At the start of the lecture, we introduce the "formal ingredients" of a game: the players, their strategies and their payoffs. Then we return to the main lessons from last time: not playing a dominated strategy; and putting ourselves into others' shoes. We apply these first to defending the Roman Empire against Hannibal; and then to picking a number in the game from last time. We learn that, when you put yourself in someone else's shoes, you should consider not only their goals, but also how sophisticated are they (are they rational?), and how much do they know about you (do they know that you are rational?). We introduce a new idea: the iterative deletion of dominated strategies. Finally, we discuss the difference between something being known and it being commonly known.

1. Introduction: Five First Lessons
2. Putting Yourselves Into Other People's Shoes
3. Iterative Deletion and the Median-Voter Theorem
4. Best Responses in Soccer and Business Partnerships
5. Nash Equilibrium: Bad Fashion and Bank Runs
6. Nash Equilibrium: Dating and Cournot
7. Nash Equilibrium: Shopping, Standing and Voting on a Line
8. Nash Equilibrium: Location, Segregation and Randomization
9. Mixed Strategies in Theory and Tennis
10. Mixed Strategies in Baseball, Dating and Paying your Taxes
11. Evolutionary Stability: Cooperation, Mutation, and Equilibrium
12. Evolutionary Stability: Social Convention, Aggression, and Cycles
13. Sequential Games: Moral Hazard, Incentives, and Hungry Lions
14. Backward Induction: Commitment, Spies, and First-mover Advantages
15. Backward Induction: Chess, Strategies, and Credible Threats
16. Backward Induction: Reputation and Duels
17. Backward Induction: Ultimatums and Bargaining
18. Imperfect Information: Information Sets and Sub-game Perfection
19. Subgame Perfect Equilibrium: Matchmaking and Strategic Investments
20. Subgame Perfect Equilibrium: Wars of Attrition
21. Repeated Games: Cooperation vs. the End Game
22. Repeated Games: Cheating, Punishment, and Outsourcing
23. Asymmetric Information: Silence, Signaling and Suffering Education
24. Asymmetric Information: Auctions and the Winner's Curse

This course is an introduction to game theory and strategic thinking. Ideas such as dominance, backward induction, Nash equilibrium, evolutionary stability, commitment, credibility, asymmetric information, adverse selection, and signaling are discussed and applied to games played in class and to examples drawn from economics, politics, the movies, and elsewhere.