The Flemish chemist and physician Jan Baptista van Helmont (1580-1644) attempted to construct a natural philosophical system based on chemical concepts. He also developed the concept of gas.

Jan Baptista van Helmont was born of a noble family in Brussels in January 1580. He studied the classics at the University of Louvain until 1594, but he did not accept a degree because he considered academic honors a mere vanity. He also studied aspects of magic and mystical philosophy in courses given by Jesuit teachers at their recently founded Louvain school, and then he turned to the study of such mystical spiritual writers as Thomas à Kempis. Dissatisfied with all these studies, he turned to medicine. In his new undertaking he was inspired by religious zeal and by the desire to be of service to society.

After obtaining his license to practice, Van Helmont was invited to lecture on surgery at...