Fig. 1: showing overview and design of studies and the intervention Unlimited

a In Study 1, Black and white American participants were randomly assigned to one of five conditions. Each group was exposed to one intervention or control. Participants then read a vignette about either a Black or a white man suffering from poverty. Participants’ and target’s ethnicities were mismatched to create an intergroup context. Participants answered the empathic reactions and drivers’ questions and decided if they wanted to donate from a bonus payment to help individuals in a situation similar to the vignette. Study 2 was identical to Study 1, but participants’ and target’s ethnicity were matched, creating an ingroup context. Study 3 assigned American participants into one of five groups as above. After completing the intervention, participants read four randomly presented testimonies from Syrian refugees who had fled to the US. Participants answered empathic reaction questions after each testimony (four ratings in total), and empathic driver questions after the last testimony. They were then given the opportunity to donate from a bonus payment to help people in similar circumstances as the targets in the testimonies. Study 4 was identical to Study 3, but with less engaging testimonies, and with changes to two of the interventions: Malleable was transformed into a combination of the previous Malleable and Normative interventions and a new Normative intervention was created. In Study 5, we replicated interventions used in Hasson and colleagues’ Study 3 (Unlimited, Limited and Hasson Control), as well as the control from Studies 1–4. We used a within-subjects design on Democrat or Republican voters in the latest US presidential election and participants reported single-item empathy, empathic reactions, as well as support for social actions for both in- and out-group members. b Screenshot of the intervention Unlimited (studies 1-4), also used by Hasson and colleagues¹⁸.