Reijer Hooykaas (1906-1994), a Chemist by training, showed his interest in the history of science with a PhD thesis on the history of the concept of ‘element’ (1933) and additional publications on other topics in the 1930s and 1940s. After the Second World War, he was appointed the first Professor of History of Science in the Netherlands at the Free University of Amsterdam, becoming a key player in the professionalization of this discipline in his country and contributing to the worldwide movement in this direction. His research moved from the history of Chemistry to Crystallography and finally to Geology, publishing a major book on the 19^th century Geology in 1959. About this time he became interested in the history of Portuguese navigations in the 15^th-16^th centuries, with a short article in 1960. In 1962 he visited the University of Coimbra and also lectured at Lisbon and Porto. His contacts with Armando Cortesão and Luís de Albuquerque led to further invitations to give courses on the history of science and attend meetings in Portugal during the 1960s, culminating with an honorary doctorate in Coimbra (1969). Hooykaas learnt Portuguese and retained an interest in Portuguese navigation all his life. He became interested in showing how these navigations made a crucial contribution to the development of modern science. He highlighted the importance of the artisans’ contribution (in this case navigators) to modern science and the relevance of the geographical debates to question the authority of the ancients, a century before of what is usually accepted in connection o the astronomical heliocentric debates of the 17^th century. With his publications in English he made a valuable contribution to popularise this important episode in the history of science at international level, with a final landmark publication in this line in 1987. Hooykaas, an “orthodox Protestant”, was all his life very interested in the science and religion historical relations. He investigated the Merton thesis, which defended the positive impact of Puritanism in the rise of modern science, with particular modifications of his own. Not surprisingly, he became as well interested in the early history of Copernicanism and the science and religion debates that it sparked. One of his lasting contribution was the discovery of the long lost treatise of Rheticus on how to reconcile the Bible and the teaching of his master Copernicus, which Hooykaas published and translated into English in 1984.

29 January 2025, FCUL