The fundamental premise of the Enlightenment was the application of scientific inquiry and rationality to as many areas as possible of human consciousness.  This meant a radical reconfiguration of human nature and the idea of what people can do.  Instead of locking people into roles that dehumanized or limited human ability, the Enlightenment used rationality and the notion of progress to allow individuals to demand more of themselves and the world around them.  This allowed them to question existing structures of power and government, compelling them to believe that they, too, could have a role in determining their own state of being (both metaphysical and political) in the world.  With this understanding, revolutions began to emerge where a greater sense of empowerment was demanded, and in many cased, achieved.

The Enlightenment was an intellectual movement in Europe in the 1700s.  It stressed a couple of ideas that helped lead to revolutions.

Mainly, the Enlightenment thinkers stressed that people should use their reason to investigate the world.  They said that people were capable of thinking for themselves.  The argued that it did not make sense to just believe in things because tradition or authorities said it was true.  This helped undermine respect for traditional authority such as kings.

The Enlightenment thinkers also stressed that people were inherently equal.  This also helped push people to rebel against monarchies.