Age of Enlightenment Louis XV until the French Revolution. If taken back to the mid-17th century, the Enlightenment would trace its origins to Descartes' "Discourse on the Method", published in 1637. In France, many cited the publication of Isaac Newton's "Principia Mathematica" in 1687. It is argued by several historians and philosophers that the beginning of the Enlightenment is when Descartes shifted the epistemological basis from external authority to internal certainty by his "cogito ergo sum" published in 1637. As to its end, most scholars use the last years of the century, often choosing the French Revolution of 1789 or the beginning of
Mr. Cogito human personality. The third, "Pan Cogito a perła" ("Mr. Cogito And A Pearl") – an unrhymed narrative of a pearl stuck in Mr. Cogito's shoe, treated as a metaphor of having to face life's adversities. The next poems – "Pan Cogito myśli o powrocie do rodzinnego miasta" ("Mr. Cogito Considers Returning to His Native Town"), "Pan Cogito rozmyśla o cierpieniu" ("Mr. Cogito Meditates on Suffering") and "Przepaść Pana Cogito" ("The Abyss of Mr. Cogito") depict Mr. Cogito confronting various existential dilemmas. Existential problems are a presence throughout the collection, appearing in the following texts: "Pan Cogito a myśl czysta" ("Mr.