Abstract: lthough even very young children were indicated capable of simple inductive reasoning, the basis underlying the early induction remains hotly debated. Thematic relations play an important role in children’s cognitive development. Because thematic association was a salient response during categorization and analogical reasoning tasks in young children, we hypothesized that thematic relations, which were external relations among objects co-occurred in space and time, can support children’s inductive reasoning when the inferred property was situational.
Using classical picture-triad induction tasks, this study explored the roles of thematic relations in children’s inductive reasoning when thematic relations were pitted against perceptual similarity (experiment 1) or taxonomic relations (experiment 2). The inductive tasks included two kinds of property inferences: internal property inferences and situational property inferences. The participants were 4-5 years olds. Each child completed either internal property inferences or situational property inferences.
The result of experiment 1 demonstrated: when thematic relations competed with perceptual similarity, children from 4.5 years made thematic relation-based induction in situational property inference, whereas there was no significant difference between similarity-based induction and thematic relation-based induction in 4-5 years olds’ internal property inference. The result of experiment 2 showed: when thematic relations competed with taxonomic relations, children from 4.5 years made situational property inference based on thematic relations, whereas those from 5 years made internal property inference based on taxonomic relations. Both experiments showed that children from 5 years olds can selectively use different relations to make inductive inferences of different properties.
The major finding of the study was that thematic relations can support children’s inductive reasoning. Thematic relations play a primary role in young children’s inductive inference of situational property. In contrast, , thematic relations, like perceptual similarity, are less important while taxonomic relations served the chief basis during inductive inferences of internal property.

Key words: thematic relation, perceptual similarity, taxonomic relation, inductive reasoning, property effect