Editing Rudolf Carnap (section)

==Biography==
[[File:Wuppertal Ronsdorf - Villa Carnap 01 ies.jpg|thumb|Carnap's birthplace in Wuppertal]]
Carnap's father rose from being a poor ribbon-weaver to be the owner of a ribbon-making factory. His mother came from an academic family; her father was an educational reformer and her oldest brother was the [[archaeologist]] [[Wilhelm Dörpfeld]]. As a ten-year-old, Carnap accompanied Wilhelm Dörpfeld on an expedition to Greece.<ref name=DCDVlife>{{cite book|last=Quine, W.V. and Rudolf Carnap|title=Dear Carnap, Dear Van: The Quine-Carnap Correspondence and Related Work|url=https://archive.org/details/dearcarnapdearva00quin|url-access=limited|year=1990|publisher=University of California Press|location=Berkeley, CA|page=[https://archive.org/details/dearcarnapdearva00quin/page/n299 23]|isbn=9780520068476}}</ref> Carnap was raised in a profoundly religious [[Protestant]] family, but later became an atheist.<ref>[http://depts.washington.edu/vienna/carnap/carnapbio.htm Biography – UW Departments Web Server]</ref><ref>"Carnap had a modest but deeply religious family background, which might explain why, although he later became an atheist, he maintained a respectful and tolerant attitude in matters of faith throughout his life." Buldt, Bernd: "Carnap, Paul Rudolf", ''Complete Dictionary of Scientific Biography'', Vol. 20, p. 43. Detroit: Charles Scribner's Sons, 2008.</ref>

He began his formal education at the [[Barmen]] [[Gymnasium (school)|Gymnasium]] and the {{Interlanguage link|Carolo-Alexandrinum|de|3=Carolo-Alexandrinum (Jena)|lt=Carolo-Alexandrinum}} Gymnasium in [[Jena]].<ref>Mormann 2000, p. 14.</ref> From 1910 to 1914, he attended the [[University of Jena]], intending to write a thesis in [[physics]]. He also intently studied [[Immanuel Kant]]'s ''[[Critique of Pure Reason]]'' during a course taught by [[Bruno Bauch]], and was one of the very few students to attend [[Gottlob Frege]]'s courses in [[mathematical logic]].

During his university years, he became enthralled with the [[German Youth Movement]].<ref name=SEP>{{SEP|carnap|Rudolf Carnap|[[Hannes Leitgeb]], André Carus}}</ref>

While Carnap held moral and political opposition to [[World War I]], he felt obligated to serve in the German army. After three years of service, he was given permission to study physics at the [[University of Berlin]], 1917–18, where [[Albert Einstein]] was a newly appointed professor. Carnap then attended the [[University of Jena]], where he wrote a thesis defining an [[axiom|axiomatic theory]] of [[space]] and [[time]]. The physics department said it was too philosophical, and Bruno Bauch of the philosophy department said it was pure physics. Carnap then wrote another thesis in 1921, under Bauch's supervision,<ref name=Carus2019/> on the theory of space in a more orthodox [[Immanuel Kant|Kant]]ian style, published as ''Der Raum'' (''Space'') in a supplemental issue of ''[[Kant-Studien]]'' (1922).

Frege's course exposed him to [[Bertrand Russell]]'s work on logic and philosophy, which gave a sense of direction to his studies. He accepted the effort to surpass traditional philosophy with logical innovations that inform the sciences. He wrote a letter to Russell, who responded by copying by hand long passages from his ''[[Principia Mathematica]]'' for Carnap's benefit, as neither Carnap nor his university could afford a copy of this epochal work. In 1924 and 1925, he attended seminars led by [[Edmund Husserl]],<ref>Smith, D. W., and Thomasson, Amie L. (eds.), 2005, ''Phenomenology and Philosophy of Mind''. Oxford and New York: Oxford University Press, p. 8 n. 18.</ref> the founder of [[Phenomenology (philosophy)|phenomenology]], and continued to write on physics from a [[logical positivism|logical positivist]] perspective.

Carnap discovered a kindred spirit when he met [[Hans Reichenbach]] at a 1923 conference. Reichenbach introduced Carnap to [[Moritz Schlick]], a professor at the [[University of Vienna]] who offered Carnap a position in his department, which Carnap accepted in 1926. Carnap thereupon joined an informal group of Viennese intellectuals that came to be known as the [[Vienna Circle]], directed largely by Schlick and including [[Hans Hahn (mathematician)|Hans Hahn]], [[Friedrich Waismann]], [[Otto Neurath]], and [[Herbert Feigl]], with occasional visits by Hahn's student [[Kurt Gödel]]. When [[Ludwig Wittgenstein|Wittgenstein]] visited Vienna, Carnap would meet with him. He (with Hahn and Neurath) wrote the 1929 manifesto of the Circle, and (with [[Hans Reichenbach]]) initiated the philosophy journal ''[[Erkenntnis]]''.

