Levels of Explanation Vindicated
Marr’s celebrated contribution to cognitive science (Marr 1982, chap. 1) was the introduction of (at least) three levels of description/explanation. However, most contemporary research has relegated the distinction between levels to a rather dispensable remark. Ignoring such an important contribution comes at a price, or so we shall argue. In the present paper, first we review Marr’s main points and motivations regarding levels of explanation. Second, we examine two cases in which the distinction between levels has been neglected when considering the structure of mental representations: Cummins et al.’s distinction between structural representation and encodings (Cummins in Journal of Philosophy, 93(12):591–614, 1996; Cummins et al. in Journal of Philosophical Research, 30:405–408, 2001) and Fodor’s account of iconic representation (Fodor 2008). These two cases illustrate the kind of problems in which researchers can find themselves if they overlook distinctions between levels and how easily these problems can be solved when levels are carefully examined. The analysis of these cases allows us to conclude that researchers in the cognitive sciences are well advised to avoid risks of confusion by respecting Marr’s old lesson.
KeywordsPerceptual Experience Linguistic Structure Representational Scheme Iconic Representation Nonconceptual Content
We would like to thank Josefa Toribio, Christopher Evans and two anonymous referees for their helpful comments and suggestions on earlier drafts. This research has been partially funded by the MICINN, Spanish government, under the research project FFI2008-06164-C02-02, the CONSOLIDER INGENIO 2010 Program, grant CSD2009-0056, and the Catalan government, via the consolidated research group GRECC, SGR2009-1528.
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