For readers unfamiliar with the kāvyaśāstra tradition I present here a brief summary of its concepts and history, including the Vedic origins of kāvya and the important sampradāyas (schools) of kāvyaśāstra, viz., rasa, alaṃkāra, guṇa and dhvani. First of all, though, let’s get some nomenclatures out of the way.
The term kāvyaśāstra refers to the study of kāvya i.e. a literary form that generates beauty and bliss. Actually, nāṭya (drama) is also regarded as a species of kāvya as it is both dṛśya (visual) and śravya (auditory) and it is also the case that kāvyaśāstra is considered to have begun with Bharata Muni’s Nāṭyaśāstra but nāṭyaśāstra as a tradition is generally held to have been separate development from kāvyaśāstra. The Nāṭyaśāstra refers to elements of kāvya such as alaṃkāra, guṇa, etc. only as far as they apply to drama and scholars of kāvyaśāstra such as Bhāmaha tend to advise their readers to refer to the nāṭyaśāstras for knowledge on that subject.
The kāvyaśāstra was initially called kāvyalaṃkāra where alaṃkāra (ornament) was understood in the sense of beauty and thus suggested a study of literary beauty. But later the term śāstra was affixed to give importance to that field of knowledge. According to Acharya Vishweshvara, an important scholar who inter alia has translated and commented on Mammaṭa’s Kāvyaprakasha in Hindi, the term sāhityaśāstra became prevalent to refer to this genre of scholarship after Viśvanātha wrote the famous Sāhityadarpaṇa in the 14th century. However, the word sāhitya itself is traceable to the 7th century literary scholar Bhāmaha who wrote that śabdārthau sahitau kāvyam “kāvya is the union of sound and meaning” i.e. when the beauty and strength of the sound and meaning match each other, kāvya is generated.
The Vedic origins of kāvya
There is no visible evidence of a sāhityaśāstra, i.e. a conscious reflection on what makes kāvya beautiful and blissful, in the Vedas but that does not mean that a sense of it did not exist for it is possible to analyse the poetic qualities of Vedic mantras in a way that meets the standards formally set by the later sāhityaśāstra tradition. Moreover, in the Atharva-veda (10.8.32) itself the Vedas are declared to be the kāvya of the gods without death or old-age (devasya paśya kāvyam na mamāra na jiryati) and the Vedic seers are commonly known as kavis. As an example of a high-quality kāvya in the Vedas consider the famous mantra:
dvā suparṇā sayujā sakhāyā samānaṃ vṛkṣaṃ pariṣasvajāte.
tayor anyaḥ pippalaṃ svādvatti anaśnan nanyo abhicākaśīti.. (Ṛgveda 1.164.20)
Two winged creatures, bound together as friends, have occupied the same tree. One of them eats the fruit while the other, without eating, illuminates (looks on).
This mantra can be interpreted in a variety of ways. Acharya Vishweshvara has suggested that it refers to the three fundamental, beginningless and endless principles of iśvara, jīva and prakṛti – by means of prakṛti, iśvara organises the world in which the jīva, in accordance with its karma, consumes the fruit in the form of pleasure and pain. This mantra manifests the profound philosophical wisdom of the Vedas but one can observe in it also the elements of kāvya. Here iśvara, jīva and prakṛti are not mentioned literally but metaphorically as two birds on a tree. This is an instance of a rupaka-alaṃkāra (metaphor). Both suparṇā sayujā sakhāyā samānaṃ and anaśnan nanyo are examples of anuprāsa (alliteration) which produce a madhurya guṇa (sweet quality). Further, anaśnan nanyo abhicākaśīti “illuminates without eating” involves a vibhāvana-alaṃkāra, which is a case where there is an effect without cause. In the mantra, the splendor denoted by abhicākaśīti is that of sentient life which is possible only through consumption of food. But the animated brightness of iśvara is depicted as possible otherwise. So this is an example of vibhāvana-alaṃkāra. Then, the terms sayujā and sakhāyā are suggestive of eternity (nityatā) and manifests a padadyotya dhvani, according to Acharya Vishweshvara.
Thus, in this mantra we already find evidence of many tropes that became the subject of intense reflection and debate later in the tradition. Acharya Vishweshvara claims that there are hundreds of such mantras to be found in the Vedas. Thus, we can say that even if a full-fledged sāhityaśāstra tradition is not to be found in the Vedas, enough knowledge about the field was available in some form or the other to the rishis. Similarly, while there is no sāhityaśāstra as a vedāṅga (limb of the Veda), works on nirukta (etymology) and vyākaraṇa (grammar) have explored the concept of upamā (simile) as a literary figure with examples drawn from the Vedas. Thus, it would not be unreasonable to conclude that the seed of sāhityaśāstra is to be found in the Vedic tradition wherefrom it germinated, through the conduit of Bharata’s Nāṭyaśāstra, into various literary sampradāyas – rasa, alaṃkāra, rīti-guṇa and dhvani – which differed mainly in the emphasis they put on various elements of kāvya. There is a gap of a few centuries between the Vedic tradition and Bharata, on the one hand, and between Bharata and Bhāmaha, the first known teacher of the alaṃkāra sampradāya, on the other, but the succinct form of their works and references to predecessors suggest that they were exponents of an already well-established tradition.
