The use of the factive verb explain assumes the truth of the following
proposition, in a way that a non-factive such as claim would not. Embedding
propositions in this way can make them more difficult to identify, and more
difficult to challenge. It would therefore be possible to study discussions
between political commentators on radio and politicians or other public
figures. One could study the propositions to which one or both speakers are
committed at a given point in the discourse, whether such propositions have
been asserted or are taken for granted, and which propositions are, conversely,
under explicit questioning in some way. A detailed study of the
syntax and semantics of factive verbs and related linguistic devices is a
necessary prerequisite for such a study. 3
Semantics has not characteristically been applied to practical issues,
although it is clear that there are many problems in, for example, the
interpretation of legal documents, which are essentially semantic. Linguistics
is, however, beginning to provide the tools which would allow such applications
in a principled way, and which would therefore answer this complaint
from Enoch Powell (1980):