   First, they suggest that the signification of T, given a ground model M, is the revision rule τM itself. As noted in the preceding paragraph, we can give a fine-grained analysis of sentences' statuses and interrelations on the basis of notions generated directly and naturally from the revision rule τM. Thus, τM is a good candidate for the signification of T, since it does seem to be “an abstract something that carries all the information about all [of T's] extensional relations” in M. (See Gupta and Belnap's characterization of an expression's signification, given in Section 2, above.) 