<history of philosophy, biography> british mathematician (1806-1871) who recognized the need to expand the notion of logical validity beyond the narrow confines of Aristotelian syllogistic. His works include Essay on Probabilities (1838), Formal Logic (1847), and Budget of Paradoxes (1872). De Morgan developed the standard statement of De Morgan's Theorems, a pair of logical relationships earlier noted by Ockham and Geulincx. Recommended Reading: Robert Adamson, Short History of Logic (Irvington, 1961) and Daniel Davy Merrill, Augustus De Morgan and the Logic of Relations (Kluwer, 1991).
[A Dictionary of Philosophical Terms and Names]
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