David Lewis (philosopher)

DavidLewis

David Kellogg Lewis (September 28, 1941 – October 14, 2001) was an American philosopher renowned for his work in metaphysics, philosophy of language, philosophy of mind, and philosophical logic. He is best known for his theory of modal realism, which posits the existence of an infinite number of possible worlds that are just as real as the actual world we live in.

Early Life and Education[edit | edit source]

David Lewis was born in Oberlin, Ohio. He attended Swarthmore College, where he earned his B.A. in philosophy in 1962. He then went on to study at Harvard University, where he completed his Ph.D. in 1967 under the supervision of Willard Van Orman Quine.

Academic Career[edit | edit source]

Lewis began his teaching career at UCLA before moving to Princeton University in 1970, where he remained for the rest of his career. He was a prolific writer, publishing numerous influential papers and books.

Philosophical Contributions[edit | edit source]

Modal Realism[edit | edit source]

Lewis's most famous contribution to philosophy is his theory of modal realism. According to this theory, all possible worlds are as real as the actual world. This view contrasts with other theories of modality that treat possible worlds as mere abstractions or constructs.

Counterfactuals[edit | edit source]

In his book Counterfactuals (1973), Lewis developed a formal semantics for counterfactual conditionals. His approach uses the concept of possible worlds to analyze statements about what could have been the case if certain conditions had been different.

Causation[edit | edit source]

Lewis also made significant contributions to the analysis of causation. His counterfactual theory of causation, which he elaborated in several papers, argues that an event A causes an event B if and only if, had A not occurred, B would not have occurred.

Philosophy of Mind[edit | edit source]

In the philosophy of mind, Lewis is known for his defense of functionalism, the view that mental states are defined by their causal roles rather than by their intrinsic properties.

Convention[edit | edit source]

In his book Convention: A Philosophical Study (1969), Lewis analyzed the nature of social conventions and their role in coordinating human behavior. He argued that conventions are solutions to recurrent coordination problems.

Personal Life[edit | edit source]

Lewis was married to Stephanie Lewis, a fellow philosopher. He was known for his modesty, wit, and generosity as a mentor and colleague.

Legacy[edit | edit source]

David Lewis's work continues to influence contemporary philosophy. His theories and ideas are widely discussed and debated, and his contributions have left a lasting impact on various fields within philosophy.