Mikkyà  (, from ), or Japanese Esoteric Buddhism, is the lineage of Vajrayana Buddhism transmitted to Japan, primarily in the early Heian by Kà «kai, and to a later extent by Saichà  and his successors such as Ennin. It consists of complex systems of icons, meditative rituals, and ritual languages; distinct from the exoteric (, é¡ÂçµÂ) schools.
Mikkyà  is descended most recently from Tangmi, especially the dual mandala system taught by Huiguo, itself derived from Indo-Chinese tantric masters such as Amoghavajra. Shingon focuses almost exclusively on esotericism, while Tendai views exoteric and esoteric doctrines as complementary. Shugendà  is a syncretic tradition which integrates mikkyà  with Shintà  and Taoist practices. Esoteric practices are diffused throughout the Japanese Buddhist tradition in various forms outside of these schools.
Mikkyà  has been influential in Japanese culture and history, shifting aristocratic court culture away from the Confucian ritsuryà  political structure, and contributing to the development of Japanese literature through waka and the development of the kana syllabary.
In older Chinese literature, the term esoteric is used rhetorically to "designate what this or that writer feels is superior or best in the tradition." Aaron Proffitt argues that "'Esoteric Buddhism' can be taken as a synonym for Mahayana Buddhism itself" in particular contexts, where it takes a polemical rather than descriptive function. The "esoteric" appellation was applied Mahayana to distinguish it from other vehicles as early as the 5th century. The Dàzhìdù lùn (Treatise on the Great Perfection of Wisdom) distinguishes between esoteric (mimi, ç¥Âå¯Â) and exoteric (xianshi, 顯示) Buddhadharma:
<blockquote> In the exoteric [form], the Buddha, , and are all fields of merit since their defilements have been exhausted without residue. In the esoteric [form], it is explained that bodhisattvas attain the acquiescence to the nonproduction of the dharmas... </blockquote>
In the 9th century Kà «kai introduced his own esoteric-exoteric taxonomy, theorizing the esoteric as always-already present in the exoteric teachings, while simultaneously the consummation and highest form of those teachings. He similarly presents Shingon as "vajrayana of secrecy", separate from both the Mahayana and Hinayana teachings. Kà «kai used a number of other terms for his lineage, such as the "mantra treasury" and , literally "vajra vehicle". Taimitsu (å°å¯Â) and Tà Âmitsu refer to the esoteric lineages of Tendai and Shingon respectively. Historically, shingon was largely interchangeable with mikkyà Â; sources often refer to Tendai esotericism as "the shingon of the Tendai lineages."
Elements such as mantra, dharani, and various esoteric texts were already present in Japan before Kà «kai. Dà Âshà Â, Dà Âji, Simsang, Kaimei, and other clerics introduced esoteric sutras to Japan before the Heian era. à Âya Tokujà  used the term nanmitsu (Ã¥ÂÂå¯Â) to refer to this Nara-period esotericism.In the 17th century, sectarian scholars began distinguishing between zomitsu and junmitsu, or "miscellaneous esotericism" and "pure esotericism" respectively, to describe the disparate, diffused esoteric elements versus the highly-structured approach of the Shingon and Tendai schools. This distinction was introduced by the Tokugawa priest Ekà  (1666-1734). Ryà «ichi Abe is critical of this taxonomy, noting that Kà «kai himself imported various zomitsu scriptures, while the junmistu VairocanÃÂbhisaá¹Âbodhi Sà «tra, understood as the primary source of Kà «kai's school, was already circulating in Japan before Kà «kai's first travels to China.
Scholarly approaches to mikkyà  often stress the attainment of Buddhahood "in this very body" (sokushin jà Âbutsu, å³身æÂÂä½Â), or within one's lifetime. This is achieved through the practice of the "Three Mysteries" (sanmi, ä¸Âå¯Â) of mudra, mantra, and mandala. These correspond to body, speech, and mind respectively. The Three Mysteries "awaken beings to the true nature of reality" which is constituted by the identity of all things with MahÃÂvairocana. This is a "process of mutual interpenetration" referred to as nyà « ga gan yà « (å ¥æÂÂæÂÂå ¥, "entering me, me entering").
Kà «kai introduced the integrated practice of the "Womb realm mandala" (Sanskrit: MahÃÂkaruá¹ÂÃÂ-garbhodbhava-maá¹Âá¸Âala, èÂÂèÂÂçÂÂæÂ¼è¼羠) and the "Vajra realm mandala" (Sanskrit: VajradhÃÂtu-maá¹Âá¸Âala, éÂÂÃ¥ÂÂçÂÂæÂ¼è¼羠) to Japan from Huiguo. These mandalas correspond, respectively, to the MahÃÂvairocana and the Vajraà Âekhara sutras.
Abhiá¹£eka (kanjà Â) is a "ritual of passage" which initiates a student into esoteric practice, based on classical and medieval coronation rites.
Ajikan () is a form of ritual meditation on the Siddham syllable "A", the seed syllable (Skt. bëja mantra) for Vairocana. Kukai's Precious Key to the Secret Treasury gives a brief overview of the practice:
<blockquote> Visualize: a white lotus flower with eight petals, [above which is a full moon disc] the size of a forearm in diameter, [in which is] a radiant silvery letter A. Unite your dhyÃÂna with prajñàin an adamantine binding; Draw the quiescent prajñàof the tathÃÂgata [into your mind]. </blockquote>
Mikkyà  "functioned as a practical technology that had a direct bearing on medieval politics and economy". Fabio Rambelli interprets mikkyà  "as an ensemble of knowledge [...] implemented through interpretive strategies, repertoires of metaphors, and a general structuring of knowledge."
Buddhism justified writing in the Japanese language, whereas earlier periods favored Classical Chinese. Medieval Mikkyà  understood native Japanese poetry as sacred literature analogous to mantras, and many prominent waka poets, such as Henjà  and Saigyà Â, were Esoteric Buddhist clergy. Kà «kai is traditionally attributed with the invention of the syllabary and composing the . Ton'a relates a legend (among many circulating in medieval Japan) that Kà «kai developed the kana to facilitate the work of carpenters who were building the stupa at Mount Koya. While certainly apocryphal, "the systematic importation of Sanskrit...encouraged the emergence of the native script of kana characters", the derivation of the gojà «on from siddhaá¹ "point[s] to the reason underlying the belief widespread in the medieval period that Kà «kai was the inventor of the kana syllabary."