A beginner's guide to Voltaire, the philosopher of tolerance and free speech. Voltaire pleads for religious tolerance in the essay while keeping the right to fight vehemently against it and condemn religious extremism of all kinds. This unique combination of arguments makes him one of the most important philosophers in history. In the 18th century, Europe was divided into many competing nation states, many of which had very strong religions backing them with political power. It was dangerous to express an opinion against the church or king because they could have you burned at the stake for heresy or treason. But there were also other ways of thinking about religion and its role in society. Some people believed that human reason was capable of reaching conclusions about God and the universe independent of faith... ... others thought that science would one day reveal all secrets of nature to us through math and experiments. There were also people who argued that religion was necessary for society's stability and good morals. At the time, these ideas were called "philosophy" or "humanism". Voltaire was one of the most famous writers in France and his ideas spread all over Europe. He was not afraid to criticize kings or priests and he wanted to show that everyone has the right to their own opinion so long as they do not hurt others with it.