Because during the Enlightenment, philosophers gave people ideas of self-thought, reasoning, scientific investigation, and self-reliance. This led to the birth of new ideas like the scientific method, new inventions, an increase in knowledge, and, more importantly, an increase in democratic nations. Through the Enlightenment, the people were learning to question authority and think for themselves, sort of a "rules are meant to be challenged" mentality became of this. Many revolutions were started during this time, including the American Revolution. The Enlightenment was an attempt to end the Dark Ages, and bring society into the Light.
