Ruth Barcan Marcus

Ruth Barcan Marcus ( born August 2, 1921 New York, † February 19, 2012, New Haven ) was an American philosopher and logician.

It is regarded as one of the founders of the quantified modal logic (or modal predicate logic) and the theory of rigid designation ( 'direct reference' ). According to her, the Barcan formula is named, that they themselves formulated first. In addition, as submitted by their relevant publications on the philosophy of logic, especially for essentialism, the need for the identity relation, and the status of possible, but not really existing objects ( possibilia ); further to the theory of epistemic beliefs, and conflicts of duty from the standpoint of deontic logic.

Life

Ruth Barcan grew up as the youngest of three sisters in a socialist- dominated household in the Bronx, New York on.

After high school, Ruth Barcan opted for the Washington Square College of New York University, where she attended mathematics, physics, classical literature, history and philosophy. Her influences there was one particular of the pragmatist Sidney Hook. Contrary to the weight that put this on the Philosophy of Science, Ruth Barcan primarily dealt with the history of ideas aspects of philosophy. Promotion learned Ruth Barcan by the mathematician and pioneer of game theory John Charles Chenoweth McKinsey, who directed her attention on the logical foundations of mathematics and modal logic.

After the acquisition of B. A. in mathematics and philosophy in 1941 joined Ruth Barcan to Yale University to continue to deal with modal logic. There she studied with Ernst Cassirer and Frederic Brenton Fitch. Here Ruth Barcan began to extensively deal with the philosophy of Bertrand Russell, in particular the logical system of Principia Mathematica and his theory of meaning. Looking back, she called Russell's work as the most important philosophical influence on her work.

After earning a Master's degree in 1942 Barcan PhD student was at Fitch, starting from the modal-logical calculi of Clarence Irving Lewis, she developed a modal predicate logic. Parts of their unpublished dissertation published previously in the Journal of Symbolic Logic, where they were discussed by Willard Van Orman Quine. In particular, their proof of the need for the identity relation in modal calculi broke it with the prevailing view. Her dissertation was adopted in 1946 at Yale.

Also in 1942, married Ruth Barcan the physicist Jules Alexander Marcus, whom she had met at Yale. A grant from the American Association of University Women allowed her to continue her studies with her husband at the University of Chicago, where she studied with Rudolf Carnap. 1948 her husband received a professorship at Northwestern University, she was able to accompany him only as ' visiting professor '. In 1952 she received a Guggenheim Fellowship. In the following years, Ruth Barcan Marcus brought four children to the world: James 1948, Peter 1949, Katherine 1952, Elizabeth 1957 Since 1959, she worked as a lecturer at Roosevelt University. .

In the early 60s, an intensive collaboration with David Kaplan developed, in 1962, she attended a seminar with Arthur Norman Prior to the University of Chicago.

A Discussion band and participating in a subsequent colloquium at Harvard University in Boston allowed it Barcan Marcus to defend their positions against Quine, whose negative reviews had until then slowed further development of modal predicate logic. The actual founding of the modal predicate logic performed by the Colloquium on Modal Theories and Many Valued Logic in August 1962 at the Barcan Marcus also took part. In 1963, Ruth Barcan Marcus Fellow of the National Science Foundation.

With the founding of the University of Illinois at Chicago Barcan Marcus in 1964 was appointed professor of philosophy and founding department chair. She was instrumental in establishing the Institute. Ruth Barcan Marcus 1970 moved to Northwestern, but she followed in 1973 a call to the Reuben Post Halleck - professorship at Yale University, which she held until her retirement in 1992. The marriage with Jules Marcus was divorced in 1976. During her time as an active faculty member at Yale she also took numerous visiting professorships: 1978-79 at the Stanford Center for Advanced Study in the Behavioral Sciences (1979 ), a Fellow at the Humanities Institute at the University of Edinburgh Fellow 1983, two terms in 1985 and 1968 at Wolfson College, Oxford University and as vistiting Fallow at Clare Hall, Cambridge Colledge University in 1988. After her retirement she remained as a Senior Research Scholar at Yale, she spent the winter but regularly as a guest professor at the University of California, Irvine.

Offices and honors

1961-1976 had Ruth Barcan Marcus held various offices and functions in area departments of the American Philosophical Association (APA ), whose chairman, she was also temporarily 1976-83 she served on the Board of Officers of the national umbrella organization. 1980-83, she was Vice President, 1983-86 President of the Association for Symbolic Logic.

