Abstract
Thales is considered to be the first philosopher to pose a question about fundamental principles
on which everything else relied. His candidate for ἀρχή was water because he believed that
everything comes from water and that the remaining three elements can also be created from water.
Alchemists, or the first chemists, relied on the ancient tradition, especially Aristotle and the theory
of the four elements. That is how they came to Aristotle’s testimonies about Thales, after which
alchemists, like Helmont, accepted Thales’ idea that water is the basis of everything that exists.
Alchemists were characterized by a tendency to experiment, not only because they tried to turn
other metals into gold but also because they tried to devise medical solutions that would prevent
the appearance of various diseases. Due to their rich experimental experience, alchemists have
been a convenient target for “new philosophers” since the early seventeenth century. Robert Boyle
belonged to that circle because he was a supporter of corpuscular theory. In this paper, I will present
Boyle‘s attempt to replicate alchemical experiments, especially Helmont’s experiment with the willow
tree and Bacon‘s experiment with water. After that, I will show whether Boyle’s interest in the
experimental procedures of alchemists contributed more to the development of modern science
than his mechanistic philosophy.