A debate is currently unfolding in Germany around former Health Minister Jens Spahn, who had publicly opposed commercial surrogacy but became a parent through surrogacy abroad. Much of the public discussion has focused on whether his decision was hypocritical. But the episode points to two more general questions: what makes people consider a transaction morally unacceptable in the first place, and do we judge such transactions differently once we are personally involved rather than observing them from the outside?
Surrogacy is only one example. Should people be allowed to sell a kidney? Should workers be free to accept unusually risky jobs? Although such transactions may benefit everyone involved, many people believe they should nevertheless be prohibited. Two recent studies by BSoE researchers Hande Erkut and Dorothea Kübler examine what makes transactions repugnant and why people sometimes disagree about them.
Studying real-world markets alone cannot reveal what drives repugnance because they differ in many ways at once. Two features are often thought to play a central role. The first is the severity of the consequences for the vulnerable party, such as the health risks associated with selling a kidney. The second is agency: whether the vulnerable party has a meaningful opportunity to refuse the transaction or is effectively left with no choice because of poverty, coercion, or other circumstances. To isolate these factors, the researchers designed a laboratory experiment in which one person could offer another money to take over an unpleasant experience. The experience was either relatively mild or more severe, and the recipient either had a genuine right to refuse or did not.
The results showed that repugnance is driven by the combination of severe consequences and limited agency. Neither factor alone was enough to make most people reject a transaction. The researchers then extended their analysis to a vignette study with participants living in Germany, who evaluated two real-world controversial markets: kidney sales and commercial surrogacy. The findings for kidney sales mirrored those from the laboratory, suggesting that the mechanisms identified in the experiment also help explain judgments about real-world markets. The study also revealed that participants distinguished sharply between different controversial markets: while kidney sales were generally viewed as ethically unacceptable, commercial surrogacy was viewed as ethically acceptable on average. Across these markets, participants also believed that others would judge the transactions more negatively than they did themselves, suggesting that people systematically underestimate how accepting others are of controversial markets.
Having shown that repugnance depends on the interaction between the severity of the consequences and the vulnerable party's agency, the researchers next asked whether people apply the same moral standards when they are directly involved in the very same transaction rather than observing it from the outside. Using the same experimental setting, they compared the judgments of neutral spectators with those of the two parties involved: the advantaged party making the offer and the vulnerable party deciding whether to accept it. Spectators judged the transactions much like the vulnerable party, whereas the advantaged party was more accepting of them. Giving the vulnerable party a genuine right to refuse reduced opposition across all three groups and largely eliminated these differences.
Taken together, the studies show that repugnance is not an arbitrary gut reaction but follows a clear logic: opposition peaks when consequences are severe and the vulnerable party cannot refuse, and it softens among those in the advantaged position of making the offer. Seen through this lens, the heat of the Spahn debate is unsurprising: how we judge a controversial transaction depends not only on what is traded and under what conditions, but also on where we stand when we judge it. For policy, the studies point to a practical lever: ensuring that vulnerable parties have a genuine ability to say no reduces moral opposition across all sides of a transaction.
This research has recently been published in Games and Economic Behavior and European Economic Review.
