Sixteenth century pharmacology was still very much under the influence of a distinction going back to ancient medicine: the distinction between effects of medicaments that were taken to be explainable by the elementary qualities, their mutual modification in mixture, and the combination of these modified elementary qualities on the one hand, and the effects of medicaments that were taken not to be explicable in this manner.1 Galen coined the expression that a medicament of the latter kind possesses the capacity of (...) acting "by its whole substance,"2 and the question of how actions of the whole substance could be explicated gave rise to heated controversies in early modern pharmacology. Did Galen just... (shrink)