Why is the Enlightenment a Significant Event? It was an intellectual movement in thinking, which moved society's thinking away from religious thinking, dominated by the Church, to rational thought dominated by science The Enlightenment (or 'Age of Reason') is a term used to describe the philosophical, scientific, and rational attitudes, the freedom from superstition, and the belief in religious tolerance of much of 18th-century Europe. People believe the start of the Enlightenment period was between 16th and 19th century. However, cultural historians date the beginning of the enlightenment to the work of Newton,