Infants' ability to draw inferences about nonobvious object properties: evidence from exploratory play

Generalizing knowledge about nonobvious object properties often involves inductive inference. For example, having discovered that a particular object can float, we may infer that other objects of similar appearance likewise float. In this research, exploratory play served as a window on early inductive capability. In the first study, 48 infants between 9 and 16 months explored pairs of novel toys in 2 test conditions: violated expectation (two similar toys were presented in sequence, the first toy produced an interesting nonobvious property, such as a distinctive sound or movement, while the second toy was invisibly altered such that it failed to produce the nonobvious property available in the first toy), and interest control (two similar-looking toys were presented in sequence, neither of which produced the interesting property). Infants quickly and persistently attempted to reproduce the interesting property when exploring the second toy of the violated expectation condition relative to the first toy of the interest control condition (a baseline estimate) or the second toy of the interest control condition (an estimate of simple disinterest). The second study, with 40 9-16-months-olds, confirmed these results and also indicated a degree of discrimination on infants' part: Infants seldom expected toys of radically different appearance to possess the same nonobvious property. The findings indicate that infants as young as 9 months can draw simple inferences about nonobvious object properties after only brief experience with just 1 exemplar.