Predicate Logic·Rules·Lesson 4 of 5

Quantifier Rules in Proof

Introduces the four quantifier inference rules (universal instantiation, existential instantiation, universal generalization, existential generalization) and explains the restrictions that each rule imposes.

← Multiple Quantifiers and Scope Predicate Logic: Quantifiers, Predicates, and Formal Structure Capstone: Quantified Reasoning in Mixed Arguments →

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In this lesson · 7 sections · 5 worked examples · 4 practice activities

From quantified formulas to usable instances
Existential instantiation requires a fresh name
Universal generalization requires arbitrariness
Existential generalization is the easy one
…and 3 more

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