Although he wrote a book detailing his theories of the natural world, he delayed its publication following Galileo’s confrontation with the church and instead published The Discourse on Method four years later (Uzgalis 1997). In developing these and other ideas, Descartes eventually wrote several books regarding the nature of existence and knowledge, providing us with plenty of material to study and having a tremendous influence on those who have come after him. Remembered today primarily as the father of modern philosophy, Descartes introduced a shift in thinking from the empiricist school of thought in which people believed all knowledge ultimately comes to us through our senses to the rationalist school of thought in which it was believed that human reason was the source for all human knowledge. “He developed a dualistic system in which he distinguished radically between mind, the essence of which is thinking, and matter, the essence of which is an extension in three dimensions. Descartes’ metaphysical system is intuitionist, derived by reason from innate ideas, but his physics and physiology, based on sensory knowledge, are mechanistic and empiricist” (Watson 2002). To understand how and why Descartes came to be identified as the turning point in modern philosophical thinking, it is necessary to understand how his thinking differed from the philosophers who preceded him as well as how this type of thinking contributed to his fundamental shift from traditional thought.
Descartes was known as a mathematician before he ever became known as a philosopher. Although reports indicate he worked as a soldier in his younger years, “It is not known what his duties were exactly, though Baillet suggests that he would have very likely been drawn to what would now be called the Corps of Engineers. This division would have engaged in applied mathematics, designing a variety of .structures and machines aimed at protecting and assisting soldiers in battle” (Smith 2003). . .