>This harm-avoidant bias after citalopram was also evident in behavior during the ultimatum game, in which subjects decide to accept or reject fair or unfair monetary offers from another player. Rejecting unfair offers enforces a fairness norm but also harms the other player financially. Enhancing serotonin made subjects less likely to reject unfair offers. So essentially a subject with enhanced serotonin was more li…
It's saying that serotonin doesn't make you a better person or more fair in an objective sense, it just strengthens your feelings of empathy, which makes you a better person whenever the good and your feelings about it are by chance aligned.