CS 0441 Lecture Notes - Lecture 4: If And Only If, Existential Quantification, Peanut Butter

• School: Pitt
• Department: Computer Science
• Course: CS 0441
• Professor: William Garrison

Document Summary

Lecture #4 predicates and quantifiers: topics, predicates, quantifiers, logical equivalences in predicate logic, translations using quantifiers, propositional logic is simple, therefore limited, propositional logic cannot represent some classes of natural language statements. A propositional function p(x) has no truth value unless it is evaluated for a given x or set of xs: examples, assume p(x) x3 > 0. What are the truth values of the following expressions: P(-42: we can express the prime number property using predicate logic, predicates play a central role in program control flow and debugging, quantifiers allow us to make general statements that turn propositional functions into propositions. In english, we use quantifiers on a regular basis: All students can ride the bus for free: many people like chocolate. At least one person will sleep through their final exam: quantifiers require us to define a universe of discourse (also called a domain) in order for the quantification to make sense.