A Mini-Course on Judgement Aggregation and Group Agency
Join Christian List, Visiting Professor of Law at Harvard Law School, and Professor of Political Science and Philosophy at the London School of Economics for a Mini-Course on Judgement Aggregation and Group Agency.*
The free course is open to all interested law students, graduate students, postdocs, and faculty (both at Harvard Law School and surrounding universities). NO preparatory reading or prior familiarity with the topics is necessary.
*The course sections complement each other, but are individually self-contained, so participants can attend ONE or ALL of the sessions.
When: Friday, November 6, 2015
Where: Griswold Hall Room 110, Harvard Law School
Time: 10:30 a.m. – 4:45 p.m.
**In the comments section, please indicate if you will be joining us for lunch.**
Walk-in attendees are still welcome.
The three-part course will focus on two questions:
1. How can the judgments of several individuals (e.g., judges, experts, committee members, jurors, or voters) be aggregated into overall collective judgments?
2. Can collectives be intentional agents (“subjects”) in their own right, and if so, under what conditions?
Schedule of Events:
Check-in
10:30 a.m. – 11:00 a.m.
Session 1: The Democratic Trilemma
11:00 a.m. – 12:30 p.m.
In this session, I will introduce the social-choice-theoretic way of thinking via what I call the “democratic trilemma”. The 18th century thinker Nicolas de Condorcet famously observed that majority rule sometimes produces inconsistent outcomes (this observation was later generalized in Kenneth Arrow’s influential work). Revisiting Condorcet’s insights from a fresh perspective, I will show that there is a conflict between three initially plausible requirements of democracy: “robustness to pluralism”, “basic majoritarianism”, and “collective rationality”. No decision procedure can generally meet these three requirements at once; at most two can be met together. This trilemma raises the question of which requirement to give up. Since different answers to this question correspond to different views about what matters most in a democracy, the trilemma suggests a map of the “logical space” in which different conceptions of democracy are located.
Indicative background paper: “The Logical Space of Democracy”, Philosophy and Public Affairs 39(3): 262-297, 2011
Lunch
12:30 p. m. – 1:30 p.m.
Session 2: From the Doctrinal Paradox to the Theory of Judgment Aggregation
1:30 p. m. – 3:00 p.m.
How can a multi-member group ensure that its collective judgments are internally consistent? Recent work on this question was prompted by a paradox in jurisprudence, the “doctrinal paradox”. Suppose a collegial court has to make a decision on some conclusion (“is the defendant liable?”) on the basis of several premises (“was there a valid contract?”, “was there a breach?”), where the premises are jointly necessary and sufficient for the conclusion (i.e., “liability if and only if contract and breach”). It can then happen that each premise is supported by a majority of judges while the conclusion is not. As a result, the court’s overall judgment will depend crucially on the voting protocol used. I will explain how the doctrinal paradox is just the tip of the iceberg of a more general impossibility result, and I will introduce a formal framework in which this result can be developed and assessed. I will present this material in a relatively non-technical way (though the theory to be introduced is a technical one).
Indicative background paper: “The Theory of Judgment Aggregation: An Introductory Review”, Synthese 187(1): 179-207, 2012
Break
3:00 p. m. – 3:15 p.m.
Session 3: Collective Intentions and Group Agency
3:15 p. m. – 4:45 p.m.
We often ascribe intentions, such as beliefs or preferences, not just to individuals, but also to collectives. We speak of the opinion of a jury, the preferences of the electorate, the commitments of Amnesty International, and the intentions of British Petroleum as it engages in oil drilling. Are such ascriptions of intentions and even agency to collectives purely metaphorical? Or can collectives truly have intentions? Can they even qualify as agents or subjects in their own right? In this third session, I will introduce a theoretical framework for thinking about these questions and explain why it is helpful to distinguish between three different kinds of collective attitudes: “aggregate attitudes”, “common attitudes”, and “corporate attitudes”. The framework allows us to identify the conditions under which groups can plausibly be viewed as actors in their own right.
Indicative background paper: “Three kinds of collective attitudes”, Erkenntnis 79(9): 1601-1622
If you have further questions, please contact the HLS Office of Academic Affairs at 617-496-1696 or email llangone@law.harvard.edu