Union of wisdom and emptiness
Mahāmudrā (Sanskrit: महामुद्रा, Tibetan: ཕྱག་ཆེན་, Wylie: "phyag chen", THL: "chag-chen", contraction of Tibetan: ཕྱག་རྒྱ་ཆེན་པོ་, Wylie: "phyag rgya chen po", THL: "chag-gya chen-po") literally means "great seal" or "great imprint" and refers to the fact that "all phenomena inevitably are stamped by the fact of wisdom and emptiness inseparable". Mahāmudrā is a multivalent term of great importance in later Indian Buddhism and Tibetan Buddhism which "also occurs occasionally in Hindu and East Asian Buddhist esotericism."
The name also refers to a body of teachings representing the culmination of all the practices of the New Translation schools of Tibetan Buddhism, who believe it to be the quintessential message of all of their sacred texts. The practice of Mahāmudrā is also known as the teaching called "Sahajayoga" or "Co-emergence Yoga". In Tibetan Buddhism, particularly the Kagyu school, Sahaja Mahāmudrā is sometimes seen as a different Buddhist vehicle (yana), the "Sahajayana" (Tibetan: "lhen chig kye pa"), also known as the vehicle of self-liberation.
Jamgon Kongtrul, a Tibetan nonsectarian (THL: ri-mé) scholar, characterizes mahāmudrā as the path to realizing the "mind as it is" (Wylie: "sems nyid") which also stands at the core of all Kagyu paths. He states, "In general, Mahāmudrā and everything below it are the ‘mind path’ " (Wylie: "sems lam") Mahāmudrā traditionally refers to the quintessence of mind itself and the practice of meditation in relation to a true understanding of it.
History.
The usage and meaning of the term "mahāmudrā" evolved over the course of hundreds of years of Indian and Tibetan history, and as a result, the term may refer variously to "a ritual hand-gesture, one of a sequence of 'seals' in Tantric practice, the nature of reality as emptiness, a meditation procedure focusing on the nature of Mind, an innate blissful gnosis cognizing emptiness nondually, or the supreme attainment of buddhahood at the culmination of the Tantric path."
According to Jamgon Kongtrul, the Indian theoretical sources of the mahāmudrā tradition are Yogacara and tathagatagarbha (buddha-nature) texts such as the "Saṃdhinirmocana Sūtra" and the "Mahāyānottaratantraśāstra". The actual practice and lineage of mahāmudrā can be traced back to wandering mahasiddhas (great adepts) during the Indian Pala Dynasty (760-1142), beginning with the 8th century siddha Saraha.
Saraha's "Dohas" (songs or poems in rhyming couplets) are the earliest mahāmudrā literature extant, and promote some of the unique features of mahāmudrā such as the importance of pointing-out instruction by a guru, the non-dual nature of mind, and the negation of conventional means of achieving enlightenment such as samatha-vipasyana meditation, monasticism, rituals, tantric practices and doctrinal study in favor of more the direct methods of mahāmudrā 'non-meditation' and 'non-action'. These teachings also became the wellspring for the body of instructions eventually known as the mind teachings of Tibet associated with mahāmudrā of the Kagyu lineages. Later Indian and Tibetan masters such as Padmavajra, Tilopa, and Gampopa incorporated mahāmudrā into tantric, monastic and traditional meditative frameworks.
Etymology.
It has been speculated that the first use of the term was in the c. 7th century "Mañjuśrīmūlakalpa", in which it refers to a hand gesture.
The term is mentioned with increasing frequency as various Buddhist tantras developed further, particularly in the Yogatantras, where it appears in "Tattvasaṁgraha (Compendium of Reality)" and the "Vajraśekhara (Vajra-peak)". In these sources, "mahāmudrā" also denotes a hand gesture, now linked to three other hand mudrās—the action ("karma"), pledge ("samaya"), and "dharma" mudrās—but also involves "mantra recitations and visualizations that symbolize and help to effect one's complete identification with a deity's divine form or awakening Mind (bodhicitta)."
