The invention of the battery, the electric arc, or X-ray radiation: In the work of Joseph Beuys, references to physical phenomena are omnipresent. It exemplifies the possibility of a connection between art and science in the 20th century. Natural science played a central role for the scientist/artist Joseph Beuys (1921-1986). What method arises from this for his artistic work? The author systematically extracts references to phenomena of classical physics and chemistry, which first appear in Beuys' drawings from the mid-1950s and are later further developed in actions and installations. Through analyses of numerous drawings and energy-specific leitmotifs such as the Eurasian staff or main current, she demonstrates how his energetic view of nature can be traced back to concrete foundations. Beuys' concept of science is situated within the tradition of alternative scientific ideas from Goethe, Rudolf Steiner, or Rudolf Hauschka. His attempt at a synthesis of art and science is significantly influenced by the engagement with the work and thinking of Leonardo da Vinci, who early on became an important figure of identification for Beuys. Therefore, the author discusses in detail the bodies of work: the Giocondology and the drawings related to Leonardo's Madrid Codices.