RESUMO
In 1960, J. Anthony Morris, a molecular biologist at the US National Institutes of Health conducted one of the only non-therapeutic clinical studies of the cancer virus SV40. Morris and his research team aimed to determine whether SV40 was a serious harm to human health, since many scientists at the time suspected that SV40 caused cancer in humans based on evidence from in vivo animal studies and experiments with human tissue. Morris found that SV40 had no significant effect but his claim has remained controversial among scientists and policymakers through the present day--both on scientific and ethical grounds. Why did Morris only conduct one clinical study on the cancer-causing potential of SV40 in healthy humans? We use the case to explain how empirical evidence and ethical imperatives are, paradoxically, often dependent on each other and mutually exclusive in clinical research, which leaves answers to scientific and ethical questions unsettled. This paper serves two goals: first, it documents a unique--and uniquely important--study of clinical research on SV40. Second, it introduces the concept of "the stowaway," which is a special type of contaminant that changes the past in the present moment. In the history of science, stowaways are misfortunes that nonetheless afford research that otherwise would have been impossible specifically by creating new pasts. This case (Morris' study) and concept (the stowaway) bring together history of science and philosophy of history for productive dialog.