The causes of COVID-19: an uncontrolled experiment in evolution, causation, and public health

The coronavirus disease 2019 (COVID-19) pandemic has intensified debates on causal explanation in biology, particularly regarding the integration of proximate mechanisms with broader ecological, historical, and socio-environmental determinants. Many accounts remain confined to a single explanatory level, limiting their capacity to address the complexity of pandemic emergence and control.

This paper develops a causal account of the COVID-19 pandemic by placing into dialogue Leyes sin causa y causas sin ley en la explicación biológica, by Gustavo Caponi, and Donald Worster's essay 'Another Silent Spring'.

The analysis adopts a conceptual and comparative approach, contrasting Caponi's experimentalist account of causation, centred on intervention and invariance, with Worster's environmental-historical interpretation of pandemic origins. The discussion is further informed by evolutionary medicine and epidemiology.

Caponi's framework clarifies the epistemic role of intervention, while Worster situates the pandemic within a long-term process of ecological transformation driven by human attempts to control natural systems. Together, these perspectives reveal a tension between control as explanation and control as a source of ecological instability.

The COVID-19 pandemic may be interpreted as a paradox of control: human efforts to manipulate biological and ecological processes generate conditions that increase systemic risk. The pandemic thus underscores the need to integrate biological, ecological, and socio-historical dimensions of causation in both explanation and prevention.