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Boolean algebra / propositional logic
theory
Boolean algebra / propositional logic — an engine domain that can touch it: formal_logic. Calibration: seals. Two values and three operations — AND, OR, NOT — with laws of their own (De Morgan's, distribution, double negation). Boole published it in 1847 as an attempt to put reasoning into algebra, with no application in view. IT SAT UNUSED FOR NINETY YEARS. Claude Shannon's 1937 master's thesis observed that a relay is either open or closed, so a switching circuit IS a Boolean expression — and every digital computer since has been built on that identification. It is the clearest case on this floor of pure structure waiting decades for the physical system that would need it, and an argument for keeping mathematics that has no use yet.
- on the shelf of → The theories the sciences and math run on — a theory the sciences and math run on, calibrated
- same form → Formal logic & epistemology (validity, inference) — Boole's algebra IS propositional inference in arithmetic dress: AND/OR/NOT over {0,1} repr
- connects at → Logic gates — the 16 functions of two inputs — Boolean algebra / propositional logic - the theory card of the same algebra
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