The Life and Works of Rudolf CarnapJune 27, 2021
Rudolf Carnap was born in West Germany in 1891.
He completed his secondary education at the Bartender’s Gymnasium and studied physics at the University of Jena between 1910 and 1914. During this period, he took a course where he read Kant’s masterpiece Critique der Reinen Vernunft. He also attended some of Gottlob Frege’s lectures. He served in the military for three years in the First World War and received permission from the army to study physics at the University of Berlin in 1917-1918. At that time, Albert Einstein had just been appointed to the same department as a professor. Carnap later transferred to the University of Jena and wrote a thesis in which he defended an axiomatic system of space and time. When the physics department found the thesis too philosophical and the philosophy department related to physics, he wrote a new thesis closer to Kantian views under the supervision of Bruno Bauch from the philosophy department. This thesis was published in an addendum of Kant Studien in 1922 with the title Der Raum (Space). In this work, Carnap sought to clarify the distinctions between formal, physical and perceptual or visual spaces.
Carnap corresponded with Russell in 1921 regarding the Principia Mathematica. He attended some seminars of Edmund Husserl in 1924 and 1925. He met Hans Reichenbach at a conference in 1923. Reichenbach brought Carnap into contact with Schlick, and Schlick offered Carnap an academic job at the University of Vienna. Carnap accepted this offer and started his academic studies at the University of Vienna in 1926. On the other hand, he made contact with the Vienna Circle and attended regular meetings.
Carnap wrote the Declaration of the Vienna Circle in 1929 with Otto Hahn and Otto Neurath. In the same year, he started publishing the Erkenntnis magazine with Hans Reicehenbach.
In 1928 Carnap published two books: Der logische Aufbau der Welt (The Logical Structure of the World) and Scheinproblem in der Philosophie (Pseudo Problems of Philosophy). In The Logical Structure of the World, Carnap sought to develop a formal system by which he would define scientific terms in terms of phenomenological terms. The formal system in question was based on a dual predicate, “similarity”. If two individuals were similar to each other, the said dual predicate was provided. The work also made maximum use of the logic developed in the Principia Mathematica. However, Carnap was not satisfied with the result himself and did not try to develop the project in the following years. (In fact, he did not even allow it to be translated into English until 1967.) In The Pseudo-Problems of Philosophy, he argued that many philosophical questions were actually meaningless because they resulted from the misuse of language. A direct consequence of the views Carnap defended in this book was the complete elimination of metaphysics from philosophical discourse.
In February 1930, the Polish logician and mathematician Alfred Tarski gave lectures in Vienna. The following November, Carnap visited Tarski in Warsaw and learned about his theoretical approach to semantics. (We discuss Tarski’s theory of truth in a separate subsection below.) Carnap was influenced by Tarski’s work and sought to incorporate Tarski’s approach to defining truth into his own philosophical project.
Carnap began his career as a professor at the University of Prague, whose language of instruction was German, in 1931. It was here that he penned his best-known work, Logische Syntax der Sprache (Logical Syntax of Language), and published it in 1934. In this work, he also introduced the “principle of tolerance”. According to this principle, there can be no language or logic that can be called “true”. Everyone is free to adopt a linguistic form that suits their purposes.
One of the historically interesting encounters is the meeting of Carnap and Quine in Prague. Quine, who was in Europe on a scholarship, met Carnap in Prague and had the opportunity to talk to him about Carnap’s work. Although their philosophical approaches differed radically from each other, the mutual respect established between these two philosophers in Prague continued throughout their lives.
With the rise of Nazism, Carnap felt threatened by his own socialist and pacifist views and immigrated to the United States in 1935. He has been a citizen of this country since 1941. He served as professor of philosophy at the University of Chicago from 1936-1952. He was at Harvard University between 1939-1941 at Quine’s invitation and mediation. He had the opportunity to come into contact with Alfred Tarski, who was there in the same years.
During his years in Chicago, Carnap wrote books on semantics, the logic of modalities, probability and the logic of induction. His work on the logic of modalities made reference to possible worlds and paralleled the work of Kripke that he had brought to the fore since 1959. He began his career at UCLA (University of California, Los Angeles) from 1954. Here, the focus of his work is philosophy of science, verification, etc. topics place