Descartes’ Methodological Doubt

Descartes belonged to the era of Modern Western Philosophy. Therefore, it was quite expected that he would retaliate to the pressuring Medieval philosophers and Ancient philosophers in the Western World. The Ancient and Medieval eras took sense knowledge as their source to develop their philosophy of knowledge. Descartes, the father of rationalism, rejected this method and developed his philosophy using the concept of ideas.

He started by saying that we need to doubt everything. This is because the knowledge of the external world comes from our senses which can at times deceive us. Thus, knowledge from our senses need not necessarily be true. But, if we doubt our sense knowledge than where is the base of our knowledge? “Cogito ergo sum” [I think therefore I exist] is Descartes’ answer. When we doubt the existence of the outside world, our doubting is thinking, which in itself cannot be doubted. Thus, we can be certain of one thing: our thinking proves our existence. This is a self-evident truth. He thus refers to the human mind as the ‘Res Cognitans’ or the ‘The Thinking Brain’ with the mind a s a separate entity from the body.

This methodological doubt is the strongest foundation of Descartes’ Philosophy. He believes that once the mind has moved away from the sense, it will find it easier to recognize as to what is real and what is not. Once he proves his philosophy of knowledge with the help of the methodological doubt, he goes on to prove the existence of the external world by first proving the existence of God.