From Computational Indeterminacy to the Causal Relevance of Mental Content

A central claim in contemporary cognitive science is that the neural mechanisms that bring about cognitive capacities and behavior are computations. It is also widely assumed that computations are not sensitive to the content, or the semantic properties of representations. From this insensitivity premise, some infer that mental content is causally irrelevant—a position we term the sensitivity argument against the causal relevance of content. This conclusion, however, sits uneasily with everyday situations in which the contents of our representations appear indispensable to our actions. In this paper, we reject the view that such experiences are illusory and instead identify a flaw in the inference from insensitivity to content to its causal irrelevance. Drawing on the phenomenon of computational indeterminacy—the fact that a single physical state can realize multiple formalisms—we argue that content can be causally relevant even when computation itself is content-insensitive. While remaining neutral on the precise link between higher level and physical causation, we show that computational indeterminacy offers a principled route to restoring the causal relevance of mental content.