Answer: Reason
Explanation: Enlightenment thinkers believed in reason, moreover, in science, education, individualism as a necessity for the attainment of natural rights, which they also believed. Natural rights were the basis of all social arrangements and relations between citizens and government. For the citizens to be aware of their natural rights, they had to be educated, enlightened. Everything that was occurring in society or nature had to be subjected to reason and rational thinking, to study. The Enlightenment thinkers were not atheists, but they did not believe in the supernatural phenomena by which God interacts with the universe. It was considered superstition, instead, God, according to the Enlightenment thinkers, interacts with the universe and humans through the natural rights inherent in all, and that is why everyone is equal.
It is for this reason that God has designated natural rights as a form of interaction with humans, all phenomena are natural, subject to study, scepticism, until they prove something scientifically, not on the basis of faith, or because an absolute has said so. According to the Enlightenment, this is the only way of existence and action, of continuing education and seeking reasons for any occurrence, natural event, or social turmoil and movement, and thus personal enlightenment, therefore reason, is obtained.
