Not just a Magus but also a Mathematicus.
Today is the 482 birthday of one of the most notorious of all Renaissance figures, John Dee. Featured in numerous novels, stage plays, films and television shows he is the epitome of the Renaissance Magus, the astrologer, necromancer, magician, master of dark forces and questioner of angels. This vivid, colourful and powerful image that Dee has projected down the centuries is problematic for the historian of Renaissance mathematics because Dee plays a highly significant role in the development of the mathematical sciences in England in the 16th century and it is often difficult to see the man and not the myth; if you Google his name you get literally thousands of hits for web sites on Enochian magic and conversing with angels. Even such a great historian of science as Owen Gingerich makes the mistake of dismissing Dee as “an eccentric Elizabethan wizard” in his The Book Nobody Read.
Dee was together with Robert Recorde the founder of what is known by historians of mathematics as the English School of Mathematics. This is not a school as a formal institution but rather more a tradition of passed on knowledge and learning. In the middle of the 16th century England lagged far behind the European continent in its levels of mathematical knowledge and education, in fact they were almost non-existent. Recorde and Dee undertook the task of changing this situation. Recorde wrote a series of maths textbooks in English setting out a programme of mathematical education from the elementary, simple arithmetic, to the advanced, astronomy. Over the years Dee wrote and published many new editions of Recorde’s books. In addition Dee, who had travelled widely on the continent and studied under Gemma Frisius at the University of Louvain, brought the newest astronomical instruments as well as the newest terrestrial and celestial globes with him back to England. In his house in Mortlake he possessed what was probably the largest scientific library in Europe, which became a centre of study for those interested in the mathematical sciences and in particular those interested in the new heliocentric theories of Copernicus, Dee owned two copies of De Revolutionibus. His most famous pupil, his foster son Thomas Digges, was the first person to publish a partial translation of Copernicus’ great work. Dee himself corresponded with the leading continental mathematicians such as Tycho Brahe with whom he discussed the mathematical problems of parallax measurement an important theme in the evolution of the new astronomy. Dee also worked for one of the great Elizabethan trading companies The Muscovy Company teaching astral navigation and cartography to the ship’s captains. Dee wrote extensively on mathematical subjects but his most famous mathematical work is his long introductory essay to Billingsley’s first English translation of The Elements of Euclid in which he present an exhaustive survey of the then mathematical sciences and their utility to society.
Next time you stumble across Dee’s name in a novel or film remember he wasn’t just a magus but a real mathematician as well.