I claim that Christiaan Huygens, Isaac Newton and Leonhard Euler belongs in a sarne line of thinking in dynamics. They used Galileo Galilei's theorem on the free fall as a surrogate for dynamics; from there, they were able to formulate more general dynamic categories, blending mechanics and the geometry of infinitesimals in a "geometrical physics". Although H uygens has been studied by historians, I do not believe that due emphasis has been given to the foundations of physics. ln order to analyze the import of his kind of thinking to the establishment of the categories of dynamics, I follow step by step Huygens's calculation of the centrifugal force.
Huyghens; centrifugaI force; Galileo's theorem; virtual processes
