The Rational and the Reasonable: Social Choice Theory and Adjudication

42 Pages Posted: 21 Aug 2008

See all articles by Bruce Chapman

Bruce Chapman

Faculty of Law, University of Toronto

Date Written: 1994


This Article contends that the diversity of reasons chosen to rationalize different cases, even different cases within a given body of law, while evidencing contradiction to the legal skeptic, and arbitrary path dependence to the rational choice theorist, actually manifests law's overall reasonableness and coherence. The Article is organized as follows: Section I outlines the conventions of rational social choice that are relevant to this Article in both their preference-theoretic and their choice-theoretic forms. This Section also suggests a structural interpretation of these rationality requirements in terms of the general theory of the Good and in contrast to a general theory of the Right. Section II uses a simple abstract example to describe the very different notion of rationality that is inherent to legal reasoning across a set of "like cases", a form of reasoning that emphasizes the different relations between, rather than the comparable properties of, the various alternatives that are available for choice. This feature of legal reasoning explains the apparent partition- and path-dependence of judicial law making: the legal rule that is finally announced as rationalizing a set of cases depends on the sequence of choice over those cases. Legal reasoning is thus closer to theories of the Right, with their emphasis on process, than theories of Good, with their emphasis on the goals to be achieved in different end states. Section III illustrates the reasonableness of adjudication across a coherent set of like cases with an example taken from tort law. Finally, Section IV addresses the nagging question as to what possible advantage there could be, even for what the rational choice theorist hopes to accomplish, in law's reasonableness, that is, in the coherent yet path-dependent adjudication of a set of like cases. The Section argues, using an example based on Kaldor-Hicks efficient contracting and the cycle of social choice that it produces, that it is sometimes self-defeating to pursue a social goal directly and in a purely forward-looking way. The goal is often more likely to be achieved under the more coordinated set of choices made possible by a backward-looking (path-dependent) respect for prior choices.

Suggested Citation

Chapman, Bruce, The Rational and the Reasonable: Social Choice Theory and Adjudication (1994). University of Chicago Law Review, Vol. 61, p. 41, 1994. Available at SSRN:

Bruce Chapman (Contact Author)

Faculty of Law, University of Toronto ( email )

78 and 84 Queen's Park
Toronto, Ontario M5S 2C5
416-978-6911 (Phone)
416 978 2648 (Fax)

Here is the Coronavirus
related research on SSRN

Paper statistics

Abstract Views
PlumX Metrics