Below is a quote from "The Story of Art by E.H. Gombrich" I read the below text the other day and thought it was interesting. This book was published in 1950. In this chapter he is talking about Dutch art during the 1600's.
If I have called this chapter "The Mirror of Nature", I did not only want to say that Dutch art had learned to reproduce nature as faithfully as a mirror. Neither art nor nature are ever as smooth and cold as a glass. Nature reflected in art always reflects the artist's own mind, his predilections, his enjoyments and therefore his moods.
Without Knowing it themselves, these specialists began to demonstrate that the subject of a painting is much less important than might have been thought. Just as trivial words may provide the text for a beautiful song, so trivial objects objects can make a perfect picture.
A Composer who sets to music not a trivial text but a great poem wants us to understand the poem, so that we may appreciate his musical interpretation. In the same way, a painter painting a scene wants us to understand the scene to appreciate his conception. But just as there is great music without words, so there is great painting without an important subject-matter. It was this discovery towards which the seventeenth century the sheer beauty of the visible world. And the Dutch specialists who spent their lives painting the same kind of subject-matter ended by proving that the subject-matter was of secondary importance.