Patañjali are 196 Indian sutras (aphorisms) on Yoga. It was the most translated ancient Indian text in the medieval era, having been translated into about forty Indian languages and two non-Indian languages: Old Javanese and Arabic. The text fell into obscurity for nearly 700 years from the 12th to 19th century, and made a comeback in late 19th century due to the efforts of Swami Vivekananda and others. It gained prominence again as a comeback classic in the 20th century. Before the 20th century, history indicates the Indian yoga scene was dominated by other Yoga texts such as the Bhagavad Gita, Yoga Vasistha and Yoga Yajnavalkya. Scholars consider the Yoga Sūtras of Patañjali formulations as one of the foundations of classical Yoga philosophy of Hinduism. The ("great commentary") of Patañjali on the of is a major early exposition on Pāṇini, along with the somewhat earlier Varttika by Katyayana. Patanjali relates to how words and meanings are associated – Patanjali claims shabdapramâNaH – that the evidentiary value of words is inherent in them, and not derived externally – the word-meaning association is natural. These issues in the word-meaning relation (symbol) would be elaborated in the Sanskrit linguistic tradition, in debates between the Mimamsa, Nyaya and Buddhist schools over the next fifteen centuries. Sphota Patanjali also defines an early notion of sphota, which would be elaborated considerably by later Sanskrit linguists like Bhartrihari. In Patanjali, a sphoTa (from sphuT, spurt/burst) is the invariant quality of speech. The noisy element (dhvani, audible part) can be long or short, but the sphoTa remains unaffected by individual speaker differences. Thus, a single letter or 'sound' (varNa) such as k, p or a is an abstraction, distinct from variants produced in actual enunciation. This concept has been linked to the modern notion of phoneme, the minimum distinction that defines semantically distinct sounds. Thus a phoneme is an abstraction for a range of sounds. However, in later writings, especially in Bhartrihari (6th century CE), the notion of sphoTa changes to become more of a mental state, preceding the actual utterance, akin to the lemma. Patañjali's writings also elaborate some principles of morphology (prakriyā). In the context of elaborating on Pāṇini's aphorisms, he also discusses Kātyāyana's commentary, which are also aphoristic and sūtra-like; in the later tradition, these were transmitted as embedded in Patañjali's discussion. In general, he defends many positions of Pāṇini which were interpreted somewhat differently