Carl Gustav "Peter" Hempel (; ; January 8, 1905 – November 9, 1997) was a German

writer A writer is a person who uses written words in different writing styles, genres and techniques to communicate ideas, to inspire feelings and emotions, or to entertain. Writers may develop different forms of writing such as novels, short sto ...

philosopher Philosophy ('love of wisdom' in Ancient Greek) is a systematic study of general and fundamental questions concerning topics like existence, reason, knowledge, Value (ethics and social sciences), value, mind, and language. It is a rational an ...

, logician, and epistemologist. He was a major figure in logical empiricism, a 20th-century movement in the

philosophy of science Philosophy of science is the branch of philosophy concerned with the foundations, methods, and implications of science. Amongst its central questions are the difference between science and non-science, the reliability of scientific theories, ...

. Hempel articulated the deductive-nomological model of

scientific Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which stu ...

explanation An explanation is a set of statements usually constructed to describe a set of facts that clarifies the causes, context, and consequences of those facts. It may establish rules or laws, and clarifies the existing rules or laws in relation ...

, which was considered the "standard model" of scientific explanation during the 1950s and 1960s. He is also known for the

raven paradox The raven paradox, also known as Hempel's paradox, Hempel's ravens or, rarely, the paradox of indoor ornithology, is a paradox arising from the question of what constitutes evidence for the truth of a statement. Observing objects that are neith ...

("Hempel's paradox") and

Hempel's dilemma Hempel's dilemma is a question first asked (at least on record) by the philosopher Carl Hempel. It has relevance to naturalism and physicalism in philosophy, and to philosophy of mind. The dilemma questions how the language of physics can b ...

Education

Hempel studied

mathematics Mathematics is a field of study that discovers and organizes methods, Mathematical theory, theories and theorems that are developed and Mathematical proof, proved for the needs of empirical sciences and mathematics itself. There are many ar ...

physics Physics is the scientific study of matter, its Elementary particle, fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. "Physical science is that department of knowledge whi ...

and

philosophy Philosophy ('love of wisdom' in Ancient Greek) is a systematic study of general and fundamental questions concerning topics like existence, reason, knowledge, Value (ethics and social sciences), value, mind, and language. It is a rational an ...

at the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen (, commonly referred to as Georgia Augusta), is a Public university, public research university in the city of Göttingen, Lower Saxony, Germany. Founded in 1734 ...

and subsequently at the

University of Berlin The Humboldt University of Berlin (, abbreviated HU Berlin) is a public research university in the central borough of Mitte in Berlin, Germany. The university was established by Frederick William III on the initiative of Wilhelm von Humbol ...

and the Heidelberg University. In

Göttingen Göttingen (, ; ; ) is a college town, university city in Lower Saxony, central Germany, the Capital (political), capital of Göttingen (district), the eponymous district. The River Leine runs through it. According to the 2022 German census, t ...

, he encountered

David Hilbert David Hilbert (; ; 23 January 1862 – 14 February 1943) was a German mathematician and philosopher of mathematics and one of the most influential mathematicians of his time. Hilbert discovered and developed a broad range of fundamental idea ...

and was impressed by his program attempting to base all

on solid

logic Logic is the study of correct reasoning. It includes both formal and informal logic. Formal logic is the study of deductively valid inferences or logical truths. It examines how conclusions follow from premises based on the structure o ...

al foundations derived from a limited number of

axiom An axiom, postulate, or assumption is a statement that is taken to be true, to serve as a premise or starting point for further reasoning and arguments. The word comes from the Ancient Greek word (), meaning 'that which is thought worthy or ...

s. After moving to

Berlin Berlin ( ; ) is the Capital of Germany, capital and largest city of Germany, by both area and List of cities in Germany by population, population. With 3.7 million inhabitants, it has the List of cities in the European Union by population withi ...

, Hempel participated in a congress on scientific philosophy in 1929 where he met

Rudolf Carnap Rudolf Carnap (; ; 18 May 1891 – 14 September 1970) 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. ...

and became involved in the

Berlin Circle The Berlin Circle () was a group that maintained logical empiricist views about philosophy. History The "Berlin Circle" had its roots in seminars by Hans Reichenbach between 1926-1928, resulting in the formation of a group that included Reichenb ...

of philosophers associated with the Vienna Circle. In 1934, he received his doctoral degree from the

with a dissertation on

probability theory Probability theory or probability calculus is the branch of mathematics concerned with probability. Although there are several different probability interpretations, probability theory treats the concept in a rigorous mathematical manner by expre ...

