GUALTIERO di MORTAGNE. - Medieval philosopher and theologian, master of rhetoric and philosophy at Sainte-Geneviève in Paris from 1126 to 1144, died as bishop of Laon in 1174.
At that time the problem of universals was being debated, and John of Salisbury presents G. as the author of the theory of status, one of the realistic theories that yet unite the universal to the singular. “The followers of G. of M.,” says John of Salisbury, “distinguish various status and say, for example, that Plato, as Plato, is an individual; as a man, is a species; as an animal, a genus...” (Metalogicon, II, cap. 17). G. is also the author of a work *De Sancta Trinitate* and of the 7th treatise (*De coniugio*) of the *Summa sententiarum* by Hugh of Saint-Victor.
**GUALTIERO** (WALTER) di REINAU: See WALTER DI REINAU.