1901-1983

Polish-American mathematician-logician best known for developing the semantic method. Tarski's method made it possible to discuss the relationships between expressions and the extralinguistic objects they denote. This required making a distinction between the syntax of the language being studied and the metalanguage used to describe it. Tarski's researches also yielded a mathematical definition of truth in languages. He made other important contributions to mathematics, including the theory of inaccessible cardinals and the Banach-Tarski paradox.