In the following quote, Chatman is talking about how a novel's presentation of detail and description is always intentional and therefore presumed to be meaningful (it asserts detail); a film's presentation of detail and description seems much more incidental (it names detail).
“When I say, “the cart was tiny; it came onto the bridge,” I am asserting that certain property of the part of being small in size and that certain relation of arriving at the bridge. However, when I say “the green cart came onto the bridge,” I am asserting nothing more than its arrival at the bridge; the greenness of the cart is not asserted but slipped in without syntactic fuss. It is only named. Textually, it emerges by the way. Now, most film narratives seem to be of the latter textual order: it requires special effort for films to assert the property or relation. The dominant mode is presentational, not assertive. A film doesn’t say, “This *is* the state of affairs,” it merely shows you that state of affairs.” (Chatman, "What novels can do that films can't, and vice versa," 128)
So many authors write as though they need to simply show a state of affairs, when they are really asserting (arguing for) that state of affairs; authors have lived with their own familiar ideas for so long that they take them as given, when they actually need to be proved. Conversely, authors also often assert things that can simply be presented, particularly when discussing moves in their larger argument that have already been well established by previous research.
A huge part of my task as a substantive editor is to figure out what the author wishes to "assert" and what she merely wishes to "name"—and to subordinate/highlight those accordingly by playing with syntax.