Congress: A Political-Economic History of Roll Call Voting.

• Author: MUNGER, MICHAEL C.
• Position: Review

Congress: A Political-Economic History of Roll Call Voting By Keith Poole and Howard Rosenthal New York: Oxford University Press, 1997. Pp. xi, 297. $85.00 cloth.

This is the most important book on Congress written in the 1990s. Its presentation is flawed. I am not even sure it is a "good book" in the usual sense. But in terms of lasting importance, Keith Poole and Howard Rosenthal's Congress is a landmark.

In general, Pool and Rosenthal argue that the classical spatial model of politics doesn't explain real-world political conflict very well. The theory that voters weigh candidates' positions on many issues before choosing a candidate imposes unrealistic (and unnecessary) costs of information and search on voters. Somehow, issues get bundled and simplified. In Poole and Rosenthal's view, the bundling is achieved primarily through the competition among political parties.

That claim leads immediately to an apparently fatal problem (as I myself have often been told by my colleagues in political psychology): we have known for thirty-five years that individual belief systems are not consistent and are not constrained in the sense of obeying a set of ideological precepts (Phillip Converse, "The Nature of Belief Systems in Mass Publics," in Ideology and Discontent, ed. David Apter [New York: Free Press, 1964]). How can a simple "ideological" space describe political conflict if voters are not "ideological"?

The answer, it seems to me, has three parts. First, in terms of spatial theory, the answer is that constraint is imposed on voters by the institutions of aggregation, such as parties in competitive elections and a legislature in which a few parties elaborate a consistent and coherent message. "Constraint," in this sense, is imposed on voters, so that politics is ideological even if voters are not explicitly so. The intellectual history of this first step, as presented by Poole and Rosenthal, is interesting and important. The first person to argue formally that there are multiple spaces, including a complex multidimensional world of policy and a simplified "basic space" of politics, was Peter Ordeshook ("The Spatial Theory of Elections: A Review and Critique," in Party Identification and Beyond, ed. Ian Budge, Ivor Crewe, and Dennis Farlie [New York: Wiley, 1976]). That insight was developed further, with an explicit mechanism for moving from the politics to the policy, and vice versa, in later publications (Lawrence Cahoon, Melvin Hinich, and...