, titled ''Beiträge zur logischen Analyse des Wahrscheinlichkeitsbegriffs'' (''Contributions to the Logical Analysis of the Concept of Probability'').

Hans Reichenbach Hans Reichenbach (; ; September 26, 1891 – April 9, 1953) was a leading philosopher of science, educator, and proponent of logical empiricism. He was influential in the areas of science, education, and of logical empiricism. He founded the ''G ...

was Hempel's main doctoral supervisor, but after Reichenbach lost his philosophy chair in Berlin in 1933,

Wolfgang Köhler Wolfgang Köhler (; 21 January 1887 – 11 June 1967) was a German psychologist and phenomenologist who, like Max Wertheimer and Kurt Koffka, contributed to the creation of Gestalt psychology. During the Nazi regime in Germany, he pro ...

and

Nicolai Hartmann Paul Nicolai Hartmann (; 20 February 1882 – 9 October 1950) was a German philosopher. He is regarded as a key representative of critical realism and as one of the most important twentieth-century metaphysicians. Biography Hartmann was born a ...

became the official supervisors.

Career

Within a year of completing his doctorate, the increasingly repressive and anti-semitic Nazi regime in Germany had prompted Hempel to emigrate to Belgium as his wife was of

Jewish Jews (, , ), or the Jewish people, are an ethnoreligious group and nation, originating from the Israelites of History of ancient Israel and Judah, ancient Israel and Judah. They also traditionally adhere to Judaism. Jewish ethnicity, rel ...

ancestry. In this he was aided by the scientist Paul Oppenheim, with whom he co-authored the book ''Der Typusbegriff im Lichte der neuen Logik'' on typology and logic in 1936. In 1937, Hempel emigrated to the United States, where he accepted a position as Carnap's assistant at the

University of Chicago The University of Chicago (UChicago, Chicago, or UChi) is a Private university, private research university in Chicago, Illinois, United States. Its main campus is in the Hyde Park, Chicago, Hyde Park neighborhood on Chicago's South Side, Chic ...

. He later held positions at the

City College of New York The City College of the City University of New York (also known as the City College of New York, or simply City College or CCNY) is a Public university, public research university within the City University of New York (CUNY) system in New York ...

(1939–1948),

Yale University Yale University is a Private university, private Ivy League research university in New Haven, Connecticut, United States. Founded in 1701, Yale is the List of Colonial Colleges, third-oldest institution of higher education in the United Stat ...

(1948–1955) and

Princeton University Princeton University is a private university, private Ivy League research university in Princeton, New Jersey, United States. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial ...

, where he taught alongside

Thomas Kuhn Thomas Samuel Kuhn (; July 18, 1922 – June 17, 1996) was an American History and philosophy of science, historian and philosopher of science whose 1962 book ''The Structure of Scientific Revolutions'' was influential in both academic and ...

and remained until made

emeritus ''Emeritus/Emerita'' () is an honorary title granted to someone who retires from a position of distinction, most commonly an academic faculty position, but is allowed to continue using the previous title, as in "professor emeritus". In some c ...

in 1973. Between 1974 and 1976, he was an emeritus at the Hebrew University in Jerusalem before becoming University Professor of Philosophy at the

University of Pittsburgh The University of Pittsburgh (Pitt) is a Commonwealth System of Higher Education, state-related research university in Pittsburgh, Pennsylvania, United States. The university is composed of seventeen undergraduate and graduate schools and colle ...

in 1977 and teaching there until 1985. In 1989 the Department of Philosophy at Princeton University renamed its Three Lecture Series the 'Carl G. Hempel Lectures' in his honor. He was an elected member of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...

and of the

American Philosophical Society The American Philosophical Society (APS) is an American scholarly organization and learned society founded in 1743 in Philadelphia that promotes knowledge in the humanities and natural sciences through research, professional meetings, publicat ...

for which he served as president. Hempel died, aged 92, on November 9, 1997 at a nursing home near Princeton, New Jersey.

Philosophical views

Hempel never embraced the term "

logical positivism Logical positivism, also known as logical empiricism or neo-positivism, was a philosophical movement, in the empiricist tradition, that sought to formulate a scientific philosophy in which philosophical discourse would be, in the perception of ...

" as an accurate description of the Vienna Circle and Berlin Group, preferring to describe those philosophers, including himself, as "logical empiricists." He believed that the term "

positivism Positivism is a philosophical school that holds that all genuine knowledge is either true by definition or positivemeaning '' a posteriori'' facts derived by reason and logic from sensory experience.John J. Macionis, Linda M. Gerber, ''Soci ...

