Cold climate predicts the childhood socialization of emotional restraint across pre-industrial societies

<p>Sun (2025) proposed that a cluster of traits common in East Asian populations may be retained Late-Pleistocene Arctic climate adaptations, among them higher emotional restraint, ingroup harmony, perseverance, and cautiousness. The claim rested on analogy with Inuit and polar-worker studies and was never tested against a competing cause or outside East Asia. We recast it as a falsifiable prediction and test it in the Standard Cross-Cultural Sample of 186 pre-industrial societies, using ethnographic childhood-socialization codes with pathogen stress as the rival driver. Colder climate predicts stronger socialization of emotional self-restraint (r = +0.37, n = 137). The effect out-predicts pathogen stress, though the two are collinear (r = −0.67), and it survives controls for cultural non-independence, spatial autocorrelation, measured temperature, an eight-predictor ecological battery, and crop regime. Because the design is cross-sectional, the gradient cannot currently distinguish in-situ cultural adaptation from the arctic-climate retention account Sun proposes, so it corroborates a shared prediction. Of Sun’s eight named traits only three were codeable here; obedience shows a weaker parallel gradient, while work and achievement traits track pathogen rather than cold. A modern cross-national test finds cold-adapted farmer ancestry, which is collinear and entangled (r = 0.92) with Confucian cultural heritage, out-predicting current climate for measures of restraint and patience.</p>