<biography, history of philosophy> British logician (1834-1923). In Symbolic Logic (1881) Venn applied the insights of Boole, Euler, and others in developing a diagrammatic method for testing the validity of categorical syllogisms. He also contributed to the development of modern theories of probability in The Logic of Chance (1867) and The Principles of Empirical or Inductive Logic (1889).
[A Dictionary of Philosophical Terms and Names]
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<logic, mathematics> John Venn's modern pictorial method of representing and evaluating the validity of categorical syllogisms. The classes designated by the terms of a syllogism are represented by overlapping circles, with shading and ×s indicating, respectively, the impossibility and existence of their common members. Recommended Reading: Sun-Joo Shin, The Logical Status of Diagrams (Cambridge, 1994).
[A Dictionary of Philosophical Terms and Names]
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