Notions that lycanthropy was due to a medical condition go back to the seventh century, when the Alexandrian physician Paulus Aegineta attributed lycanthropy to Melancholia or an "excess of black bile".[14] During 1563, a Lutheran physician named Johann Weyer wrote that werewolves suffered from an imbalance in their melancholic humour and exhibited the physical symptoms of paleness, "a dry tongue and a great thirst" as well as sunken, dim and dry eyes.[14] Even King James VI and I in his 1597 treatise Daemonologie does not blame werewolf behaviour on delusions created by the Devil but "an excess of melancholy as the culprit which causes some men to believe that they are wolves and to 'counterfeit' the actions of these animals".[15] The perception of an association between mental illness and animalistic behaviour can be traced throughout the history of folklore from many different countries.[16]