The Grapes of Wrath

by John Steinbeck

The causes lie deep and simply—the causes are a hunger in a stomach, multiplied a million times; a hunger in a single soul, hunger for joy and some security, multiplied a million times; muscles and mind aching to grow, to work, to create, multiplied a million times. The last clear definite function of man—muscles aching to work, minds aching to create beyond the single need—this is man.

For man, unlike any other thing organic or inorganic in the universe, grows beyond his work, walks up the stairs of his concepts, emerges ahead of his accomplishments.