Two Commissions, One Dissent, and What Was Thrown Away with the Fluid

Two bodies reported in 1784. The one chaired by Benjamin Franklin drew on the Academy of Sciences and the Faculty of Medicine and included Antoine Lavoisier and Joseph-Ignace Guillotin, with the astronomer Jean-Sylvain Bailly writing the report. A second, from the Royal Society of Medicine, worked separately and reached a similar verdict, with one member declining to sign: the botanist Antoine Laurent de Jussieu argued that the commissioners had disproved the fluid without accounting for the effects, and that something in the interaction between operator and patient still required explanation. He was right about the gap, and it took sixty years for anyone to take it up properly.

The commissions had established that imagination could produce convulsions, insensibility and relief, and then filed that under refutation rather than under discovery. James Braid picked the observation back up in the 1840s, renamed the state hypnotism, and located it in the subject rather than the operator, which is the line that runs into modern clinical practice. The 1784 reports are therefore both the founding document of controlled testing and a case study in how a negative finding can discard a positive one.