In Marlowe's Doctor Faustus, morality is tied to the concept of sin, which is defined by Christianity as actions that go against God's will. By entering a pact with Lucifer, Faustus commits a serious sin, as he not only disobeys God but also willingly chooses to forsake obedience, opting instead to align himself with the devil.
Conversely, Descartes in his "Discourse on Method" does not aim to teach about sin and its implications. He instead focuses on how individuals can discern truth through science and independent thought, apart from the limitations of their senses. He believes in God's existence because he can reason that a perfect mind must exist since he recognizes his own imperfection.
Marlowe’s narrative revolves around Faustus's flaws and God's judgment on him, while Descartes simply acknowledges God's existence through his recognition of imperfection. His reasoning follows: "If I am imperfect and can conceive of perfection, then a perfect God must exist."