How much would you sacrifice to help your political party? When the news reports long lines at the polls, some voters persevere and some stay home. Similarly, when the party’s leaders falter—abandon principles, mishandle a crisis, commit crimes—some members endure the shame and carry on, while others turn against the leaders. Citizens also make tradeoffs to hurt the opposing party. When the opponents take our rights and flout our values, some citizens charge in protests while others cautiously let the anger pass. What’s the difference, and how do people make these tradeoffs?
The answer, we suggest, is found in ratios, like the ones in music, painting, and mechanics. The ratios for parties are in the citizen’s mind: the ratio of the cost to the person compared to the benefit to the party. It’s the price you would pay to help or hurt a party, not only in dollars but also in time, effort, danger, and reputation. The mind uses this ratio to make tradeoffs, so it may be called a welfare tradeoff ratio, or tradeoff ratio, for short.
Tradeoff ratios are distinct from the mental processes found in traditional theories of partisanship, including theories rooted in attachment, identity, self-interest, attitudes, heuristics, and irrational emotions. For instance, theories about irrational attachments to a group do not say how these attachments factor into tradeoffs; the attachment would need to be a quantity stored in the mind if it is to be weighed against other quantities. The closest theories are about social preferences, such as preferences for fairness, altruism, and punishment. But tradeoff ratios are not general preferences that someone applies to everyone. We have specific ratios for each person and group, and they change as our relationships change.
The idea of tradeoff ratios comes from previous research on the psychology of interpersonal cooperation. The mind has special psychological abilities for making decisions that affect other people. Friends decide whether to help each other, parents decide how much to sacrifice for their children, and leaders decide whose interests to prioritize. To make these choices, the mind intuitively computes how much it is worth to help or hurt specific individuals, summarized by a cognitive variable, the tradeoff ratio. These computations are mostly unconscious, automatic, quick, and effortless, like the mind’s computations of color, depth, or the meaning of speech. People experience these computations as vague feelings, but the underlying cognition is precise and sophisticated, again like vision and language. To guide decisions, the mind uses tradeoff ratios to weigh another person’s welfare compared to our own.
So is helping political parties like helping people? To find out, we conducted experiments in which participants decided whether to sacrifice their own money to give or take money from a party. They made dozens of these decisions with varying costs in a random order. We wanted to know whether participants would make choices that are consistent with a distinct tradeoff ratio for each party, rather than choosing haphazardly based on vague feelings. In two experiments, participants’ tradeoffs were highly consistent with a distinct ratio (~90% consistent on average), despite making dozens of decisions in a random order. Moreover, participants’ ratios correlated in the expected directions with partisanship, political ideology, and feelings of enthusiasm and anger toward each party, corroborating that these ratios are politically meaningful.
In general, over 90% of partisans helped a party at a cost to themselves. And a substantial minority sacrificed money to spite their own party, illustrating the tension that some citizens feel toward their own party. Roughly 40% paid a cost (usually smaller amounts) to help the outparty, suggesting that these citizens feel at least some generosity toward both parties. At the other extreme, a quarter to a third of participants would pay any amount to harm the outparty, up to the maximum of sacrificing $100 to prevent the party from gaining $50 (more specifically, the chance of winning these amounts in a lottery). Overall, these findings echo other research finding that a fraction of polarized Americans coexists with a majority of moderate citizens.
These findings may help transcend the traditional debates about whether voters are rational or irrational. Instrumental theories of partisanship emphasize narrow self-interest, but participants’ altruism and spite clearly contradict this idea. Expressive theories emphasize emotions and social identities, perhaps even suggesting that attachment to parties is irrational and uncalculating, which implies that people’s quantitative tradeoffs will be disordered and haphazard since they do not benefit from the precision of calculations. But in fact, participants’ tradeoffs remained highly consistent with a distinct cost-benefit ratio, even when challenged to make many tradeoffs in a random order. Participants’ altruism and spite toward parties were proportional to the costs and benefits, revealing that their tradeoffs did result from precise calculations, even if they didn’t maximize their own money.
Thus, people’s partisanship may be rational in the sense of proportional to costs and benefits, rather than in the narrow sense of maximizing money. This idea echoes growing research in psychology finding that many emotions, including anger, compassion, fear, and disgust are regulated by precise (unconscious) calculations, which proportion our emotions to costs and benefits, such as more anger for more harm, more compassion for more need, and more disgust for more risk of pathogens. Underneath the turbulent surface of partisan passions hide precise calculations that proportion our altruism and spite toward parties.
Fascinated by ratios of all kinds, Leonardo da Vinci wrote in his notebook, “Proportion is not only found in numbers and measurements but also in sounds, weights, times, spaces, and in whatsoever power there may be.” Partisanship may be among the powers of society governed by proportions in the citizen’s mind.