John Venn (1834 â€1923) Essay

John Venn was born in 1834, to a highly religious Christian family at Hull, England. His mother died when he was very young and father was engaged with rendering his services to the church. He graduated from the Cambridge University and in 1857 was elected as a fellow of the college. He remained a fellow for the rest of his life. From 1858 he lived at different locations and finally returned to Cambridge in 1862. For the next thirty years, Venn dedicated himself to ‘Logic’. He wrote three books on this subject. The first one was ‘the logic of chance’ in 1866, the second, ‘ symbolic logic’ in 1881, and the third, ‘ The principles of Empirical logic’, in 1889. ( Brinley Lisa ) John Venn is famous for his conception of Venn diagrams, a visual representation of mathematical logic. He introduced the concept for the first time in 1880, in a paper titled, ‘ On the diagrammatic and mechanical representation of propositions and reasonings’, which appeared in the philosophical magazine and the journal of Science, July 1980. ( Brinley Lisa ). Venn Diagrams If three discs R, S ,T are subsets of U , then the intersections of these discs and their complements divide U into 8 regions, which do not overlap. The unions give 256 combinations of the three disks R, S , T. Proper working of Venn diagrams require an order of precedence and operators to follow. This order is, AND, NOT, OR, XOR ( Or and XOR equal ). This implies that if both the operations AND and OR are included in a query, AND operation will be taken up first. This does not happen ONLY IF parenthesis are used, as Expressions in parenthesis are processed first. Venn Diagram ( Brinley Lisa ) Venn continuously kept on improving his theory of visual representation through his diagrams. He never interpreted them as an attempt to clarify, what he thought were the inconsistencies and ambiguities of Boole’s logic. Venn realized that his diagrams were not sufficiently general. So he proposed a method by which a series of circles divide a plane into many compartments so that each successive circle would intersect all the compartments. This idea was to later develop as a concept of a ‘universal set ‘. At a later stage of his life, Venn became more interested in history and made some important contribution by documenting the history of Cambridge. John Venn will always be remembered for his contribution to extension of Boole’s logic, in a visual, diagrammatic way. Venn digrams are very useful in variety of applications including set theory, probability, logic, statistics and computer science. In a recent BBC poll, John Venn emerged as the third most greatest mathematician of recent times, next only to Newton and Euler. ( John Venn ) Works – cited page 1. Brinley Lisa, Gregory Emy, Biography of John Venn 1998, Retrieved on 22 March 07 from: < http://www. andrews. edu/~ calkins/math/biograph/biovenn. htm > 1. John Venn, wikipedia the free encyclopedia, 25 February 2007, Retrieved on 22 March 2007 from: < http://en. wikipedia. org/wiki/John_Venn>.