Abstract
Behavioural systems present a relevance problem: there’s too much information about them to include all of it in our explanations, so we must decide what information should be included in and excluded from explanation. One popular solution is to (a) include only information at a single level and (b) exclude information at other levels. This excludes relevant information about interlevel processes. However, neuroscientists have found an implicit way to include relevant interlevel processes in their explanations of behavioural circuits. I argue that we can rationally reconstruct an interlevel theory of relevance for behavioural systems from their explanations of behavioural circuits.