ABSTRACT
Robert Koch started his research in medicine about a decade after the first introduction of the germ theory of disease. Previous to this theory, diseases had been largely explained in terms of miasmas or chemical contagions. After his successful start with anthrax and wound infections, Koch turned his attention to the most dreaded disease of his day, tuberculosis. This chapter outlines Max von Pettenkofer's alternative theory of the causation of cholera, and examines how the dispute between him and Koch was resolved. It presents a version of the postulates closely based on Koch's own writings. The chapter then considers Koch's postulates in the light of the action-related theory of causality. It also examines how Koch did manage to establish the comma bacillus as the cause of cholera, using his observations on the Hamburg cholera epidemic of 1892–3. The action-theory, like any Action, Intervention, Manipulation (AIM) theory of causality, stresses the connection between causal laws and interventions.
