A Proposal of a Simple Test for Symmetry

Abstract

It is known that most other animals than humans are unable to pass the symmetry test. Some authors of the Cognitive Studies, 15(3), pointed out that the arbitrary matching to sample task, a standard test for the symmetry, includes a time sequence of stimuli, which may cause a difficulty in reversing the relation between the sample stimuli and the comparison stimuli, and in passing the test. Moreover, the task requires ability to actively select a stimulus, which also may cause the difficulty. This paper hence proposes a simple test for symmetry which excludes additional obstacles in the test such as the time order between the stimuli, and also excludes the action of selection.