Polish philosopher and logician. A pupil of Twardowski, Kotarbinski removed to Warsaw where he became professor and helped found the Centre of Logical Research. In the philosophy of language Kotarbinski was a firm nominalist and realist, mistrusting all abstraction, and firmly committed to a scientific philosophy. He had wide ethical and humanistic interests, and influence. Works included Elements of the Theory of Knowledge, Formal Logic, and Methodology of Science (1929) and Meditations on Worthy Life (1966).