PE3101P: Decision and Social Choice

Semester 1, AY2026/27 — Department of Philosophy, National University of Singapore.

Lecture: Thursdays 14:00–16:00, AS1-0203.
Tutorials (weeks 4, 6, 8, 10 and 12):

• TE1: Fridays 10:00–12:00, AS2-0311.
• TE2: Tuesdays 14:00–16:00, AS3-0215.

Course description

Decision-making is straightforward when we know exactly what will happen depending on what we choose and only one person’s preferences are at issue. But very few decisions are like that. This course concerns rational decision-making when we are uncertain of the outcomes of our actions (decision theory) and when we need to reconcile differing preferences within a group of people (social choice theory).

Course materials

• Syllabus
• Textbook: Wolfgang Schwarz, Belief, Desire, and Rational Choice (2022) — referred to as “BDRC”.
• Sets and Mathematical Proofs: A Primer — an introduction to naive set theory and to writing proofs. Also available as a PDF.

Exercise sheets and solutions

• Optional exercises (Week 1) and solutions — not assessed.
• Tutorial exercises 1 and solutions — (weeks 1–3); not assessed.
• Optional exercises (Week 4) — not assessed.
• Optional exercises (Week 5) — not assessed.

Assessment

• Assignment 1 (Solutions) — due Tuesday 8 September 2026, 23:59. Worth 20% of the final grade; covers weeks 1–3.
• Optional templates to write your answers into: Word or LaTeX — you are not required to use either. The LaTeX one can also be opened as a new Overleaf project, which needs nothing installed and gives you your own copy to edit.

Week 1 — Introduction

Thursday 13 August 2026.

• Lecture notes
• Slides
• Reading: BDRC chapter 1 — not compulsory for week 1.

Week 2 — Probability

Thursday 20 August 2026.

• Lecture notes — html version (recommended) or pdf version.
• Slides
• Reading: BDRC chapters 2–3.

Week 3 — Newcomb's problem

Thursday 27 August 2026.

• Lecture notes — html version.
• Slides
• Reading: BDRC chapter 9.
• Reading: Adam Elga, “Newcomb University: A play in one act” (2020) — (I recommend reading this first)

Week 4 — Expected utility theory

Thursday 3 September 2026.

• Slides
• Reading: BDRC chapter 6.
• Reading: BDRC chapter 5 — recommended, but optional.

Week 5 — Money pumps and dynamic choice

Thursday 10 September 2026.

• Slides
• Reading: Johan E. Gustafsson, Money-Pump Arguments (Cambridge University Press, 2022), chapters 1–2 — open access (CC BY 4.0).
• Reading: BDRC chapter 8 — recommended, but optional.