytic philosophyThe Vienna Circle read Wittgenstein’s Tractatus line by line and took from Frege and Russell the idea that logic is empty of factual content.Grew out of
British empiricismHume’s division of all knowledge into “relations of ideas” and “matters of fact” became the positivists’ analytic–empirical divide.Reacted against
Kant’s critical philosophySeveral members started as Neo-Kantians, but all came to reject Kant’s synthetic a priori truths, partly because relativity overturned the Euclidean space Kant thought necessary.Reacted against
PhenomenologyCarnap’s 1932 essay on eliminating metaphysics used Heidegger’s “the Nothing itself nothings” as its prime example of a meaningless sentence.
What it led to
Opposed byCritical theory (Frankfurt School)Horkheimer and Adorno attacked positivism for treating existing facts as the limit of knowledge.Opposed by
Ordinary language philosophyOxford philosophers rejected the positivists’ ideal logical language and found philosophy’s material in the ordinary speech the positivists wanted to reform.Opposed by
Post-positivist philosophy of sciencePopper replaced verification with falsification, and Quine’s “Two Dogmas” rejected the analytic–synthetic distinction and the idea that sentences can be tested one by one.