When people have a disagreement that seems impossible to resolve, there are two time-honored solutions.
The first, rooted in the work of the famous 18th-century social theorist Edmund Burke, is minimalism. The second, rooted in the work of the obscure 17th-century social theorist George Savile, is trimming. Both played a big role in the fiscal-cliff deal. They are likely to prove relevant to negotiations over budget cuts, gun control and other upcoming battles.
Minimalists want to make agreement possible where it is necessary, while making agreement unnecessary where it isn't possible. They are content to leave important matters undecided. They know that people can agree on small steps when they are divided over large ones.
Minimalists focus on the questions they absolutely have to answer. In constitutional law, minimalist judges will be inclined to rule on a particular affirmative action program without resolving disputes about related programs.
Consider Chief Justice John Roberts' aphoristic summary of the minimalist position in constitutional law: "If it is not necessary to decide more to dispose of a case, in my view it is necessary not to decide more." Minimalists want to avoid the questions that most deeply divide people.
Minimalism plays an indispensable role in politics. A climactic (and accurate) scene in the movie "Lincoln" shows Thaddeus Stevens, a longtime defender of racial equality, assuring wavering Democrats by speaking in relatively minimalist terms about the 13th Amendment, declaring that it wouldn't guarantee full equality but only equality before the law. When negotiations over some of the biggest fiscal issues fell apart last month, President Barack Obama quickly moved in the direction of a minimalist solution, bracketing the largest questions and focusing narrowly on those issues on which agreement was both necessary and possible.
Trimmers are very differen. They don't want to leave things undecided. Instead they try to steer between the poles.
The idea of trimming comes from a small group of mostly forgotten thinkers in the late 17th century who were dismayed by the political polarization of their time. Savile, the most influential trimmer, insisted that "true Vertue hath ever been thought a Trimmer, and to have its dwelling in the middle, between the two extreams." To those who denounced the very word "trimmer," Savile asked, "Why, after we have played the foole with throwing Whig and Tory at one another, as boys do snowballs, doe we grow angry at a new name, which by its true signification might do as much to put us into our witts, as the others have been to put us out of them?"
Trimmers compromise, but don't favor compromise for its own sake. They try to identify and to preserve what is most essential, most valuable, and most deeply felt in competing positions. Their goal is to vindicate, at once, what they see as the most appealing aspects of seemingly antagonistic views. Chief Justice Roberts favors minimalism, but in the constitutional dispute over the Affordable Care Act he was a trimmer. He agreed with the conservatives that the Commerce Clause didn't support the act. He agreed with liberals that the act was constitutional under the taxing power of Congress.
With respect to gun control, trimmers would respect the individual right to have guns, not only because the Supreme Court has done so, but also because that right has become deeply ingrained in American culture and central to the lives and understanding of countless Americans. But trimmers would insist that the individual right isn't unlimited and that reasonable restrictions can be devised that are perfectly consistent with the Second Amendment.
The fiscal-cliff deal makes a series of compromises that trimmers would be willing to respect. It accepts Obama's argument for tax increases on the wealthiest Americans, but the threshold is higher than what he proposed, and the deal accepts much of the Republican position on the estate tax.
To be sure, minimalists and trimmers can make big mistakes. Insofar as it leaves important questions undecided, minimalism promotes uncertainty. A minimalist approach to current fiscal debates may be a serious blunder. Even an imperfect answer may be better than no answer at all.
Nor is trimming a philosophy for all seasons. Trimmers try to split the difference, so they may compromise with people who are wrong, confused or worse.
No sensible person celebrates minimalism or trimming as such. But sometimes one or the other is a practical necessity, and political life is unimaginable without them.
Cass R. Sunstein, the Felix Frankfurter professor of law at Harvard University, is a Bloomberg View columnist. He is the former administrator of the White House Office of Information and Regulatory Affairs, the co-author of "Nudge" and author of the upcoming "Simpler: The Future of Government."