Descartes' Mediations On First Philosophy exemplifies an epistemological shift from the belief in spiritual phenomena to a more secularized approach of reason. Even though Descartes was a devout Catholic, his philosophy focused on the perception of the universe from a mechanical standpoint. Descartes advocated reason over faith in the pursuit of the truth. Much of his philosophy helped lay the foundation of what was to become scientific method. This is evident in what has become known as Cartesian doubt. Following this was his methodology of thorough analysis in order to form a conclusion with absolute certainty. These are what he referred to as clear and distinct truths. One could not arrive at the end of the equation until they had drawn back to a stance of complete doubt. It is through this method of scientific reasoning that we can see the radical shift in thought. God isn't necessarily out of the picture, but what is evident, is a new way in explaining the universe. There was still a great deal of controversy during the period that Descartes wrote the Mediations. Before this Galileo had been jailed for promoting theories that refuted Christian doctrine. Descartes even dedicated the Mediations to those Most Wise and Distinguished Men, the Dean and Doctors of the Faculty of Sacred Theology of Paris. It's as if Descartes was trying to euphemize his philosophy so the religious authority of the time would indirectly accept a philosophical approach that practically refuted their theological belief in regards to how the universe was understood. Descartes approach was that of reason as opposed to spirituality and in his six Mediations, he demonstrates how this philosophy can be applied. As Taylor states in Sources of the Self, "if we destroy this vision of the ontic logos ...