First, do no harm does not appear in the Hippocratic Oath. This episode examines what the oath actually says and where it came from: part of the Hippocratic Corpus written between the fifth and third centuries BC, likely not by Hippocrates, surviving in third century AD papyrus fragments and a complete 10th or 11th century manuscript in the Vatican Library. It opens with an oath to Apollo, Asclepius, Hygieia, and Panacea and binds the new physician to treat a teacher like a parent, share money with him, and teach his sons for free. It also protects free and enslaved patients from abuse, demands confidentiality, and forbids cutting, even for bladder stones, leaving that work to specialized craftsmen.

Its rules on lethal drugs and the abortive pessary have been argued over for two thousand years, from Scribonius Largus and Soranus of Ephesus to John M. Riddle and Ludwig Edelstein. The oath survived because it was adaptable. Byzantine Christians replaced the gods and shaped the manuscript like a cross, Thomas Percival published a code of ethics in 1803, and the World Medical Association drafted the Declaration of Geneva in 1948. In 1964 Tufts dean Louis Lasagna wrote a secular version warning against overtreatment and therapeutic nihilism and telling doctors, above all, not to play at God.

• Why a guild might ban poisons to keep physicians from becoming tools of assassination
• Only three of 126 US medical schools still using the original Greek text in 1989, and none by 2018
• Saparmurat Niyazov’s 2005 demand that Turkmenistan’s doctors swear an oath to him
• The 2022 Tamil Nadu controversy over the Charaka Shapath and a dean’s brief dismissal
• A review of 18 modern oaths that found wide variation in what doctors promise