thumb|300px|The [[Temple of Athena Polias (Priene)|Temple of Athena Polias at Priene ]]
Pythius (), also known as Pytheos () or Pythis, was a Greek architect, architecture theorist, and sculptor of the 4th century BC. He designed the Temple of Athena Polias at Priene and the Mausoleum at Halicarnassus, which was regarded in antiquity among the Seven Wonders of the World. It is presumed that he came from the Greek city of Priene. The first-century BC Roman architect Vitruvius called Pythius a "celebrated builder" (de Architectura I.1.12) and referenced lost treatises on architecture written in Greek by Pythius as sources for his Latin architecture manual de Architectura (I.1.15).
Architectural theory
The discipline of architecture
Pythius' Commentaries are lost, but Vitruvius paraphrases his philosophy of architectural education, in which the architect should aim to be a polymath knowledgeable "in all the arts and sciences (De architectura I.1.12)." Pythius was a pioneer because he "propounded the importance of architecture as a learned discipline and sought to establish standards for it." J.J. Pollitt called Pythius' grid-based design "'order' in an extreme degree" and a display of "a kind of icy, intellectual elegance."