When Mesmerism Came to America
nybooks.com
nybooks.com
The mechanism of mesmerism was disproven by the Ben Franklin committee -- there is no "vital force", akin to a magnetic force, that a mesmerist taps into. Nevertheless, the Franklin committee didn't dispute the effects of mesmerism. As a placebo effect, it is a particularly strong one. Placebo effects often comprise the greater part of accepted medical psychotherapies. While the esoteric/ magical qualities of mesmerism may make rationalists shudder, if it worked well (it did) we might still learn from it.
If the effect is all in my head but it works, then who cares if it's all in my head?