The Uniquely Powerful Impact of Explicit, Blatant Dehumanization on Support for Intergroup Violence

To effectively address intergroup violence, we must accurately diagnose the psychological motives driving it. Dehumanization—the explicit and blatant denial of an outgroup's humanity— is widely considered one such driver, informing both scholarly theory and social policy on intergroup violence. Nonetheless, dehumanization is often intertwined with intense negative affect, raising concerns that dehumanization’s explanatory power is much more restricted than widely assumed. In the extreme, “dehumanization” is merely another way to express intense dislike. If so, then theories of dehumanization distort our understanding of the true motives driving violence. Here, we test dehumanization’s reality and explanatory power through three complementary research streams that employ diverse methods and samples. First, we meta- analyze existing studies on dehumanization and dislike to establish their independent effects on violence (k = 120; N = 128,022). We then test the generalizability of these effects across four violent conflicts in the United States, Russia and Ukraine, Israel and the Palestinian diaspora, and India (NTotal = 3,773). In these studies, we also test whether individuals’ dehumanizing responses are mere metaphor or intended literally. Finally, we isolate dehumanization’s causal impact on violence in another US sample (N = 753). Our results converge to demonstrate that dehumanization is (a) distinct from dislike and often intended literally, (b) a particularly strong predictor of support for violence, and (c) can causally facilitate such support. Collectively, these studies clarify our understanding of the psychology driving violence and can inform efforts to address it.