Descartes tells us that he can doubt that "I am in this place, seated by the fire, clothed in a winter dressing gown, that I hold in my hands this piece of paper," because "I perceive so clearly that there exist no certain marks by which the state of waking can ever be distinguished from sleep."

Question

Quizplus · Accepted Answer

Descartes argues that it is possible for him to doubt his current physical state because there are no certain marks that distinguish waking from sleep.

Descartes Tells Us That He Can Doubt That "I Am