The inherence heuristic across development: systematic differences between children's and adults' explanations for everyday facts.

The inherence heuristic is a basic cognitive process that supplies quick-and-easy answers to what are, in reality, incredibly complex questions about why the broad patterns of the world are as they are (Cimpian & Salomon, 2014-a, 2014-b). This explanatory heuristic satisfies the human need to understand, but it is also a source of bias because the heuristic relies too often on the (easily accessible) inherent features of the entities in the patterns being explained. Here, we investigated the developmental trajectory of this heuristic. Given that the cognitive resources that help override the typical output of the inherence heuristic are scarce in childhood, we hypothesized that the heuristic's output would be more broadly endorsed by children than by adults. Five experiments involving young children and adults (N=480) provided consistent support for this hypothesis. The first three experiments (Part I) investigated participants' explanations for broad patterns (e.g., fire trucks are red) and suggested that, consistent with our predictions, children were particularly likely to endorse inherence-based explanations. The last two experiments (Part II) investigated two intuitions that accompany the output of the inherence heuristic: namely, that the patterns being explained cannot be changed and are temporally stable. As predicted, participants' judgments on these dimensions showed the same developmental differences as the explanations investigated in Part I, with children being particularly likely to see patterns as inalterable and temporally stable. The developmental differences found across these five experiments suggest that children start out with a broad reliance on the explanatory output of the inherence heuristic, a reliance that narrows in scope to some extent as children develop.