## Belief, Desire, and Rational Choice (Autumn 2022)

This course is an introduction to formal models of belief, desire, and rational choice. It has roughly three parts. The first introduces the core ideas of Bayesian epistemology, where belief is treated as an attitude that comes in degrees. The second part studies formal models of value or desire, drawing on utility theory in economics and value theory in philosophy. The third part looks at how beliefs and desires guide rational action, going through some basic issues in Bayesian decision theory.

No prior knowledge of the material is expected, beyond familiarity with elementary arithmetic and propositional logic.

### Course Organiser

Dr Wolfgang Schwarz (wolfgang.schwarz@ed.ac.uk)

Office hours: Friday 11:00--12:00 and by appointment

My office is room 8.06 in 40 George Square

### Course Secretary

Peter Cruickshank (philinfo@ed.ac.uk)

### Classes

**Undergraduate seminars:**

Monday 13:10--14:00, Dugald Stewart Building, room 1.20

Wednesday 13:10--14:00, Dugald Stewart Building, room 1.17

**Postgraduate seminars:**

Monday 10:00--10:50, Dugald Stewart Building, room 1.17

Wednesday 10:00--10:50, Appleton Tower, room 2.11

### Format and Assessment

The course is based on an online textbook, whose chapters will appear in the syllabus below. (You can take a look at the last version of the full textbook at wolfgangschwarz.net/bdrc/bdrc.pdf, but the content will change this year, so do pay attention to what I upload to the syllabus!)

You are expected to work through each week's chapter *in advance*,
before the Monday seminar. Each chapter contains exercises, which you should try
to answer (on paper, with your student number at the top). I will collect your
answers at the start of the seminar on Monday. The exercises determine 50% of
your mark.

The remaining 50% of your mark are based on a final essay of up to 1500 words, due by Thursday, 8 December for UG students, and by Thursday, 15 December for PG students. Suggestions for essay questions can also be found in the textbook.

### Readings

The only required reading is the online textbook, whose (revised) chapters will appear in the syllabus below.

Supplementary reading for the whole course:

- Jonathan Weisberg: Odds and Ends (2021)
- Katie Steele and H. Orri Stefansson: "Decision Theory" (2020)
- Lara Buchak: "Decision Theory" (2016)
- Michael Strevens: Notes on Bayesian Confirmation Theory (2017)

## Syllabus

### Week 1 (19/09): Overview

How beliefs and desires are related to choice; why beliefs and desires are graded; the difference between conceptual analysis and model-building.

Core reading: **Chapter 1 (PDF).**

### Week 2 (26/09): Belief as probability

Basic rules of probability; Bayes' theorem; some applications.

Core reading: **Chapter 2 (PDF).**

### Week 3 (03/10): Probabilism

The betting interpretation of belief; Dutch Book arguments; declining marginal utility; comparative credence.

Core reading: **Chapter 3 (PDF).**

### Week 4 (10/10): Further constraints on rational belief

Belief and perception; conditionalization; indifference; probability coordination; confirmation.

Core reading: **Chapter 4 (PDF).**

### Week 5 (17/10): Utility

Two conceptions of utility; sources of utility; utility and credence; the formal structure of utility; basic desire.

Core reading: **Chapter 5 (PDF).**

### Week 6 (24/10): Preference

The ordinalist challenge; deriving utility and credence from preference.

Core reading: **Chapter 6 (PDF).**

### Week 7 (31/10): Separability

The composition of value; additivity; discounting.

Core reading: **Chapter 7 (PDF).**

### Week 8 (07/11): Why maximize expected utility?

Arguments for the MEU principle; dynamic decision theory; risk; localism.

Core reading: **Chapter 8 (PDF).**

### Week 9 (14/11): Evidential and Causal Decision Theory

Newcomb's problem; EDT vs CDT.

Core reading: **Chapter 9 (PDF).**

### Week 10 (21/11): Game theory

Core reading: **Chapter 10 (PDF).**

### Week 11 (28/11): Bounded rationality

Core reading: **Chapter 11 (PDF).**