If you are watching the World Cup without a favorite team, economist Dean Karlan can help. In a post on the New York Times’ Upshot blog, Karlan makes the case that you should root for the country whose victory would “produce the largest aggregate increase in happiness.” His utilitarian formula for aggregate happiness uses population size, the country’s interest in soccer, and level of poverty (on the theory that windfalls such as World Cup victories bring more happiness to those lower on the utility curve).

This is a fun way for Karlan to bring attention to the point that economics is about “how to create the most good with limited resources,” and to argue for allocating resources to the poorest countries whenever possible (in charitable giving, for example). But the piece also demonstrates how the ethics of being a sports fan challenge our intuitions about utility and self-interest.

Karlan’s index assumes that the utility of a World Cup victory is limited to denizens of the winning country. This is reasonable, but it doesn’t account for the fact that the Cup is followed intensely by millions of people in countries that are not even competing in Brazil (and the elimination rounds will be watched by millions more whose teams have already been knocked out). Some may be watching for the pure thrill of high-level athleticism, but others will—like sports fans everywhere—develop secondary rooting interests based on underdog status, geographic proximity, or affection for specific players. It wouldn’t be surprising, for example, if some fans in Africa or Asia were to root for their continents’ few representatives to bring home the first ever Cup won by a country outside of Europe and South America. (If so, all the better for Nigeria, the team Karlan recommends supporting.)

Sports are an excellent tool for thinking through tricky ethical and political questions.

On the flip side, losses can bring some utility, too: rooting against certain teams can be just as rewarding as rooting for your favorites—something I know well as a fan of the Boston Red Sox, a team whose loyalists spent decades consoling themselves by celebrating New York Yankees losses. Cup-watchers who opt for Schadenfreude can choose between hating on Uruguay and tournament heel Luis Suarez, rooting against the favored Brazilians, or indulging geopolitical grievances against local rivals or the world’s only superpower.

Incorporating these factors—cross-national solidarity and dislike—into utility calculations would be difficult but not impossible from an economic standpoint. Outside the realm of economics, though, is the question of whether cheering for one team over another is a morally neutral preference, like having a favorite color, or something more complicated. Maybe indulging grudges is dangerous, if only by rooting against a rival; maybe it risks deepening the sense of division, habituating us to hatred, and jading us. Alternatively, it could be a harmless way to let off some jingoistic steam. Maybe cheering against the United States is a reasonable expression of frustration at American arrogance and hegemony, or maybe it’s emblematic of a resentful and dangerous worldview. Perhaps even positive rooting can be dangerous, especially if it reinforces excessive nationalism or racialized worldviews. Or maybe seeking joy in sports fandom is a dead end and we’d all increase our welfare in the long run by devoting the time we would have spent watching the Cup to learning to enjoy opera. Debating these questions brings deep political and ethical commitments into play.

Perhaps sporting affiliations seem like a trivial topic for philosophical argument, but I bring it up because it helps us think about the role of individual preferences in politics. Most arguments about maximizing well-being assume that individuals have some exogenous, preexisting set of preferences that policymakers should try to satisfy. That allows for relatively straightforward debates about the tradeoff between efficiency (should we try to maximize aggregate wealth or happiness?) and equity (should we try to make sure that everyone achieves some minimal level of wealth or happiness?).

Once we stop treating preferences as though they are set in stone, though, questions of morality and policy rapidly become very complicated. Now we have to consider qualities such as virtue (what sort of team or player should we admire?), loyalty (are we obligated to continue rooting for the team or country we’ve always supported?), and solidarity (should we cultivate our ability to take pleasure in others’ joy?). In principle, all of these qualities could be incorporated into the argument for maximizing happiness; it could be argued, for example, that a world in which underdogs have hope (go Costa Rica!) will produce more happiness in the long run than a sixth championship for Brazil. But when it comes to making moral and political decisions, this is a lot messier than assuming that preferences are constant and not open to debate.

The complexity of these questions may sound like an argument against a utilitarian approach to politics, but it is quite the opposite. Anti-utilitarians tend to present hypotheticals in which achieving the greatest good for the greatest number seems abhorrent (e.g., having someone torn apart by lions for the entertainment of the masses). Treating preferences not as given but as changeable helps respond to those hypotheticals, since it lets us consider the long-run implications—would instituting human sacrifice as entertainment actually maximize happiness in the long run?—instead of the one-off gain in utility. The same principle applies to less fanciful debates, such as whether we have an obligation not to patronize sports, like American football, that have devastating consequences for their participants.

Karlan’s piece illustrates why sports are an excellent tool for thinking through tricky ethical and political questions. The stakes of his argument are so transparently low (because our rooting choices have no effect on the outcomes of the games) that it makes it easier to think analytically about the serious questions he poses. Moreover, since the utility we derive from sports fandom is fundamentally arbitrary—why care which group of athletes you’ve never met comes out on top?—arguing about it in moral terms can help us consider carefully why we value what we value. I don’t expect that many fans’ loyalties will actually be swayed by ethical debates, of course—but unfortunately, that is yet another thing sports have in common with politics.