Reading Orin Kerr’s new paper outlining an “equilibrium-adjustment theory” of the Fourth Amendment, I found myself reflecting on how thoroughly the language of “balancing” pervades our thinking about legal and political judgment. The very words “reasonable” and “rational” are tightly linked to “ratio”—which is to say, to relative magnitude or balance. We hope to make decisions on the basis of the weightiest considerations, to make arguments that meet their burden of proof. We’re apt to frame almost any controversy involving heterogenous goods or values as a problem of “striking the right balance” between them, and many of those value dichotomies have become well worn cliches: We’ve all seen the scales loaded with competing state interests and individual rights; with innovation and stability; with freedom and equality; with privacy and security. There’s obviously something we find natural and useful about this frame, but precisely because it’s so ubiquitous as to fade into the background, maybe it’s worth stopping to unpack it a bit, and to consider how the analogy between sound judgment and balancing weights may constrain our thinking in unhealthy ways.

Perhaps the most obvious problem with balancing metaphors is that they suggest a relationship that is always, by necessity, zero sum: If one side rises, the other must fall in exact proportion. Also implicit in balancing talk is the idea that equilibrium is the ideal, and anything that upsets that balance is a change for the worse. That’s probably true if you’re walking a tightrope, but it clearly doesn’t hold in other cases. If you have a perfectly balanced investment portfolio and somebody gives you some shares of stock, the balance is upset (until you can shift some assets around), but you’re plainly better off—and would be better off even if for some reason you couldn’t trade off some of the stock to restore the optimal mix.

In my own area of study, the familiar trope of “balancing privacy and security” is a source of constant frustration to privacy advocates, because while there are clearly sometimes tradeoffs between the two, it often seems that the zero-sum rhetoric of “balancing” leads people to view them as always in conflict. This is, I suspect, the source of much of the psychological appeal of “security theater”: If we implicitly think of privacy and security as balanced on a scale, a loss of privacy is ipso facto a gain in security. It sounds silly when stated explicitly, but the power of frames is precisely that they shape our thinking without being stated explicitly.

There’s a deeper problem, though: Embedded in the idea of the scales is a picture of a process for arriving at sound decisions—which if the metaphor is sufficiently pervasive we may come to think of as the only method for making sound decisions. A scale is a machine for reducing diverse objects—or in the metaphor, interests and values—to a single shared dimension. You might have items as varied as toasters and giraffes on the opposing plates of the scale, but all the scale cares about—or all we care about when we employ it—is that they both have weight and mass. Every other difference between the items in the balance is irrelevant so long as they have this one shared property, this one dimension along which they intersect, which allows us to quantify each in terms of the other.

If you think about the cases in which we employ balancing rhetoric, though, it’s often unclear just what this shared dimension is supposed to be. Sometimes that implicit dimension seems to be the universal currency of happiness or utility—the ultimate good that more concrete values like privacy or utility are presumed to serve. But often the imaginary scales conjured by balancing talk conceal the fact that we don’t have a clear sense of what that shared dimension is supposed to be, what single quantity is supposed to serve as our standard for comparing such heterogenous goods. The jurist or political philosopher who assumes a scale—perhaps without realizing he’s doing so—may be rather like the economist in the old joke who begins by assuming a can opener.

Paradoxically, this may make disagreement seem more intractable than it really is. We often say that even when people are agreed on the facts, they may “assign different weights” to competing values, which if we really did have a single agreed upon scale or dimension along which to balance, could only be understood as some kind of irreducible brute preference.

The distortion is magnified if the values we hope to “weigh” are not just qualitatively different from each other, but internally plural or diverse. Legal scholar Dan Solove, for instance, argues forcefully that “privacy” is not a monolithic value defined by any singular essence, but a cluster concept defined instead by overlapping family resemblances. (The classic example from Wittgenstein is the idea of a “game,” instances of which range from football to chess to Myst to the unstructured pretend-play of Cops and Robbers.) In Solove’s schema, privacy encompasses an array of quite different interests: Colloquially speaking, we recognize that one’s privacy may be violated by physical intrusion on the seclusion of the home, by the disclosure of sensitive or embarrassing personal facts, by the denial of autonomy to make intimate medical or sexual decisions, by the mere knowledge that one’s actions (even one’s “public” actions) are being systematically monitored and recorded, by having one’s image (again, even an ordinary photograph snapped on a public street) plastered on billboards and television without one’s consent. The point is not, of course, that the law should forbid all these things; merely that we find it perfectly intelligible to describe each as, in some sense, an incursion on privacy.

Even bracketing the zero-sum framing problem, think about how squeezing all these dimensions of privacy on to a unidimensional metaphorical scale tends to flatten the debate, at least outside the context of the scholarly journals inhabited by folks like Solove. Obviously, we need to use shorthand terms like “privacy” and “security” to keep discussion manageable, but is it really especially illuminating to treat every proposed security measure as though its consequences can be reduced to quantity subtracted from an undifferentiated lump of privacy stuff, and a quantity added to a blob called security? The task of analysis is always aided when we can render heterogeneous interests more easily comparable by reducing them to some uniform measure, of course, but balance metaphors imply that we’ve already achieved this. This may be why so many legal opinions employing “balancing tests” feel so thin, and so many arguments about where to “strike the right balance” between competing values founder. The metaphor assumes a lot of analytic background work that hasn’t actually been done—and conceals the fact that it still needs to be.