Did Keynes Have Syphilis?

Drawing on previously unpublished archival material, this paper considers the hypothesis that John Maynard Keynes had syphilis. Applying the classical framework for retrospective syphilis diagnosis, the paper examines his sexual history, evolving symptoms, and medical treatments. Most notably, the mix of toxic substances he received in the years before his death was the standard Combined Treatment for syphilis. This investigation raises substantial doubts about bacterial endocarditis and proposes cardiovascular syphilis as the most plausible alternative. Beyond his heart condition, the paper contributes to a broader understanding of Keynes’s health.