  Du Châtelet herself spent time running extensive experiments to gain understanding of various natural phenomena. She set up a lab at her estate Cirey in which she and Voltaire both undertook experiments (e.g. Walters 1967). Her descriptions of experiments undertaken to determine the nature and propagation of fire in her Dissertation on the Nature and Propagation of Fire attest to this fact. She was also well educated on scientific advancements of her day, most especially in astronomy and physics. Her comments in the Foundations on scientific methodology focus primarily on her analysis of the method of great astronomers and physicists. Here, we focus on her explicit theorizing on the role of hypotheses in science, for her views on this topic place her clearly at the start of the hypothetico-deductive tradition in scientific methodology.