ABSTRACT
In the twelfth century, the Andalusian Muslim statesman and philosopher, Abu Bakr Ibn Tufayl, conjectured that all sensory qualities were material, and inferred from this that they would have at least some characteristics that can be discerned independently of sensory experience. This chapter explores how ideas are formed in each modality, and, given how they are formed, what crossmodal correspondences can we expect to find Molyneux’s question has sometimes been thought to be about the “differences between the qualitative or phenomenal character” of visual and tactual experiences of the same thing. The chapter concludes that Molyneux’s question, ostensibly about the crossmodal application of sensory knowledge, is a special instance of the broader set of questions (prompted by Ibn Ṭufayl) about the fungibility of the senses—that is, about how knowledge and general representations/ideas that are normally formed in one way in one modality can be formed in another way in another modality.
