...Poetsput more emphasis on the role of pictures than on the role of propositions. After all, a set of true propositions about z need not constitute an adequate picture of z. The propositions may all be trivial and uninteresting and leave out what is truly interesting or distinctive about z. So poets, on the whole (again, I am generalizing terribly) are more interested in truth as it attaches to pictures, than truth as it attaches to propositions. Thinking about truth in terms of propositions makes us more inclined to believe in the ONE truth since, after all, any proposition must either be true or false, and so there can only be one complete set of true propositions about the world. But thinking in terms of pictures reminds us that any human grasp of this one complete truth is partial, and that in human terms, the idea of multiple distinct but not necessarily incompatible truths may in fact be one that makes a certain sense (emphasis, mine).
Before it forks into knowledge (or perhaps ignorance), belief, which is something generally held to be the case, lives momentarily in a place where a well-informed imagination might come to its aid. So the discussion Jollimore alludes to is not simply an academic exercise. Poets and philosophers have something valuable to contribute to a picture that is permanently missing crucial information.
Seriously, how else could artists portray planets no human eye has seen?