The theory of Indian classical music did not emerge fully formed from a single moment of inspiration. It was built across two thousand years of continuous argument: three foundational texts marking the major stages of that argument, each one transforming the tradition it inherited.
Natya Shastra
The Natya Shastra (the "Treatise on Drama") is the foundational text of Indian aesthetics. Its 6,000 verses cover not only music but theatre, dance, poetry, costume, makeup, the construction of performance spaces, and the psychology of the audience. It is among the most comprehensive works on the performing arts in world literature.
Bharata's contribution to music theory centres on two concepts that would shape everything that followed: the grama (the base scale system, from which all melody was derived) and the jati (melodic types that are the ancestors of the modern raga). The Natya Shastra does not use the word "raga" (that comes later), but its jati system establishes the principle that would become raga: a melodic framework defined not just by its notes, but by its emotional character, its characteristic phrases, and its rules of usage.
The Natya Shastra is also where rasa theory originates. Bharata identifies eight fundamental emotional essences (rasas) and explains the mechanism by which art evokes them : a theory that would be elaborated by Abhinavagupta five centuries later and remains the cornerstone of Indian aesthetic philosophy to this day.
The text presents itself as the direct teaching of Brahma, the creator god, who devised the Natyaveda (the fifth Veda of performance arts) to provide all people: not just those of high caste who could study the four traditional Vedas, access to sacred knowledge. Whether historically accurate or not, this framing reflects the profound seriousness with which classical music was regarded in India: not as entertainment, but as a spiritual practice.
Brihaddeshi
The Brihaddeshi ("The Great [Work] on Regional [Music]") is where the word "raga" first appears in its technical sense. Matanga defines it explicitly: a raga is a tonal framework that "colours the mind" through a specific arrangement of notes with specific emotional intent.
This is a historical watershed. Before Matanga, Indian music theory described melodic types in terms of scale degrees and modal formulas. After Matanga, the raga (as a living entity with personality, emotion, and identity) becomes the central concept of the entire tradition.
Matanga's text is also significant for its treatment of the distinction betweenmarga (classical, pan-Indian) and desi(regional, folk) music. He is the first theorist to take desi music seriously: to argue that regional melodic material has value and can be absorbed into classical practice. This democratic impulse in a ninth-century text is striking, and it set a precedent for the ongoing absorption of folk material that has kept the classical tradition alive across centuries.
The Brihaddeshi also contains the first systematic catalogue of ragas, naming and describing dozens of melodic frameworks that would be refined in the centuries to follow. Many names in that list are still recognisable in the modern tradition: a remarkable continuity across eleven centuries.
Sangita Ratnakara
The Sangita Ratnakara (the "Ocean of Music") is the most comprehensive musicological treatise ever written in the Sanskrit tradition. Its seven chapters cover pitch theory, scale systems, the classification of ragas, rhythm and tala, instruments, dance, and performance practice. It synthesises everything that preceded it and adds systematic original scholarship on almost every topic.
Sarngadeva was a Kashmiri Brahmin who served as minister at the court of the Yadava king Singhana in Devagiri (present-day Daulatabad). He wrote at a moment of historical inflection: the pre-Islamic period of Indian music was reaching its classical peak, while the first major Persian-influenced transformations were imminent. The Sangita Ratnakara captures the tradition at this moment in extraordinary detail.
The text's treatment of ragas is particularly significant. Sarngadeva lists 264 ragas with their grammatical rules, their emotional characters, their associated times, and their characteristic phrases : a systematisation that gave subsequent generations a map of the entire territory. His formal definition of raga: "that which colours the mind and delights the hearts of people", remains the standard definition quoted today.
The Sangita Ratnakara is also where the theory of the ten parent scale systems, later adapted by Bhatkhande as the ten thaats of Hindustani music, has its origins. Sarngadeva's system of mela and janya (parent and derivative) ragas was the ancestor of both the Hindustani thaat system and the Carnatic melakarta system. The two major living traditions of Indian classical music both trace their theoretical foundations through this text.
After the Three Texts
The tradition did not stop with Sarngadeva. The fourteenth century broughtSangita Sudha and Sangita Darpana; the sixteenth century brought Pundarika Vittala's attempts to reconcile Hindustani practice with Sanskrit theory. The eighteenth century brought Svaramela Kalanidhiby Ramamatya, which systematised the Carnatic mela system.
But the twentieth century's most important contribution came not from a Sanskrit scholar but from a lawyer-turned-musicologist: Pandit Vishnu Narayan Bhatkhande (1860–1936). His system of ten thaats, grouping all Hindustani ragas under ten parent scales: the framework taught in every Indian music conservatory today. His notation system made written transmission possible for the first time. And his collection of compositions from across the gharana traditions, published in six volumes as Hindustani Sangit Padhdhati, preserved material that might otherwise have been lost when the oral tradition was disrupted by the twentieth century's upheavals.
Bhatkhande worked alongside Pandit Vishnu Digambar Paluskar, who opened the first public music schools in India: making classical music education available beyond the closed household of the gharana for the first time. Their combined work transformed the tradition from an esoteric lineage-based knowledge system into a teachable curriculum. Whether that transformation preserved more than it lost is a question Indian musicians are still debating.