"Art is an institution to which we turn when we want to feel a shock of surprise. We feel this want because we sense that it is good for us once in a while to receive a healthy jolt. Otherwise we would so easily get stuck in a rut and could no longer adapt to the new demands that life is apt to make on us. The biological function of art, in other words, is that of a rehearsal, a training in mental gymnastics which increases our tolerance of the unexpected." - Ernst Gombrich