Voltaire - French Enlightenment philosopher who believed in freedom of religion and believed in the idea the church and State should be separate.
Baron de Montesquieu - French political philosopher and writer who believed that the powers of the government should be separated into different branches so that they could check and balance each other out.
Thomas Hobbes - An English philosopher who saw the need for some form of ordered government to prevent a state of constant war with everyone against everyone else. He favored an absolute monarch as the preferred form of government.