We traced the development of sensitivity to symmetric
relational patterns by creating a symmetry match-to-sample
task. Children saw a symmetric standard made up of two
shapes and choose between two novel alternatives: a
symmetric pair and an asymmetric pair. We found that young
children chose randomly between the two alternatives.
Children were not reliably above chance until 8-to 9 years of
age. In a second study, we found that young children could
succeed in making symmetric relational matches if the triads
were designed to invite informative comparisons. These
findings show that relational insight of symmetry develops
relatively late. However, as with other relations, comparison
processes can promote sensitivity to the symmetry relation