| Johannes Heurnius | |
| Birth Place: | Utrecht, Seventeen Provinces |
| Death Place: | Leiden, Dutch Republic |
| Doctoral Advisor: | Petrus Ramus Hieronymus Fabricius |
| Doctoral Students: | Otto Heurnius |
| Notable Students: | Nicolaus Mulerius |
Johannes Heurnius (born Jan van Heurne; 4 February 1543 – 11 August 1601) was a Dutch physician and natural philosopher.
Heurnius was born in Utrecht, and studied at Leuven and Paris. He went to the University of Padua to study under Hieronymus Fabricius;[1] and graduated M.D. there in 1566, examined by Petrus Ramus and Fabricius.[2]
He wrote on the Great Comet of 1577; at that time he was town physician in Utrecht. In 1581 he became professor of medicine at the University of Leiden.[3] Heurnius already had a reputation and good contacts with humanist scholars, and was appointed as senior to Gerardus Bontius, an earlier physician on the faculty.[4]
He was a pioneer of the bedside teaching of medicine, and has been given credit for his methods.[5] From Padua he brought not only anatomy in the tradition of Vesalius, but anatomical demonstrations and practical clinical work.[1] It is not clear, however, if the 1591 proposal by Heurnius and Bontius to implement practical teaching on the Paduan lines was accepted officially.[4] The physician Otto Heurnius was his son; Heurnius's ideas on teaching were transmitted widely through Otto, Franciscus Sylvius, Govert Bidloo and Herman Boerhaave.[1] After his father's death, Otto put together his lectures, published in the Opera Omnia, covering medicine both in theory and as a practical discipline.[4] He died in Leiden, Netherlands.
His son, Justus Van Heurn, Van Heurne, or Heurnius (1587 – c. 1653) was a doctor, missionary, translator, and a botanist. He helped prepare one of the earliest translations of the Bible into Malay and was the first European to collect, document, and record many of the South African Cape plants.[6]