Natural Deduction·Rules·Lesson 3 of 5

Basic Natural Deduction

Introduces core natural deduction inference rules and trains students to build short, fully justified line-by-line proofs.

← Symbolizing Propositional Arguments Natural Deduction: Validity and Formal Proof Diagnosing Invalid Proof Steps →

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In this lesson · 7 sections · 5 worked examples · 2 practice activities

A proof is a justified sequence of lines
The core inference rules
How each rule works: side-by-side reference
Subproofs handle assumptions
…and 3 more

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