In the Meditations, Descartes first utilizes the faults of the senses to sow doubt; he contends that since the senses can occasionally be deceptive, we have no reason to put our faith in them.
He experiences his body through the senses, although these have been shown to be untrustworthy in the past. Descartes comes to the conclusion that his existence as a thinking being is the only unquestionable knowledge. As the sole quality about him that cannot be questioned, thinking, it is what makes him who he is.
Descartes initially believes that everything he observes is false and untrue.
Descartes' wicked demon serves as the focal point of a thought experiment designed to determine whether there is an undeniable truth. He assumes that no God exists and that there is instead an evil demon who lies to us about everything in this thought experiment.
Descartes asserts that he is, and he knows this to be true. Descartes comes to the conclusion that he is a living creature. Descartes believes that the adage "I am, therefore I exist" is unavoidably accurate. According to Hume, exterior objects are similar to our mental perceptions.
Dreaming. Descartes asserts that he might just be dreaming for all he knows.
Descartes was disappointed when he realized that many of the purported truths he had learnt in his boyhood were erroneous.
