A closer look
In 1721, when smallpox stalked Boston, a single enslaved man changed the course of Western medicine. His name was Onesimus, property of preacher Cotton Mather. Onesimus told his owner about an African practice: rubbing a cut with smallpox pus from a survivor to protect against severe infection. The colony doctors called it witchcraft. Yet Mather tried it—under siege of protests and death threats—and the inoculated group saw deaths drop ninefold. That act whispered the beginning of vaccination decades before Edward Jenner’s famous trials. History remembers Jenner; seldom Onesimus, who imported life-saving immunity knowledge across oceans. The irony: public fear nearly silenced the innovation we now owe our survival to—a pattern that repeats in every medical revolution.
