"A picture is not thought out and settled beforehand.  While it is being done it changes as one's thoughts change.  And when it is finished, it still goes on changing, according to the state of mind of whoever is looking at it.  A picture lives a life like a living creature, undergoing the changes imposed on us by our life from day to day.  This is natural enough, as the picture lives only through the one who is looking at it." 

- Pablo Picasso