Self-essentialism underlies social projection to unfamiliar similar others.

Social projection to similar others is a foundational finding in research on social inference. This article offers a novel mechanism for this effect. We propose that people project broad self-knowledge onto social targets with whom they share an isolated cue of similarity through a two-step self-essentialist process: (a) a singular similarity (e.g., shared view on a social issue) is first attributed to a target's self-essence (i.e., the internal, stable, and deeply rooted qualities that make someone who they are, their true and fundamental nature), (b) which then enables the inference that the target and perceiver have similar self-essences, resulting in the projection of other unrelated self-knowledge arising from the perceiver's self-essence. Eight main studies (N = 3,346) and seven supplemental studies (N = 4,472) examine this claim using individual differences, moderation-of-process, and causal experimental designs. Collectively, our studies find that perceivers project self-knowledge perceived as arising from their own self-essence to infer the characteristics of a variety of unfamiliar similar targets (i.e., generically, attitudinally, and politically similar others), to the extent that they attribute the dimension of similarity to the target's self-essence. Although limited to the U.S. cultural context and online convenience samples, our self-essentialist explanation for social projection to similar others offers implications for research on the self and social inference. (PsycInfo Database Record (c) 2026 APA, all rights reserved).