An outline of history of kāvyaśāstra
Sushil Kumar De, who is considered an authority on the subject of Indian poetics, divides the history of the kāvyaśāstra tradition into four periods:
 Formative Stage: From unknown beginnings to Bhāmaha.
 Creative Stage (650 – 850 CE): From Bhāmaha to Ānandavardhana. It includes the poeticians of the alaṃkāra school (Bhāmaha, Udbhaṭa and Rudraṭa), the rīti school (Daṇḍin and Vāmana), the rasa school (Lollaṭa, Shaṅkuka, Bhaṭṭa Nāyaka) and the dhvani school (Dhvanikāra and Ānandavardhana).
 Definitive Stage (850 – 1050 CE): From Ānandavardhana to Mammaṭa. It includes the poeticians Abhinavagupta, Kuntaka, Rudrabhaṭṭa, Dhanañjaya and Dhanika, Bhoja and Mahimabhaṭṭa.
 Scholastic Stage (1050 – 1800 CE): From Mammaṭa to Jagannātha. It includes mainly Mammaṭa, Ruyyaka and Viśvanāth; later writers on rasa such as Rūpa Goswāmi; writers on kaviśikṣā (poetic training) such as Kṣemendra; and Jagannātha Paṇḍit.
Various kāvya sampradāyas
The rasa sampradāya
According to De, Bharata Muni devotes one chapter in his Nāṭyaśāstra to kāvya in which he discusses alaṃkāras (figures of speech), guṇas (excellence), doṣas (defect) and lakṣaṇas (characteristics) but he has explained them with respect to their capability “of awakening rasa in drama.” It also appears that the rasa doctrine was already in existence prior to Bharata who applied it in the context of drama as a nāṭya-rasa. Subsequently, rasa continued to be associated with dramaturgy in the works of scholars such as Lollaṭa, Shaṅkuka and Bhaṭṭa Nāyaka while the alaṃkāra and guṇa-rīti schools elaborated on the aforementioned elements found in the chapter of poetics and allocated rasa a subsidiary position in their system. It is only with the dhvani school of Ānandavardhana that rasa becomes an essential factor of kāvya in the form of kāvya-rasa. Thus the Nāṭyaśāstra is a seminal text from which diverse sahityaśāstra schools emerged, principal being the rasa sampradāya itself.
I give here in brief the rasa theory as explained by De. A bhāva is a mood which brings forth a sense of the composition – poetry or drama – by means of speech, actions and internal feelings. The sāttvika-bhāvas, eight in number, are the involuntary evidences of the internal feelings. In its permanent state the bhāva is called a sthāyi-bhāva and marks the principal mood of the composition. The āsvāda (relish) of the sthāyi-bhāva by the reader or spectator is rasa. Three elements come together to awaken this sense of relish in the audience and affects rasa: vibhāva, anubhāva and vyabhicāri-bhāva. This is established in the famous formula of the Nāṭyaśāstra: vibhāvanubhāva-vyabhicāri-saṃyogād rasa-niśpattiḥ. A vibhāva is that which makes the permanent mood capable of being sensed, an anubhāva is that which makes it actually sensed, while a vyabhicāri-bhāva is that which strengthens it.
There are eight types of sthāyi-bhāva: rati (love), hasa (mirth), krodha (anger), utsāha (courage), bhaya (fear), jugupsā (aversion), vismaya (wonder) and śoka (sorrow). In case of the sthāyi-bhāva love, examples of vibhāva would be women and the seasons; of anubhāva, glance and embrace; of vyabhicāri-bhāva the transient subordinate feelings of joy or anxiety. Thirty-three such vyabhicāri-bhāvas are enumerated. Corresponding to the eight sthāyi-bhāvas there are eight rasas: śṛṅgāra (erotic), hāsya (comic), raudra (furious), karuṇa (pathetic), vīra (heroic), adbhuta (marvellous), bibhatsa (disgusting) and bhayānaka (terrible).
