Lecture #5 looked at the use of logic to reason about an agent's environment.
Notes are available in four formats:
There is also a handout listing the natural deduction proof rules for propositional logic.
The lecture covered material from Chapter 7 of the textbook, more or less everything up until Section 7.5.2. (The textbook doesn't cover natural deduction).
If you have the textbook, go through the chapter up to that point.