Defining art can be as difficult as describing death.
Here is an explanation of art by Rebecca West in "The Strange Necessity."
"This blazing jewel that I have at the bottom of my pocket, this crystalline concentration of glory, this deep and serene and intense emotion that I feel before the greatest works of art .... It overflows the confines of the mind and becomes an important physical event. The blood leaves the hands, the feet, the limbs, and flows back to the heart, which for the time seems to have become an immensely high temple whose pillars are several sorts of illumination, returning to the numb flesh diluted with some substance swifter and lighter and more electric than itself ... Now what in the world is this emotion? What is the bearing of supremely great works of art on my life which makes me feel so glad?"