 This leads us to consider the philosophical developments in the thought of Bhartṛhari (400 ce), and especially his departures from the conceptions seen in Kātyāyana and Patañjali. Apart from his significant contribution toward an in depth philosophical understanding of issues of the structure and function of language, and issues of phonology, semantics and syntax, Bhartṛhari is well known for his claim that language constitutes the ultimate principle of reality (śabdabrahman). Both the signifier words and the signified entities in the world are perceived to be a transformation (pariṇāma) of the ultimate unified principle of language.