VENN, DIAGRAMMATIC...REPRESENTATION OF PROPOSITIONS AND REASONINGS, 1880; CATALOGUE OF A COLLECTION, 1889 (2 WORKS)

i. On the diagrammatic and mechanical representation of propositions and reasonings. [in:] The London, Edinburgh and Dublin Philosphical Magazine, and Journal of Science. Fifth Series. Vol. X, No. LIX, July 1880, pp.1-18. London: Taylor and Francis, 1880, 8vo, bound with other issues in volume X, later blue cloth, new endpapers, (bought from Chaucer Head, Presteigne, 2002), [T&W V9]ii. Catalogue of a collection of books on logic presented to the library. Cambridge: Cambridge University Press, 1889, 8vo, (book label of Alan Wright, Romsey, Hampshire; bought from Roger Gaskell, Warboys, 1993, Catalogue 6, item 92), [T&W V8]

Condition is described in the main body of the cataloguing, when appropriate
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THE PAPER IN WHICH VENN FIRST PROPOSES HIS INTERSECTING CIRCLES (subsequently known as the 'Venn diagram') AS A WAY OF EXTENDING THE LOGIC OF DIAGRAMS OF EULER TO COMPLEX LOGICAL PROBLEMS. This method of representing logical situations visually in geometrical form allow great versatility and functionality, and has become ubiquitous in many fields of modern life, whether illustrating set relationships in computer science, theoretical physics, medicine, creative writing and business strategy, or teaching elementary logical concepts to young students. The second item in the lot attests to the fact that Venn was also a collector and scholar on the history of logic. For Venn’s large research library described here, rich in antiquarian works, donated to his Cambridge College (Gonville and Caius), see Terry Boswell, "A note on John Venn as a collector and bibliographer of works on logic" in History and Philosophy of Logic 16 (1995), pp.121-125.