 Proponents of this sort of view think of propositions as structured: as having constituents which include the meanings of the expressions which make up the sentence expressing the relevant proposition. (See, for more discussion, the entry on  structured propositions.)  One important question for views of this sort is: what does it mean for an abstract object, like a proposition, to be structured, and have constituents? But this question would take us too far afield into metaphysics (see  §2.3.3  below for a brief discussion). The fundamental semantic question for proponents of this sort of structured proposition view is: what sorts of things are the constituents of propositions?