""Langue de chien, langue de médecin"" is a French saying meaning ""A dog's tongue is a doctor's tongue"", and a Latin quote that ""Lingua canis dum lingit vulnus curat"" or ""A dog's saliva can heal your wound"" appears in a thirteenth-century manuscript.In Ancient Greece, dogs at the shrine of Aesculapius were trained to lick patients, and snake saliva was also applied to wounds.