Propositional and Predicate Logic
The formation rules of a propositional calculus may, for instance, take a form such that;
- if we take Φ to be a propositional formula we can also take ¬Φ to be a formula;
- if we take Φ and Ψ to be a propositional formulas we can also take (Φ & Ψ), (Φ → Ψ), (Φ Ψ) and (Φ Ψ) to also be formulas.
A predicate calculus will usually include all the same rules as a propositional calculus, with the addition of quantifiers such that if we take Φ to be a formula of propositional logic and α as a variable then we can take (α)Φ and (α)Φ each to be formulas of our predicate calculus.
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Read more about this topic: Formation Rule
Famous quotes containing the words predicate and/or logic:
“The predicate of truth-value of a proposition, therefore, is a mere fictive quality; its place is in an ideal world of science only, whereas actual science cannot make use of it. Actual science instead employs throughout the predicate of weight.”
—Hans Reichenbach (18911953)
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—Ellen Henrietta Swallow Richards (18421911)