Paracelsus (Philippus Aureolus Theophrastus Bombastus von Hohenheim, (1493-1541) was a Swiss physician who also gained magical knowledge from Johannes Trithemius, Agrippa's teacher, and was acquainted with the famous alchemist, Solomon Trimosin (author of Splendor Solis). In his use of herbal remedies and principle of "signatures," he could easily be credited as one of the fathers of modern pharmacology. His work had a major influence on John Dee, Francis Barrett, A.E. Waite, and many others.