Two spurious varieties of compositionality

The paper examines an alleged distinction claimed to exist by Van Gelder between two different, but equally acceptable ways of accounting for the systematicity of cognitive output (two varieties of compositionality): concatenative compositionality vs. functional compositionality. The second is supposed to provide an explanation alternative to the Language of Thought Hypothesis. I contend that, if the definition of concatenative compositionality is taken in a different way from the official one given by Van Gelder (but one suggested by some of his formulations) then there is indeed a different sort of compositionality; however, the second variety is not an alternative to the language of thought in that case. On the other hand, if the concept of concatenative compositionality is taken in a different way, along the lines of Van Gelder's explicit definition, then there is no reason to think that there is an alternative way of explaining systematicity.This paper has its origin in very helpful and stimulating discussions with Pepa Toribio. I would like to express my gratitude also to Ned Block, Josep Corbí, Joe Lau, Begoña Navarrete, David Pineda, Ignacio Vicario and an anonymous referee for Minds and Machines for valuable comments that led to improvements. A previous version of the paper was presented at the third conference of the European Society for Philosophy and Psychology held in Paris, 1–4 September 1994, where I benefited from comments by G. Rey and J. Higginbotham. Finally, I thank Michael Maudsley for his careful revision of the grammar. Research for this paper has been funded by the Spanish Government's DGICYT, Ministry of Education, as part of the research project PB93-1049-C03-01.