  He famously denies that perceptible qualities other than shape and size (and, perhaps, weight) really exist in the atoms themselves: one direct quotation surviving from Democritus claims that ‘by convention sweet and by convention bitter, by convention hot, by convention cold, by convention color; but in reality atoms and void’ (DK 68B9, trans. Taylor 1999a).  As Furley argues, the translation ‘convention’ should not be taken to suggest that there is anything arbitrary about the perception of certain colors, say: the same configuration of atoms may be regularly associated with a given color.  The contrast here is intended to be that between real and unreal properties (Furley 1993; cf. Barnes 1982, pp. 370–7).  What Democritus rejects as ‘merely conventional’ is, perhaps, the imputation of the qualities in question to the atoms, or perhaps even to macroscopic bodies.