 
Summary: Annals of Pure and Applied Logic 126 (2004) 34
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Editorial
Tarski once described himself as "being a mathematician (as well as a logician,
and perhaps a philosopher of a sort)". 1
This selfpresentation displays well the enor
mous scope of his scientiÿc activity. He produced fundamental works in mathematics,
logic, and philosophy, which summarized the old direction of research and opened new
perspectives. Set theory, topology, arithmetic, geometry, algebra, general and special
metamathematics, model theory, classical propositional calculus, LeÃsniewski's systems,
manyvalued logic, modal logic, intuitionistic logic, the calculus of relations, semantics,
the theory of truth. . . the list is not exhaustive. Although in the quoted selfpresentation
mathematics stands as the ÿrst, perhaps logic should be regarded as Tarski's basic ÿeld.
Logic in this context must be understood very broadly as covering formal logic, the
foundations of mathematics, and the philosophy of mathematics. However, these three
subÿelds of logic sensu largo should be again outlined widely in order to comprise
Tarski's works on various special and general problems. Most of his scientiÿc e orts
were devoted to a deeper understanding of fundamental concepts employed in mathe
matics and other sciences. This has always been a task of logicians and philosophers.
This volume contains a collection of papers presented at the Alfred Tarski Cente
