on March 28, 2005
The Calculus of Consent, written by James M. Buchanan and Gordon Tullock, is one of the founding publications of what has since become known as the subdiscipline of public choice, which is the application of tools of economic analysis to the domain of political decision making. In theory, political decisions are made by elected officials in their pursuit of the "general interest" or the "common good", however defined. In reality, however, political decisions reflect the outcome of the workings of a number of interested parties, which includes voters, politicians, career government officials (bureaucrats), special-interest groups, lobbyists, etc., each of whom have their own agendas and interests. When someone appeals to the public interest while making a political argument, more often than not the underlying motive is a matter of self-interest (e.g. teachers' unions angling for larger teacher salaries under the pretext of improving public education). Public choice theory does not mean to be critical or cynical about this. Instead, it is merely intended to be descriptive: that's simply the way the political decision-making process works, and we need to understand this first before we try and improve the world through politics. For his central role in the development of public choice theory, professor Buchanan would go on to earn the 1986 Nobel prize in economics.
The book's main contribution lies in its development of the analysis of political behavior, particularly so-called logrolling (i.e. vote-trading, or political exchange). The Founding Fathers set up our political system in order for the general interest to be served rather than interests that only benefit specific groups at the expense of the rest of the population. But elected officials have learned to circumvent that intent by happily trading their vote on issues on which they don't care one way or the other in exchange for votes on issues about which they do care. All members of the legislature end up voting for each other's pet projects, which all get enacted at taxpayers' expense.
The authors propose that one solution would be to distinguish between legislative rules and constitutional rules. Legislative (statutory) rules may be adopted by simple majority coalitions pursuing their own interests. Constitutional rules, on the other hand, are supposed to be decided on without regard for short-term individual consequences ("what is right in the long run?" instead of "what's good for me today?"). Legislative rules are substantive, constitutional rules are procedural. Constitutional rules are meant to restrict abuse of the legislative process by majority coalitions. The difference between legislative and constitutional rules is perhaps somewhat idealistic. After all, what's to prevent people from voting for or against constitutional rules based on their short-term interest. In theory, people are thought to realize that "what's right" will also benefit them, as everyone else will be bound by the same rules, but in practice it doesn't always quite work that way (e.g. people may be aware that a constitutional balanced budget amendment is the morally right thing to do to prevent saddling their descendants with public debt, but as of yet no such amendment has been enacted). Still, the legislative-constitutional distinction is at least helpful as an analytical device.
As the authors acknowledge, in real life things aren't always quite as black-and-white as they have here been described. Sometimes people--yes, even some politicians--vote according to their conscience rather than according to their own self-interest. But the insights and analysis offered by the book and by public-choice theory more often than not do apply. The book is highly persuasive in demonstrating that democracy's simple-majority voting rule (50 percent plus one vote) does not inherently lead to superior decisions. For example, it offers a convincing explanation for why even in majoritarian democracy, taxes and government spending, whether on public services or on redistribution, are clearly "too large", i.e. larger than the vast majority of Americans would agree to if they were to redesign and rebuild government all over again from scratch today.
Stylistically, the book is light on math and the authors have an elegant writing style. But it is somewhat on the academic side and rather heavy on preliminaries. More comprehensive and more easily digestible treatments of issues of political decision making in a democratic context do exist, but even now, some four decades after its initial publication, the book is still considered a classic work in the history of economics and political organization. Its central section is "a simple logrolling model" (pp. 136-142 in the Buchanan Collected Works edition).