From Mark Irwin's essay, 'Three Notions of Truth in Poetry':

L’éxactitude n’est pas la verité. (Exactness is not truth.)

--Henri Matisse 

If the greatest sources of art –truth, hope, love, joy, despair—are immeasurable, how can the art created from them be exact? I’m reminded of the seemingly various and often sexual, deific origins of art—Etruscan fertility sculptures, cave paintings at Lascaux—and also of a remark by Jasper Johns: Sometimes I see it then paint it, sometimes I paint it then see it. Both are impure situations, and I prefer neither. 

Or perhaps those greater truths reside in the imagination, for they have not completely arrived yet, and like the light of stars, their distance is more alluring. The imagination, or truth partially withheld is what we don’t forget because we must work to retrieve it. Perhaps the German writer Peter Handke summarizes it best: Reason forgets, the imagination never.