 It might be supposed that the pictorial/discursive distinction is best made in terms of the phenomenal/non-phenomenal distinction, but it is not obvious that this is the case. For one thing, there may be non-phenomenal properties of representations that vary continuously. Moreover, there are ways of understanding pictorial representation that presuppose neither phenomenality nor analogicity. According to Kosslyn (1980, 1982, 1983), a mental representation is “quasi-pictorial” when every part of the representation corresponds to a part of the object represented, and relative distances between parts of the object represented are preserved among the parts of the representation. But distances between parts of a representation can be defined functionally rather than spatially – for example, in terms of the number of discrete computational steps required to combine stored information about them. (Cf. Rey 1981.)