They do what they are told to do: the influence of instruction on (chess) expert perception-commentary on linhares and brum (2007)

Linhares and Brum (2007) argue that they provide evidence for analogy as the main principle behind experts' acquisition of perceptual knowledge. However, the methodology they used—asking players to pair positions using abstract similarity—raises the possibility that the task reflects more the effect of directional instructions than the principles underlying the acquisition of knowledge. Here we replicate and extend Linhares and Brum's experiment and show that the matching task they used is inadequate for drawing any conclusions about the nature of experts' perception. When expert chess players were instructed to match problems based on similarities at the abstract level (analogy), they produced more abstract pairs than pairs based on concrete similarity. However, the same experts produced more concrete pairs than abstract ones when instructed to match the problems based on concrete similarity. Asking experts to match problems using explicit instructions is not an appropriate way to show the importance of either analogy or similarity in the acquisition of expert knowledge. Experts simply do what they are told to do.