Energy/history

Famous quotes containing the words energy and/or history:

“The persons who constitute the natural aristocracy, are not found in the actual aristocracy, or, only on its edge; as the chemical energy of the spectrum is found to be greatest just outside of the spectrum.”
—Ralph Waldo Emerson (1803–1882)

“The history of all hitherto existing society is the history of class struggles.”
—Karl Marx (1818–1883)