synaesthesia a conscious experience in which qualities normally associated with one sensory modality are or seem to be sensed in another. Examples include auditory and tactile visions such as ‘loud sunlight’ and ‘soft moonlight’ as well as visual bodily sensations such as ‘dark thoughts’ and ‘bright smiles.’ Two features of synaesthesia are of philosophic interest. First, the experience may be used to judge the appropriateness of sensory metaphors and similes, such as Baudelaire’s ‘sweet as oboes.’ The metaphor is appropriate just when oboes sound sweet. Second, synaesthesia challenges the manner in which common sense distinguishes among the external senses. It is commonly acknowledged that taste, e.g., is not only unlike hearing, smell, or any other sense, but differs from them because taste involves gustatory rather than auditory experiences. In synaesthesia, however, one might taste sounds (sweet-sounding oboes). G.A.G.