# Section 2.3 - Truth Tables and Equivalence

In this series of lectures, we're going to do one of the things that mathematicians always like to do when they come up with a new kind of object like our propositional statements: We're going to look for ways to tell when two compound statements are equal or, in the language of mathematical logic, when they're equivalent.

# Videos

### Lectures

In this lecture, we're going to look at two special types of truth tables: ones that are always true (tautologies) and ones that are always false (contradictions). (lecture slides)

Now that we know how to evaluate when a statement is true and when it's false we have a basis for comparing them or, in logical terms, deciding when they're equivalent. (lecture slides)