Formal Logic; or, the Calculus of Inference, Necessary and Probable
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Augustus De Morgan's Formal Logic; or, the Calculus of Inference, Necessary and Probable (1847) was a significant work in the development of modern symbolic logic. De Morgan, a British mathematician and logician, is credited with formulating De Morgan's laws, which provide a way to transform logical statements into equivalent forms. These laws are crucial for simplifying complex logical expressions.123
De Morgan's work also emphasized the importance of relational inferences, suggesting they are central to mathematical and scientific reasoning. He introduced the concept of a "universe of discourse," a stipulated set of elements relevant to a logical discussion, which influenced later logical semantics. While his notation was considered clumsy, his contributions were vital to the reform and advancement of logic.24
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history of logicThe 16th century…Augustus De Morgan (De Morgan’s Formal Logic of 1847). The now standard discussions of validity, invalidity, and the self-conscious separation of “formal” from nonformal aspects of sentences and arguments all trace their roots to this work.
Read More…Augustus De Morgan (De Morgan’s Formal Logic of 1847). The now standard discussions of validity, invalidity, and the self-conscious separation of “formal” from nonformal aspects of sentences and arguments all trace their roots to this work.
Read More- history of logicBoole and De Morgan
…Augustus De Morgan published his Formal Logic; or, the Calculus of Inference, Necessary and Probable. Unlike Boole and most other logicians in the United Kingdom, De Morgan knew the medieval theory of logic and semantics and also knew the Continental, Leibnizian symbolic tradition of Lambert, Ploucquet, and Gergonne. The symbolic…
Read More…Augustus De Morgan published his Formal Logic; or, the Calculus of Inference, Necessary and Probable. Unlike Boole and most other logicians in the United Kingdom, De Morgan knew the medieval theory of logic and semantics and also knew the Continental, Leibnizian symbolic tradition of Lambert, Ploucquet, and Gergonne. The symbolic…
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