WITH the onslaught of winter in 1619, a young Frenchman finds himself in Neuberg, a small town in Bavaria. Having completed his formal education, he has joined the army of Duke Maximillian in order to travel and extend his education by observing how practical men handle their affairs. He is becoming disillusioned: this is not leading him to any more certain knowledge than that of the theorizing scholars and philosophers he already knows. With the army's campaign halted until spring, he finds a small, wellheated room and settles down to a long winter's study.
There on the tenth of November, he has a strange but vivid and exhilarating dream. He is on a street swept by a strong wind, almost unable to stand. Suddenly, he hears a clap of thunder and sees a shower of sparks. He is standing in his room and sees a dictionary on the table and
Fishman RS. Descartes' Dream. Arch Ophthalmol. 1971;86(4):446-448. doi:10.1001/archopht.1971.01000010448016