Natural intensions

There is an attractive way to explain representation in terms of adaptivity: roughly, an item R represents a state of affairs S if it has the proper function of co-occurring with S (that is, if the ancestors of R co-occurred with S and this co-occurrence explains why R was selected for, and thus why R exists now). Although this may be an adequate account of the extension or reference of R, what such explanations often neglect is an account of the intension or sense of R: how S is represented by R. No doubt such an account, if correct, would be complex, involving such things as the proper functions of the mechanisms that use R, the mechanisms by which R fulfills its function, and more. But it seems likely that an important step toward such an account would be the identification of the norms that govern this process. The norms of validity and Bayes' Theorem can guide investigations into the actual inferences and probabilistic reasoning that organisms perform. Is there a norm that can do the same for intension-fixing? I argue that before this can be resolved, some problems with the biosemantic account of extension must be resolved. I attempt to do so by offering a complexity-based account of the natural extension of a representation R: for a given set of ancestral co-occurrences Z, the natural extension is the extension of the least complex intension that best covers Z. Minimal description length is considered as a means for measuring complexity. Some advantages of and problems with the account are identified.