Prichard considered that some early nosologists, namely Sauvages, Sagar and Linnaeus, had distinguished between medical conditions with hallucinations and those involving depraved appetites or feelings. But he credits Pinel as the first in psychiatry to clearly distinguish madness without delerium, in opposition to Locke's widely accepted axiom that insanity always stemmed from faulty intellectual connections or mistaken perceptions. However, Pinel's concept focused on a frenzy of the passions, particularly involving rage and violence. For Prichard the typical syndrome was more a form of extreme eccentricity, and he would later refer to Pinel's type as a madness of the instincts.