6 articles
George Boole
George Boole (1815–1864) was an English mathematician who reduced logic to an algebra; his Boolean logic, applied to circuits by Claude Shannon, underlies modern digital computing.
Laws of Form
Laws of Form is a 1969 book by the British mathematician G. Spencer-Brown that introduces the calculus of indications, showing it equivalent to Boolean algebra and the propositional calculus.
Logical NOR
Logical NOR, also called joint denial, is the logical connective true only when both of its statements are false; on its own it can express every truth-function of propositional logic.
Propositional calculus
A propositional calculus is a formal proof system for propositional logic, given by axioms and inference rules such as modus ponens; first axiomatized by Frege in 1879, it is sound and complete.
Propositional logic
Propositional logic, also known as sentential logic or sentential calculus, studies reasoning with whole propositions that are true or false, joined by connectives like and, or, and if-then.
System L (logic)
System L is a name used in formal logic for several distinct deductive systems, chiefly Łukasiewicz's Hilbert-style axiomatization of classical propositional logic and the Curien–Herbelin term syntax for classical sequent calculus.