Self-reflection focus on the beatific vision after death. The 13th century pope Innocent III wrote about the essential misery of earthly existence in his ""On the misery of the human condition"" – a view that was disputed by, for example, Giannozzo Manetti in his treatise ""On human dignity."" A famous quote of Shakespeare's Hamlet (II, ii, 115-117), expressing the contrast of human physical beauty, intellectual faculty, and ephemeral nature: René Descartes famously and succinctly proposed: "Cogito ergo sum" (French: ""Je pense donc je suis""; English: ""I think, therefore I am""). The Enlightenment was driven by a renewed conviction, that, in the
Cogito, ergo sum of other minds at this point. This is something that has to be thought through by each of us for ourselves, as we follow the course of the meditations. Second, he does not say that his existence is necessary; he says that "if he thinks", then necessarily he exists (see the instantiation principle). Third, this proposition "I am, I exist" is held true not based on a deduction (as mentioned above) or on empirical induction but on the clarity and self-evidence of the proposition. Descartes does not use this first certainty, the "cogito", as a foundation upon which to build