We tested the hypothesis that political attitudes are influenced by an information‐processing factor – namely, a bias in the content of everyday explanations. Because many societal phenomena are enormously complex, people's understanding of them often relies on heuristic shortcuts. For instance, when generating explanations for such phenomena (e.g., why does this group have low status?), people often rely on facts that they can retrieve easily from memory – facts that are skewed toward inherent or intrinsic features (e.g., this group is unintelligent). We hypothesized that this bias in the content of heuristic explanations leads to a tendency to (1) view socioeconomic stratification as acceptable and (2) prefer current societal arrangements to alternative ones, two hallmarks of conservative ideology. Moreover, since the inherence bias in explanation is present across development, we expected it to shape children's proto‐political judgments as well. Three studies with adults and 4‐ to 8‐year‐old children (N = 784) provided support for these predictions: Not only did individual differences in reliance on inherent explanations uniquely predict endorsement of conservative views (particularly the stratification‐supporting component; Study 1), but manipulations of this explanatory bias also had downstream consequences for political attitudes in both children and adults (Studies 2 and 3). This work contributes to our understanding of the origins of political attitudes. Do political attitudes have their roots in childhood? We hypothesized that an early‐emerging explanatory heuristic influences the formation of proto‐political attitudes, promoting (1) the view that socioeconomic stratification is acceptable and (2) a preference for current societal arrangements over alternative ones. Prior work has suggested that, from a young age, people often explain what they observe heuristically, in terms of easily‐accessible inherent or intrinsic facts (e.g., this group is poor because they're unintelligent). Correlational and experimental evidence across three studies suggested a unique link between reliance on this inherence heuristic in explanation and conservative (stratification‐supporting and, to some extent, tradition‐supporting) attitudes. This work contributes to our understanding of the origins of political attitudes.