Barcan Marcus was since 1986 the permanent members of the Common Room, Clare Hall, Cambridge. 1973 and 1990 she was a visiting fellow of the Rockefeller Foundation in Bellagio on Lake Como in 1973, she was co-opted into the Institut International de Philosophie, whose chairman 1989-92 she was, then we gave her an honorary chairman. In 1986, she gave a guest lecture at the Collège de France.

The Doctor of Humane Letters, honoris causa of the University of Illinois at Chicago was conferred in 1995, in 2000, the Wilbur Cross Medal from Yale University. In May 2008, the Foundation established a Lauener International Symposium on Analytical philosophy in her honor in Bern and awarded her the Lauener Price in analytical philosophy, named after Henri Lauener.

2007 Barcan Marcus Quinn received the Prize of the American Philosophical Association for her contribution to the professional association.

Philosophical positions

Modal predicate logic

Ruth Barcan Marcus earliest publications provide the first axiomatic formulation of a modal predicate logic. This early work represented an extension of the modal propositional logic systems of Clarence Irving Lewis and mark a milestone in the development of formal logic in the 20th century.

In the philosophy of logic, it represents an interpretation according to which the subject matter of an interpretation function includes the objects of the real world. She has also proposed an alternative to the usual model-theoretic semantics (Alfred Tarski ) for certain applications of logic, if " the truth conditions of quantified terms exclusively in the form of truth-conditions without recourse to an occupancy [ of logical terms ] can be specified. " Barcan Marcus is the succeeded in showing that such, even as truth value semantics ( truth value semantics ) or substitution semantics ( substitutional semantics ) does not lead to contradictions designated theory. While such a semantics is particularly relevant for a formalist theory of mathematics, sets by Barcan Marcus a correct understanding of ontological terms such as ( numerical ) identity needed an object- oriented semantics and a map function ahead. Barcan Marcus represents both a modal actualism, according to the merely possible objects ( so-called possibilia, possible, but not real objects ) does not logically meaningful entities are - a direct consequence of the fact that it restricts the assignment functions to individuals from the current world.

In formal systems, which suggests Barcan Marcus, therefore, the need for identity. Your interpretation of the identity based in the context of their theory of proper names and the Barcan formula that sparked a debate unfinished. See the Barcan formula also section quantifiers in modal logic products.

In addition, Barcan Marcus has argued against the view of Willard Van Orman Quine, that modal systems necessary imply a Aristotelian essentialism. She managed a definition essentialist properties in the context of formal systems from which they could show that they do not meet the requirements of an essentialist theory in certain interpretations of moral systems. This proof was formalized late Terence Parsons.

Theory of meaning

In the philosophy of language Barcan Marcus advocated a theory of rigid designation, according to which proper names only labels (tags), are directly related to their carrier (direct reference). The importance of proper names should be completely exhausted in this referential function, and not be dependent about a intension of the name. This Barcan Marcus contradicted the prevailing theories, labeling theory of Bertrand Russell and the bundle theory of John Searle. This position, which in 1962 introduced Barcan Marcus in the context of a Van Orman Quine held by colloquium, shows clear similarities to the theory of meaning of Saul Kripke, who introduced this a few years later in name and necessity. However, it is by no means ruled out that Kripke, who worked in the same problem area, regardless of Barcan Marcus came to his view.

Deontic logic

Barcan Marcus developed a modal theory to explain the conflict of duty. Ihrzufolge is to see a lot of morally prescriptive sentences as consistent if there is a possible world in which they can be all at the same time followed. This is tolerated, that there is a conflict between the commandments of this amount in the aktualen world - a conflict of duties. Thus, systems of moral rules would not necessarily inconsistent, just because there is a specific conflict of duty. This view has been met with great resistance.

Theory of epistemic beliefs

Barcan Marcus has the voice-centric approach to the explanation of beliefs, as it is found for Donald Davidson, back. According to the classical definition of knowledge, this is justified true belief ( justified true totaled ). According Barcan Marcus, it is wrong, a subject of knowledge attributed to a justified opinion, the content is something impossible (eg a contradictory statement ). An epistemic subject, that a conviction has owned, the content turns out to be wrong, can not say makes sense that it possessed this belief as a justified opinion, but that these have even falsely ascribed as a justified belief.

Anthologies and Editorial Boards

• The Logical Enterprise, ed with A. Anderson, R. Martin, Yale, 1995
• Logic, Methodology and Philosophy of Science, VII, eds. R. Barcan Marcus et al., North Holland, 1986
• Modalities: Philosophical Essays, Oxford University Press, 1993, paperback, . 1995 ( collection of their most important essay Publications )