," with its roots in the

materialism Materialism is a form of monism, philosophical monism according to which matter is the fundamental Substance theory, substance in nature, and all things, including mind, mental states and consciousness, are results of material interactions. Acco ...

Auguste Comte Isidore Auguste Marie François Xavier Comte (; ; 19 January 1798 – 5 September 1857) was a French philosopher, mathematician and writer who formulated the doctrine of positivism. He is often regarded as the first philosopher of science in the ...

, implied a

metaphysics Metaphysics is the branch of philosophy that examines the basic structure of reality. It is traditionally seen as the study of mind-independent features of the world, but some theorists view it as an inquiry into the conceptual framework of ...

that empiricists were not obliged to embrace. He regarded

Ludwig Wittgenstein Ludwig Josef Johann Wittgenstein ( ; ; 26 April 1889 – 29 April 1951) was an Austrian philosopher who worked primarily in logic, the philosophy of mathematics, the philosophy of mind, and the philosophy of language. From 1929 to 1947, Witt ...

as a philosopher with a genius for stating philosophical insights in striking and memorable language, but believed that he, or at least the Wittgenstein of the '' Tractatus,'' made claims that could only be supported by recourse to

. To Hempel, metaphysics involved claims to know things which were not knowable; that is, metaphysical hypotheses were incapable of confirmation or disconfirmation by evidence. In his exploration of the

, Hempel brought to light the significant contributions of 19th-century Hungarian

physician A physician, medical practitioner (British English), medical doctor, or simply doctor is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through the Medical education, study, Med ...

Ignaz Semmelweis Ignaz Philipp Semmelweis (; ; 1 July 1818 – 13 August 1865) was a Hungarian physician and scientist of German descent who was an early pioneer of antiseptic procedures and was described as the "saviour of mothers". Postpartum infections, ...

. His examination of Semmelweis's systematic discovery in addressing a scientific problem provided a historical context for Hempel's own reflections. This account of Semmelweis's work notably influenced Hempel's thoughts on the role of ' induction' in scientific inquiry. He considered Semmelweis's approach as a pivotal example of how

empirical evidence Empirical evidence is evidence obtained through sense experience or experimental procedure. It is of central importance to the sciences and plays a role in various other fields, like epistemology and law. There is no general agreement on how the ...

and inductive reasoning play a crucial role in the development of scientific knowledge, further enriching his perspective on logical empiricism. Hempel is also credited with the revival of the Deductive-nomological model of explanation in the 1940s with the publication of "The function of general laws in history".

Legacy

In 2005, the City of Oranienburg, Hempel's birthplace, renamed one of its streets "Carl-Gustav-Hempel-Straße" in his memory.

Bibliography

Principal works

*1936: "Über den Gehalt von Wahrscheinlichkeitsaussagen" and, with Paul Oppenheim, "Der Typusbegriff im Licht der neuen Logik" *1942: "The Function of General Laws in History" *1943: "Studies in the Logic of Confirmation" *1959: "The Logic of Functional Analysis" *1965: '' Aspects of Scientific Explanation'' *1966: '' Philosophy of Natural Science''

Essay collections

*'' Aspects of Scientific Explanation and Other Essays'' (1965), . *''Selected Philosophical Essays'' (2000), . *''The Philosophy of Carl G. Hempel: Studies in Science, Explanation, and Rationality'' (2001), .

Articles

″On the Nature of Mathematical Truth"
and "Geometry and Empirical Science" (1945), ''American Mathematical Monthly'', issue 52. *Articles in '' Readings in Philosophical Analysis'' (pp. 222–249), edited by Herbert Feigl and Wilfrid Sellars (Appleton-Century-Crofts, Inc., 1949).

References

External links

"Problems and Changes in the Empiricist Criterion of Meaning" by Carl G. Hempel

Carl Gustav Hempel Papers, 1903-1997, ASP.1999.01
at the Archives of Scientific Philosophy, Special Collections Department, University of Pittsburgh. {{DEFAULTSORT:Hempel, Carl Gustav 1905 births 1997 deaths 20th-century German essayists 20th-century German male writers 20th-century German philosophers City College of New York faculty Empiricists German logicians German male essayists German male non-fiction writers Academic staff of the Hebrew University of Jerusalem Heidelberg University alumni Humboldt University of Berlin alumni Logical positivism People from Oranienburg People from the Province of Brandenburg Philosophers of logic Philosophers of mathematics German philosophers of science German philosophy academics Princeton University faculty University of Göttingen alumni University of Pittsburgh faculty Vienna Circle Yale University faculty Corresponding fellows of the British Academy Presidents of the American Philosophical Society