Before revision: History upKosmos 1upCasio BiolatorJapanese Biomate biorhythm calculator The 23- and 28-day rhythms used by biorhythmists were first devised in the late 19th century by Wilhelm Fliess, a Berlin physician and friend of Sigmund Freud.
After revision: History The 23- and 28-day rhythms used by biorhythmists were first devised in the late 19th century by Wilhelm Fliess, a Berlin physician and friend of Sigmund Freud.