Van Helmont en het gas

Johan Baptista van Helmont (1579-1644) was born in Brussels, around the time the Southern Netherlands ceased their resistance against the Spanish rule. He studied a variety of disciplines in Louvain and made a ‘grand tour’ in Europe, but remained dissatisfied with traditional knowledge, which he regarded as empty phrases and sophistry. His spouse being wealthy, he devoted himself to studying nature anew, unencumbered by prejudice, as Paracelsus (1493-1541) had done before him. Yet in his attempts to explain living and inanimate matter he could not avoid making basic assumptions. Among these was his view that there were only two elements: water and air. Water might carry elementary seeds from which a variety of substances could develop. When a substance was consumed by fire, an ethereal essence would remain, which he called ‘Gas’ (a term perhaps derived from Paracelsian ‘chaos’, perhaps from ‘Geist’). Today ‘gas’ is defined as the volatile state of a given substance, but in Van Helmont’s view it was mainly a metaphysical characteristic. Most of Van Helmont’s work was published only after his death, through a verdict of the Spanish Inquisition.

Conflict of interest: none declared. Financial support: J.P. Gijselhart works part time for the Association of the Dutch Journal of Medicine (Vereniging Nederlands Tijdschrift voor Geneeskunde), Amsterdam.