University of Alberta
Department of Computing Science
CMPUT 272

Introduction to
Logic in Computing Science


H. James Hoover and Piotr Rudnicki



© 1994 H. James Hoover and Piotr Rudnicki


Table of Contents

0.1: Course Overview

Section 2: The Island of Knights and Knaves

Section 3: The Syntax and Fixed Semantics of MIZAR MSE

3.1: Identifiers, Sorts, Constants, Variables, and Terms

3.2: Predicates and Atomic Formulas

3.3: Logical Connectives and Compound Formulas

3.4: Conditionals and Biconditionals

3.5: Quantifiers

3.6: Scope and Binding

3.7: The Semantics of Quantified Formulas

3.8: BNF Grammar for Quantified Formulas

Section 4: Interpretations

4.1: Satisfiability and Falsifiability

4.2: Translations

4.3: Problems in translation

4.3.1: A question
4.3.2: Its answer

Section 5: Arguments

5.1: The Structure of MIZAR Arguments

5.2: Basic Inference Rules

5.2.1: Rewriting or Repetition, RE
5.2.2: Negation Elimination, NE
5.2.3: Negation Introduction, NI
5.2.4: Conjunction Elimination, CE
5.2.5: Conjunction Introduction, CI
5.2.6: Disjunction Elimination, DE
5.2.7: Disjunction Introduction, DI
5.2.8: Implication Elimination, IE, or Modus Ponens, MP
5.2.9: Implication Introduction, II
5.2.10: Equivalence Elimination, EqE
5.2.11: Equivalence Introduction, EqI
5.2.12: Equality Elimination, =E
5.2.13: Equality Introduction, =I
5.2.14: Rules for Quantifiers

5.3: Annotated Proofs

Section 6: Hypothetical Reasoning

6.1: Implication Introduction, II

6.2: Proof by Contradiction

6.2.1: Contradiction Introduction, ContrI
6.2.2: Negation Introduction, NI

6.3: Derived Rules Of Inference

6.3.1: Modus Ponens Twice
6.3.2: Double Negation Introduction
6.3.3: Reverse Implication Elimination or Modus Tollens (MT)
6.3.4: Excluded Middle
6.3.5: Chained Implication
6.3.6: Reverse Implication
6.3.7: Case Analysis
6.3.8: Equivalence Elimination
6.3.9: Equivalence Introduction
6.3.10: Divergence
6.3.11: De Morgan's Laws
6.3.12: More Disjunction Elimination
6.3.13: Another Implication Elimination
6.3.14: More Implication Introduction
6.3.15: Referencing Distributed Statements

6.4: The Notion Of Visibility in a Reasoning

6.5: Examples

Section 7: Inference Rules for Quantified Formulas and Equality

7.1: Bound Variable Renaming

7.2: Proper Free Substitution

7.3: Equality Elimination, =E

7.4: Universal Elimination, UE

7.5: Existential Introduction, ExI

7.6: Examples of Universal Elimination, and Existential Introduction

7.7: Universal Introduction, UI

7.8: Existential Elimination, ExE

7.9: De Morgan's Laws for Quantifiers

Section 8: Proofs

8.1: II, NI, PbyC, UI Rules Revisited

8.1.1: Proof of an Implication
8.1.2: Proof of a Negation
8.1.3: Proof by Contradiction
8.1.4: Universal Introduction

8.2: Proof Structures

8.2.1: Conjunction
8.2.2: Implication
8.2.3: Disjunction
8.2.4: Equivalence

8.3: Omitting Proofs

8.4: Incorporating proofs

8.5: thesis

8.6: MIZAR Problems on Knights and Knaves

8.6.1: Puzzle 1
8.6.2: Puzzle 2
8.6.3: A theorem about Knights and Knaves
8.6.4: Three more theorems
8.6.5: And even more theorems

Section 9: Interpretations Revisited

9.1: Premises

Appendix 1: Sample Mizar Proofs

1.1: A murder mystery

1.2: K. Schubert's Steamroller

Appendix 2: Mizar MSE Grammar

2.1: Notation

2.2: Grammar

2.3: Problems with syntax

2.3.1: A question
2.3.2: Its answer


March 20, 1998 -- Farren Layton -- farren@ugrad.cs.ualberta.ca