Four treatises which illustrate one of the most original minds of the Renaissance at the height of his powers. Born near Einsiedeln in 1493, Philip Theophrastus von Hohenheim, who later called himself Paracelsus, was the son of a physician. His thirst for knowledge led him to study arts in Vienna, then medicine in Italy, but the instruction left him disillusioned. He had learned to see nature with his own eyes, undiluted by the teachings...