Modelling malaria: Collaboration between Ronald Ross, Karl Pearson, and other mathematicians

Epidemiological modelling has played a pivotal role in simulating disease transmission dynamics and informing public health policy. Tracing its development to the early twentieth century, Ronald Ross’s pioneering contributions have been widely recognized. Recent scholarship has acknowledged Ross’s collaboration with mathematicians; however, his epistemological transition to the model-based style of reasoning remains unaddressed – particularly given that contemporary epidemiological statistics were primarily observational and descriptive rather than analytical. This study reexamines this transition by revisiting the tension between the retrospective accounts in Ross’s autobiography and his rich correspondence with Karl Pearson and other mathematicians. We reveal how cognitive artifacts, abstracted from colonial field observations, were vital to Ross’s adoption of the model-based style of reasoning and the initial success of his collaboration with Pearson. Crucially, without shared cognitive artifacts, Ross’s subsequent collaborations with other mathematicians fractured, prompting him to detach his models from the specific, localized public health interventions that had defined his earlier efforts. By deconstructing how these experiences were later obfuscated through Ross’s self-fashioning, this study sheds light on the origins of today’s data-method complex, highlighting alternative possibilities for the future of epidemiological modelling.