The Enlightenment, a cultural and scientific movement that started in Europe, stressed the idea of reason and rationality over superstition and religion. Enlightenment thinkers dedicated themselves to advancing ideas related to science and government.
Thomas Hobbes, an English philosopher, developed the idea of the social contract—that people exchanged their liberties for the government's protection. John Locke, another English philosopher, further developed the idea of the social contract and stated that people had a right to the protection of life, liberty, and property from their government. If the government did not protect these rights, the people had the right to overthrow the government.
These ideas inspired the American Revolution. When writing the Declaration of Independence, Thomas Jefferson stated that we have the right to "life, liberty, and the pursuit of happiness," echoing Locke's ideas about inalienable rights—or rights that cannot be removed, because humans are born with them. The founding of our country was based on Enlightenment ideas such as the division of the government into three branches, an idea proposed by the Enlightenment philosopher Montesquieu. The idea that we had the rights to life, liberty, and happiness was also enshrined in our Constitution and Bill of Rights, particularly in the idea that the governed have certain rights, such as freedom of speech, that cannot be removed.