Paige Amormino, Adam Kagel, Joanna Li and Abigail Marsh
Affiliation: Georgetown University, University of California at San Diego, Georgetown University, Georgetown University
Category: Psychology
Keywords: altruism, impartiality, moral values, moral psychology, social psychology
Date: Friday 5th of September
Time: 14:30
Location: Room 154 (154)
View the full session: Morality & Social Cognition
For centuries, religious, philosophical, and moral traditions have lauded impartial altruism as a noble ideal, framing universal love and unbiased goodwill as core virtues. Contemporary movements such as effective altruism echo this perspective, encouraging donations and interventions that help those in greatest need, regardless of proximity or personal connection. Nevertheless, actual impartial altruism remains relatively uncommon, with typical giving patterns favoring close friends and family more than distant individuals.
Social scientists have documented consistent “social discounting,” wherein individuals become less generous as social distance grows. This pattern is widely accepted as normative and, in everyday life, is often reinforced by expectations that people should prioritize their loved ones over those who are less familiar. Further, studies that present hypothetical scenarios have shown that most observers perceive highly impartial individuals—those who treat a distant stranger and a close friend similarly—as less warm or less trustworthy. Hence, it has been hypothesized that impartial altruism may be atypical because it threatens valued personal bonds and leads others to judge impartial individuals negatively.
However, laboratory and self-report methods cannot fully capture real-world behaviors involving significant costs or risks. Acts such as altruistically donating a kidney to a stranger offer a concrete opportunity to observe whether people whose actions are consistent with impartial altruism enjoy the same level of close social connections as those with more typical giving patterns. Altruistic kidney donors have been shown to treat distant recipients with substantially greater generosity in lab tasks; they also appear to perceive the suffering of strangers in ways that are broadly similar to how they perceive the distress of close others. Yet, the question remained whether these extraordinary altruists sacrifice valued social bonds in exchange for helping strangers.
To investigate this possibility, we tested whether impartial altruists actually experience diminished relationship quality with their closest friends and family. We also explored whether donors’ partners themselves exhibit impartial generosity, suggesting “value homophily,” in which people with similar moral perspectives form or maintain close bonds. If donors do indeed pair with like-minded partners, then they might preserve robust relationships because those close to them share, rather than resent, their impartial values.
To measure impartial altruism directly, we adapted the familiar social discounting task—where participants typically choose between keeping money for themselves or splitting it with another person at varying social distances—into a “third-party social discounting task.” Our new version asks participants to distribute resources between a close other (e.g., a spouse, sibling, or friend) and a more distant individual. This forces a direct choice between partiality and impartiality. Past tasks often emphasize self-versus-other generosity, which cannot fully capture how people respond when they must weigh two others’ needs, one close and one distant.
We enrolled 59 altruistic kidney donors plus their nominated closest partner, as well as 71 demographically matched controls plus their closest partner. After reporting demographic details, each person completed two behavioral tasks: the first-person social discounting measure and the third-party social discounting paradigm. They also answered questionnaires on moral beliefs (including universal beneficence and moral tolerance) and on relationship quality (e.g., warmth, reliability, closeness). Our central question was whether donors would show heightened impartial altruism in the third-party task and, if so, whether that impartiality negatively affected the quality of their close relationships.
Results supported two main conclusions. First, in line with prior findings, altruistic kidney donors again displayed reduced social discounting in the first-person task, extending generosity toward distant individuals more than controls did. More importantly, donors demonstrated significantly greater impartiality in the third-party paradigm: they were more likely to split resources evenly between a close partner and a distant individual. This pattern suggests donors genuinely prioritize fairness, rather than directing a disproportionate share to those they love most.
Second, we found no evidence that heightened impartiality undermines donors’ close relationships. Using measures of relationship satisfaction and affection, we observed no significant differences in closeness, warmth, or reliability between donor dyads and control dyads. This finding runs counter to the assumption that impartial altruism causes conflict or dissatisfaction, implying that donors who treat distant others generously are not harming their partners.
A likely explanation emerged in our data on donors’ partners: they too displayed lower social discounting than did partners of controls. Donors’ partners were more willing to allocate resources to distant individuals, suggesting strong moral alignment between donors and their closest companions. Instead of having an impartial altruist paired with someone who demands special treatment, both partners shared a universalist outlook. This “value homophily” appears to protect their relationship from tension that might arise if only one person favored distant strangers.
We further explored which factors might drive donors’ impartiality. We tested explicit beliefs about moral relativism, moral tolerance, and endorsement of universal beneficence, as well as whether donors assume others share their own generosity (consensus bias). Surprisingly, self-reported moral beliefs did not consistently predict third-party allocations, whereas donors’ first-person generosity correlated strongly with their decisions on behalf of close and distant others. This pattern suggests that impartial altruism reflects a broader, stable trait rather than conscious moral reasoning alone. Donors may default to treating others, close or distant, as they treat themselves.
Our findings clarify why impartial altruism need not undermine personal ties. Laboratory experiments using hypothetical dilemmas often show observers rating impartial actors as less warm or desirable, perhaps because observers believe special obligations to loved ones should override distant needs. In real life, donors may maintain fulfilling partnerships simply because their partners hold similar attitudes. Neither party sees impartial giving as neglectful; instead, both value fairness across social distances. This shared perspective likely cements, rather than erodes, their bond. Our results indicate that moral ideals of universal compassion can thrive alongside healthy, committed relationships, given the right compatibility in values.