Algebra of logic
Algebra of logic
is the name given to the Nineteenth Century form of the calculi of classes and propositions. It is distinguished from the contemporary forms of these calculi primarily by the absence of formalization as a logistic system (q.v.) The propositional calculus was also at first either absent or not clearly distinguished from the class calculus; the distinction between the two was made by Peirce and afterwards more sharply by Schrder (1891) but the identity of notation was retained.
Important names in the history of the subject are those of Boole (q.v.), De Morgan (q.v.), W. S. Jevons, Peirce (q.v.), Robert Grassmann, John Venn, Hugh MacColl, Schrder (q.v.), P. S. Poretsky — A.C.