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Computer Science
Computer Science Fundamentals
Logic for Computer Science
1. Introduction to Logic in Computer Science
2. Propositional Logic
3. Proof Systems for Propositional Logic
4. First-Order Logic
5. Logic and Computation
6. Applications in Hardware Design
7. Applications in Software Engineering and Verification
8. Applications in Artificial Intelligence
9. Applications in Database Systems
10. Advanced Topics in Logic
First-Order Logic
Motivation and Limitations of Propositional Logic
Expressiveness Limitations
Need for Quantification
Need for Relations and Functions
Examples Requiring First-Order Logic
Syntax of First-Order Logic
Vocabulary
Constants
Individual Constants
Naming Objects
Variables
Individual Variables
Role in Quantification
Function Symbols
Function Symbols and Arity
Function Terms
Predicate Symbols
Predicate Symbols and Arity
Relations
Terms
Simple Terms
Complex Terms
Ground Terms vs Non-Ground Terms
Atomic Formulas
Predicate Applications
Equality
Complex Formulas
Boolean Combinations
Quantified Formulas
Quantifiers
Universal Quantifier
Syntax and Meaning
Scope of Quantification
Existential Quantifier
Syntax and Meaning
Scope of Quantification
Variable Binding
Free Variables
Bound Variables
Scope of Quantifiers
Variable Capture
Well-Formed Formulas in FOL
Formation Rules
Proper Quantifier Usage
Semantics of First-Order Logic
Structures and Interpretations
Definition of a Structure
Domain of Discourse
Interpretation Function
Variable Assignments
Assigning Values to Variables
Modified Assignments
Truth in a Structure
Satisfaction Relation
Truth for Atomic Formulas
Truth for Complex Formulas
Truth for Quantified Formulas
Semantic Concepts
Satisfiability
Validity
Logical Consequence
Logical Equivalence
Substitution
Substitution of Terms for Variables
Substitution Instances
Proper Substitution
Proof Systems for First-Order Logic
Natural Deduction for FOL
Quantifier Rules
Universal Introduction
Universal Elimination
Existential Introduction
Existential Elimination
Restrictions on Quantifier Rules
Proof Strategies with Quantifiers
Sequent Calculus for FOL
Quantifier Rules in Sequent Calculus
Eigenvariable Conditions
Resolution for FOL
Skolemization
Removing Existential Quantifiers
Skolem Functions
Skolem Normal Form
Herbrand Universe
Definition and Construction
Herbrand Base
Herbrand Interpretations
Unification
Unification Problem
Most General Unifier
Unification Algorithm
Resolution Rule for FOL
First-Order Resolution
Factoring
Completeness of Resolution
Decidability and Undecidability
Decidable Fragments
Monadic First-Order Logic
Two-Variable Logic
Undecidability Results
Church's Theorem
Undecidability of FOL
Semi-Decidability
Enumeration of Valid Formulas
Practical Implications
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3. Proof Systems for Propositional Logic
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5. Logic and Computation