Pratyabhijñā or Pratyabhigyā (pratyabhijñā) is an idealistic, monistic, and theistic school of philosophy in Kashmir Shaivism which originated in the ninth century CE. The term Trika was used by Abhinavagupta to represent the whole of Kashmir Shaivism, or to designate the Pratyabhijñā system. The name of the system is derived from its most famous work, Īśvara-pratyabhijñā-kārikā by Utpaladeva. Etymologically, pratyabhijñā is formed from prati- ("re-") + abhi- ("closely") + *jñā ("to know"), so the meaning is "direct knowledge of one's self," "recognition." The central thesis of this philosophy is that everything is absolute consciousness, termed Śiva, and it is possible to "re-cognise" this fundamental reality and be freed from limitations, identified with Śiva and immersed in bliss. Thus, the slave (paśu: the human condition) shakes off the fetters (pāśa) and becomes the master (pati: the divine condition). The Pratyabhijñā system had a period of intense development between the ninth and the eleventh centuries, with a lineage of masters and disciples who wrote treatises and mystical poetry. The founder of the Pratyabhijñā school was Somananda (875–925 CE); his work Śivadṛṣṭi is the basis of the system. He was followed by his son and disciple Utpaladeva (900–950 CE) who wrote the most important treatise of the system, Īśvara-pratyabhijñā-kārikā, a philosophical treatise discussing the fundamental doctrine of the school and comparing it with various rival schools, analysing the differences and refuting them in the style of Buddhist logic. The name of the school is derived from the title of this work; in the rest of India, the whole Kashmiri Shaivite philosophy was sometimes referred to by the name Pratyabhijñā Śāstra. Another important master of this school is Abhinavagupta, who carried out a synthesis between various schools of Kashmir Shaivism in his magnum opus, Tantrāloka; Abhinavagupta also wrote two commentaries on Īśvara-pratyabhijñā-kārikā.