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
Cogito, ergo sum Translation needs a larger context to determine aspect. Following John Lyons (1982), Vladimir Žegarac notes, "The temptation to use the simple present is said to arise from the lack of progressive forms in Latin and French, and from a misinterpretation of the meaning of "cogito" as habitual or generic." (Cf. gnomic aspect.) Ann Banfield writes (also following Lyons), "In order for the statement on which Descartes's argument depends to represent certain knowledge, … its tense must be a true present—in English, a progressive, … not as 'I think' but as 'I am thinking, in conformity with the general translation of