ABSTRACT
In attempting to cross the historical gaps that shut off the texts of other periods from our own, the reader has often to puzzle over difficult meanings that depend on earlier meanings, even less accessible. These may belong, however, to enabling or constraining semantic types, by reference to which they can be recovered. Genre theory, especially, has much to say about the ways in which types are modified (without being obliterated) in the course of successive literary communications. As experience shows, such modifications can succeed in prompting an appropriate uptake, without their codes ever having been defined, let alone authorized.
