 Thus, he imagined a character (later on called “Hero” by Evans 1980) who has only non-spatial auditory experiences. Hero perceives sounds, but he does not perceive them to be located in physical space. What Strawson tried to show is that Hero needs an “analogue” to the notion of space in order to “locate” sounds when they are not actually heard. This analogue is provided by what Strawson calls a “master-sound”, namely a constant sound varying in pitch. Any particular sound is heard against the background of the master-sound. Thanks to the master-sound, Hero can distinguish between experiencing the same particular sound again (when its “location” as provided by the master-sound is the same), and experiencing successively two particular sounds of the same type (when they have different “locations” on the master-sound map). Evans (1980) questioned the claim that the master-sound could play the role of physical space in grounding the notion of objective particulars; see also Strawson’s (1980) reply to Evans.