The alaṃkāra sampradāya
De explains that in the view of the alaṃkāra school, the beauty of kāvya lies in the correct use of figures in the composition of its word (śabda) and meaning (artha). The word and meaning together make the body of kāvya. Although Bhāmaha’s Kāvyālaṃkāra is the earliest extant work dealing comprehensively and specifically with the subject of alaṃkāra-śāstra, various types of alaṃkāras were known to early authors of dramaturgical and grammatical works. Bhāmaha classifies ‘poetic expression into fixed rhetorical categories’ but also attempts ‘to arrive at a synthesis by holding that there may be modes or grades of expression, of which the best mode is that which involves vakrokti [crooked speech]’.
Poetry consists of using language that bears a ‘peculiar charm (vicchitti) or strikingness (vaicitrya)’ and in a manner that is different from the ordinary, matter-of-fact usage. Another principle that is characteristic of alaṃkāra is exaggeration (atiśayokti). The alaṃkāra school does not reject rasa or dhvani but includes it explicitly or implicitly as a type of alaṃkāra. Bhāmaha, Udbhaṭa and Rudraṭa are the main exponents of the alaṃkāra school. Later writers continued to devote a section of their works to the exposition of alaṃkāra but with the rise of rīti and dhvani schools it became evident not only that alaṃkāra did not exhaust kāvya but that it was the least important part of its beauty, concerned as it was merely with external adornment.
The rīti-guṇa sampradāya
Daṇḍin is recognized as the earliest exponent of the rīti school but as with Bhāmaha and the alaṃkāra school, the concept of rīti is much older to him. Further, he is held to stand mid-way between Bhāmaha and Vāmana, who is credited with having developed the rīti doctrine into a proper system. The term rīti or mārga refers to ‘the suitable arrangement of sound and sense for the purpose of producing poetic effect’. Daṇḍin divides speech into ‘a multifarious variety of modes’ and classifies them broadly into two types, vaidarbhi and gauḍī. He gives preference to vaidarbhi rīti ‘which, in his opinion, results from a harmonious unification of the ten guṇas or excellences of composition, the gauḍī being the exactly opposite type’ (ibid). The ten guṇas include: sleśa (well-knit), prasāda (lucidity), samatā (evenness), mādhurya (elegance), sukumāratā (absence of harshness), arthavyakti (explicitness of sense), udāratva (elevation), ojas (force), kānti (agreeableness), and samādhi (transferance). Vāmana classified rītis into three types: vaidarbhi, which unites all the guṇas; gauḍī, which abounds in ojas and kānti; and pāñcālī which is endowed with mādhurya and sukumāratā (ibid, p. 90). He has also recommended vaidarbhi as the best rīti. Subsequently, laṭiya, māgadhi and avantikā rītis were added by later scholars.
The dhvani sampradāya
The seminal works of the dhvani school includes the kārikās (verses) by an anonymous writer, who is usually referred to as Dhvanikāra, the commentary on the dhvani–kārikās called Dhvanyāloka written by Ānandavardhana, and the commentary on the Dhvanyāloka called Locana by Abhinavagupta. The core principle of this school is that the ātman of kāvya is its ‘suggested sense’ termed as vyañjanā, vyaṅgya–artha or dhvani.
In the Indian linguistic traditions, words are related to meaning in three ways. ‘The function by which the primary or intrinsic meaning (mukhya or shakya artha) of a word is known is abhidhā, generally translated by the term Denotation, which gives it its conventional significance (sāṅketita artha). Thus, the concept of the cow is given by the word ‘cow’ by its power of Denotation.
When this abhidheyārtha or the primary meaning of a word is incompatible, another power called lakṣanā or Indication (i.e. transferance of sense) is communicated, whereby another meaning connected therewith is apprehended, either through usage (rudhi) or from some special motive (prayojana). Thus, one can say ‘the country rejoices’ but since the country itself cannot rejoice, it is indicated that the people of the country rejoice.
The vyañjanā or power of suggestion is generally defined as that function of a word or its sense by which a further meaning comes into being when the other functions viz. abhidhā and lakṣanā are exhaushted in their scope, another power is postulated by which a deeper sense, the vyaṅgyārtha, is revealed, consequent upon but distinct from the simple thought. The unexpressed or the suggested sense (vyaṅgyārtha) to which the name dhvani is applied when it is predominant, is posed as the essence of poetry. The best kind [of poetry] specifically called dhvani-kāvya is supposed to be that in which the suggested sense predominates and supersedes the expressed.’
‘The suggested sense, or the unexpressed, has three different aspects: it may either be (1) a matter or an idea (vastu–dhvani), (2) a poetic figure (alaṃkāra-dhvani), or (3) a mood or feeling (rasa-dhvani). The first occurs when a distinct subject or thought (a matter of fact) is suggested; the second, where the suggested sense constitutes something imaginative (not a matter of fact) which, if expressed in so many words, would assume the form of a poetic figure; and the last, where a mood or feeling, which is directly inexpressible but which can be suggested, is the principal element.’