Sir Alfred Jules "Freddie" Ayer, usually cited as A. J. Ayer, was an English philosopher known for his promotion of logical positivism, particularly in his books Language, Truth, and Logic (1936) and The Problem of Knowledge (1956).
Logical positivism, later called logical empiricism, and both of which together are also known as neopositivism, was a movement in Western philosophy whose central thesis was the verification principle. Also called verificationism, this would-be theory of knowledge asserted that only statements verifiable through direct observation or logical proof are meaningful. Starting in the late 1920s, groups of philosophers, scientists, and mathematicians formed the Berlin Circle and the Vienna Circle, which, in these two cities, would propound the ideas of logical positivism.
Willard Van Orman Quine was an American philosopher and logician in the analytic tradition, recognized as "one of the most influential philosophers of the twentieth century." From 1930 until his death 70 years later, Quine was continually affiliated with Harvard University in one way or another, first as a student, then as a professor of philosophy and a teacher of logic and set theory, and finally as a professor emeritus who published or revised several books in retirement. He filled the Edgar Pierce Chair of Philosophy at Harvard from 1956 to 1978. A 2009 poll conducted among analytic philosophers named Quine as the fifth most important philosopher of the past two centuries. He won the first Schock Prize in Logic and Philosophy in 1993 for "his systematical and penetrating discussions of how learning of language and communication are based on socially available evidence and of the consequences of this for theories on knowledge and linguistic meaning." In 1996 he was awarded the Kyoto Prize in Arts and Philosophy for his "outstanding contributions to the progress of philosophy in the 20th century by proposing numerous theories based on keen insights in logic, epistemology, philosophy of science and philosophy of language."
Friedrich Ludwig Gottlob Frege was a German philosopher, logician, and mathematician. He worked as a mathematics professor at the University of Jena, and is understood by many to be the father of analytic philosophy, concentrating on the philosophy of language, logic, and mathematics. Though largely ignored during his lifetime, Giuseppe Peano (1858–1932) and Bertrand Russell (1872–1970) introduced his work to later generations of philosophers.
Rudolf Carnap was a German-language philosopher who was active in Europe before 1935 and in the United States thereafter. He was a major member of the Vienna Circle and an advocate of logical positivism. He is considered "one of the giants among twentieth-century philosophers."
The Logic of Scientific Discovery is a 1959 book about the philosophy of science by the philosopher Karl Popper. Popper rewrote his book in English from the 1934 German original, titled Logik der Forschung. Zur Erkenntnistheorie der modernen Naturwissenschaft, which literally translates as, "Logic of Research: On the Epistemology of Modern Natural Science"'.
Contemporary philosophy is the present period in the history of Western philosophy beginning at the early 20th century with the increasing professionalization of the discipline and the rise of analytic and continental philosophy.
Ernest Nagel was an American philosopher of science. Along with Rudolf Carnap, Hans Reichenbach, and Carl Hempel, he is sometimes seen as one of the major figures of the logical positivist movement.
The Lwów–Warsaw School was a Polish school of thought founded by Kazimierz Twardowski in 1895 in Lemberg, Austro-Hungary.
Timothy Williamson is a British philosopher whose main research interests are in philosophical logic, philosophy of language, epistemology and metaphysics. He is the Wykeham Professor of Logic at the University of Oxford, and fellow of New College, Oxford.
Verificationism, also known as the verification principle or the verifiability criterion of meaning, is the philosophical doctrine that only statements that are empirically verifiable are cognitively meaningful, or else they are truths of logic (tautologies).
Carlo Penco is an Italian analytic philosopher and full professor in philosophy of language at the University of Genoa in Italy.
Irving Marmer Copi was an American philosopher, logician, and university textbook author.
John Corcoran is an American logician, philosopher, mathematician, and historian of logic. He is best known for his philosophical work on concepts such as the nature of inference, relations between conditions, argument-deduction-proof distinctions, the relationship between logic and epistemology, and the place of proof theory and model theory in logic. Nine of Corcoran's papers have been translated into Spanish, Portuguese, Persian, and Arabic; his 1989 "signature" essay was translated into three languages. Fourteen of his papers have been reprinted; one was reprinted twice.
Nijaz Ibrulj is a Bosnian philosopher and a professor at the University of Sarajevo's Department of Philosophy and Sociology. He lectures on logic, analytic philosophy, methodology of social sciences, theory of knowledge, and cognitive science. His interests also extend to the field of social ontology. In 2000-2001 Ibrulj was awarded a Fulbright Visiting Scholarship to visit the University of California at Berkeley, where he worked with John Searle and Donald Davidson.
Matthew W. McKeon is the chair of the philosophy department at Michigan State University and well known philosopher of logic. McKeon earned his Ph.D. in philosophy at The University of Connecticut in 1994. He teaches courses in Logic and Philosophy of Language.
Eva Picardi was an Italian philosopher.
