Robert Fludd, or Flud, also known as Robertus de Fluctibus, was an English physician, author, and occultist. The son of Sir Thomas Fludd, paymaster to Queen Elizabeth I's forces in France and the Low Countries, Fludd was born at Milgate House, Bearsted, Kent. At the age of seventeen he entered St. John's College, Oxford, then a center of high Anglicanism. After taking his M.A. degree in 1598, Fludd spent some years abroad, studying medicine. On returning to Oxford, he entered Christ Church. He took the degrees of MB and MD in 1605, but had considerable difficulty obtaining from the College of Physicians the right to practice medicine, which was not granted until 1606. It was alleged that he had spoken with contempt of Galen. Nevertheless, he was admitted as a fellow of the College of Physicians in 1609.

As a London doctor Fludd prospered; he was able...