Rules of inference
Channel: Douglas Weathers
Date: 2020-05-19

A rule of inference is a conditional statement that is always true. They can be proven with truth tables or verbally by appealing to established rules. We learn about two important ones: modus ponens and transitivity.

MISTAKES (sorta):
0:54 I read "p → q" as "p implies q," which is not totally wrong but I had just introduced ⇒ to mean "implies." (The statement p → q may be true or false; the statement p ⇒ q is true.) The subtitles read it as "if p then q" which, in context, is clearer.

Meant to be watched before or after reading Chapter 2 of the open source textbook Elementary Discrete Mathematics (https://dweathers.github.io/174/book.html).