Art is limitation; the essence of every picture is the frame. If you draw a giraffe, you must draw him with a long neck. If in your bold creative way you hold yourself free to draw a giraffe with a short neck, you will really find that you are not free to draw a giraffe. The moment you step into the world of facts, you step into a world of limits.... This is certainly the case with all artistic creation, which is in some ways the most decisive example of pure will. The artist loves his limitations: they constitute the thing he is doing.
G.K. Chesterton, Orthodoxy