Organon §111

Each medicinal substance engenders a certain, unique set of symptoms.

The agreement of my observations of the pure actions of medicines [in provings] with these older reports [of poisonings] written irrespective of curative purposes, and even the accord of these reports [of poisonings] with others of this kind from different writers, easily persuades us that medicinal substances act in their morbid alteration of the healthy human body according to definite, eternal natural laws and, by virtue of these, are able to engender certain, reliable disease symptoms, each substance engendering particular ones, according to its peculiarity.