In February 1930, [[Alfred Tarski]] lectured in Vienna, and during November 1930, Carnap visited Warsaw. On these occasions, he learned much about Tarski's [[model theory|model-theoretic]] method of [[semantics]]. [[Rose Rand]], another philosopher in the Vienna Circle, noted, "Carnap's conception of semantics starts from the basis given in Tarski's work, but a distinction is made between logical and non-logical constants, and between logical and factual truth... At the same time, he worked with the concepts of [[intension and extension]], and took these two concepts as a basis of a new method of semantics."<ref>{{cite web|last=Rand|first=Rose|title=Reading Notes and Summaries on Works by Rudolph Carnap, 1932 and Undated|url=http://digital.library.pitt.edu/u/ulsmanuscripts/pdf/31735061817825.pdf|work=Rose Rand Papers|publisher=Special Collections Department, University of Pittsburgh|access-date=May 16, 2013}}</ref>

In 1931, Carnap was appointed Professor at the German [[Charles University in Prague|University of Prague]]. In 1933, [[W. V. Quine]] met Carnap in Prague and discussed the latter's work at some length. Thus began the lifelong mutual respect these two men shared, one that survived Quine's eventual forceful disagreements with a number of Carnap's philosophical conclusions.

Carnap, whose [[socialism|socialist]] and [[pacifism|pacifist]] beliefs put him at risk in [[Nazi Germany]], emigrated to the United States in 1935 and became a [[naturalized citizen]] in 1941. Meanwhile, back in Vienna, Schlick was murdered in 1936. From 1936 to 1952, Carnap was a professor of philosophy at the [[University of Chicago]]. During the late 1930s, Carnap offered an assistant position in philosophy to [[Carl Gustav Hempel]], who accepted and became one of his most significant intellectual collaborators. Thanks partly to Quine's help, Carnap spent the years 1939–41 at [[Harvard University]], where he was reunited with Tarski.<ref>{{Cite book|title=Carnap, Tarski, and Quine at Harvard: Conversations on Logic, Mathematics, and Science|last=Frost-Arnold|first=Greg|publisher=Open Court|year=2013|isbn=9780812698374|location=Chicago|page=27}}</ref> Carnap (1963) later expressed some irritation about his time at Chicago, where he and [[Charles W. Morris]] were the only members of the department committed to the primacy of science and logic. (Their Chicago colleagues included [[Richard McKeon]], [[Charles Hartshorne]], and Manley Thompson.) Carnap's years at Chicago were nonetheless very productive ones. He wrote books on [[semantics]] (Carnap 1942, 1943, 1956), [[modal logic]], and on the philosophical foundations of [[probability]] and [[inductive logic]] (Carnap 1950, 1952).

After a stint at the [[Institute for Advanced Study]] in [[Princeton, New Jersey|Princeton]] (1952–1954), he joined the [[UCLA]] [[UCLA Department of Philosophy|Department of Philosophy]] in 1954, [[Hans Reichenbach]] having died the previous year. He had earlier refused an offer of a similar job at the [[University of California, Berkeley]], because accepting that position required that he sign a [[loyalty oath]], a practice to which he was opposed on principle. While at UCLA, he wrote on scientific knowledge, the [[analytic–synthetic distinction]], and the [[verification principle]]. His writings on [[thermodynamics]] and on the foundations of probability and [[inductive logic]] were published posthumously as Carnap (1971, 1977, 1980).

Carnap taught himself [[Esperanto]] when he was 14 years of age. He later attended the [[World Congress of Esperanto]] in Dresden in 1908.<ref>{{cite book |last1=Garcia |first1=Roberto |title=Esperanto and Its Rivals The Struggle for an International Language |date=2015 |publisher=University of Pensylvannia Press |page=87}}</ref> He also attended the 1924 Congress in Vienna, where he met his fellow Esperantist [[Otto Neurath]] for the first time.<ref>{{cite book |title=Ways of the Scientific World-Conception: Rudolf Carnap and Otto Neurath |date=2024 |publisher=Brill |page=2}}</ref>

In the USA, Carnap was somewhat politically involved. Carnap was a signatory of an open appeal distributed by the [[National Committee to Secure Justice in the Rosenberg Case]] to appeal for clemency in the case.<ref>{{cite book |title=Hearings Before the Committee on Un-American Activities, House of Representatives, Eighty-fourth Congress, Second Session Volume 5 |date=1956 |publisher=U.S. Government Printing Office}}</ref> He was listed as a 'sponsor' for the "National Conference to Appeal the [[Immigration and Nationality Act of 1952|Walter-McCarran Law]] and Defend Its Victims" organised by the [[American Committee for the Protection of the Foreign Born]],<ref>{{cite book |title=Hearing[s] Before the Committee on Un-American Activities, House of Representatives, Eighty-fourth Congress, First-second Sessions Volume 7 |date=1955 |publisher=U.S. Government Printing Office |page=8337}}</ref> and also for the "Scientific and Cultural Conference for World Peace" organised by the [[National Council of Arts, Sciences and Professions]].<ref>{{cite book |title=Hearings [and Reports] 82d Congress, 1st Session 1951 · Volume 2 |date=1951 |publisher=U.S. Government Printing Office |page=104}}</ref>

Carnap had four children by his first marriage to Elizabeth Schöndube, which ended in divorce in 1929. He married his second wife, Elizabeth Ina Stöger, in 1933.<ref name=DCDVlife /> Ina committed suicide in 1964.