Descartes asks the following: "how do I know that I am not also deceived each time I add together two and three"? Furthermore, "If, however, it were repugnant to the goodness of God to have created me subject to constant deception, it would seem likewise to be contrary to his goodness to allow me to be occasionally deceived; and yet it is clear that this is permitted." From this Descartes concludes that …
A) "God does not exist."
B) "religious authority is not trustworthy."
C) "the results of mathematics, such as 2 + 3 = 5 cannot be doubted."
D) "there is nothing of all that I formerly believed to be true of which it is impossible to doubt."

Question

Quizplus · Accepted Answer

Descartes concludes that because he cannot be absolutely certain that he is not being deceived, there is nothing he formerly believed to be true that he cannot doubt. This results in his famous statement "Cogito, ergo sum" or "I think, therefore I am," which serves as the foundation for his philosophy of skepticism and the search for certain knowledge. Therefore, choices A, B, and C are all incorrect.

Descartes Asks the Following: "How Do I Know That I