In Mahāyoga tantras such as the "Guhyasamāja tantra", mahāmudrā "has multiple meanings, including a contemplation-recitation conducive to the adamantine body, speech, and Mind of the tathāgatas; and the object—emptiness—through realization of which 'all is accomplished,'" and it is also used as a synonym for awakened Mind, which is said to be "primordially unborn, empty, unarisen, nonexistent, devoid of self, naturally luminous, and immaculate like the sky."
The idea of "mahāmudrā" emerges as a central Buddhist concept in the "Anuttarayoga Tantras" (also known as "Yoginītantras") like the "Hevajra", "Cakrasaṁvara", and "Kālacakra." 
According to Roger Jackson, in these tantras, mahāmudrā has multiple referents. It can refer to completion stage practices which work with forces in the subtle body ("sūkṣma śarīra") to produce a divine form and "a luminous, blissful, nonconceptual gnosis." In this context, it is seen as the highest practice which transcends and perfects all previous ones and leads to a direct realization of the nature of mind. In the context of sexual yoga, mahāmudrā can also refers to a yogi's female consort. Furthermore, the term mahāmudrā can also refer to the ultimate truth and the ultimate realization ("mahāmudrā-siddhī") in Buddhist tantra. As such, it is the "great seal" which marks all phenomena, i.e. Suchness (tathata), emptiness, the "unchanging bliss beyond object and subject, shape, thought, or expression".
The tantric scholar Aryadeva summarises the meaning of mahāmudrā as: "the discussion of how to attain mahāmudrā entails methods for meditating on Mind itself as something having voidness as its nature".
According to Reginald Ray, the term "Mudrā" denotes that in an adept's experience of reality, each phenomenon appears vividly, while the term "Mahā" ("great") refers to the fact that it is beyond concept, imagination, and projection.
Indian sources.
All of the various Tibetan mahāmudrā lineages originated with the Mahasiddhas of medieval India (c. 8th to 12th centuries). The earliest figure is the tenth century poet yogi Saraha, and his student Nagarjuna (this tantric figure not to be confused with the earlier philosopher Nagarjuna). Saraha's collections of poems and songs, mostly composed in the apabhramsa language are the earliest Indian sources for mahāmudrā teachings, aside from the Buddhist tantras.
Other influential Indian mahasiddhas include Tilopa, his student Naropa and Naropa's consort Niguma. Tilopa's "Ganges Mahāmudrā" song is a widely taught short mahāmudrā text. Niguma is an important source for the Shangpa Kagyu lineage.
Tilopa's pupil Maitripa (c.  1007–1085) became the principal master of mahāmudrā in India during his time and most lineages of mahāmudrā are traced from Maitripa. Maitripa was a very influential figure of the eleventh century, a scholar and tantrika who widely taught the "Ratnagotravibhāga", a text which is widely seen as bridging the sutric Mahayana and Anuttarayogatantra views. He composed commentaries on the buddhist dohas, and his works include a collection of 26 texts on "non-conceptual realization" ("amanasikara"), which are a key Indian source of mahāmudrā teachings that blend sutra and tantra, and teach an instantaneous approach to awakening.
One of Maitripa's students was the Kadam scholar Atisha, who taught mahāmudrā to his pupil Dromtönpa (1004–63) who decided not to make mahāmudrā a part of the Kadam tradition. Another pupil of Maitripa, Marpa Lotsawa, also introduced mahāmudrā to Tibet and his disciple Milarepa is also a central figure of this lineage. Another important figure in the introduction of mahāmudrā to the area is Vajrapani, yet another student of Maitripa. His student, Asu, also was a teacher of Rechungpa (1084-1161), one of Milarepa's pupils.
Gampopa, a key figure of the Kagyu school, refers to three important cycles of Indian texts which discuss Mahāmudrā as his main sources:
This classification existed since the time of Butön Rinchen Drup (1290-1364).
Indian sources of mahāmudrā were later compiled by the seventh Karmapa Chödrak Gyatso (1454-1506) into a three-volume compilation entitled "The Indian Mahāmudrā Treatises" (Tib. "Phyag rgya chen po 'i rgya gzhung"). This compilation includes the above three collections, along with the "Anavilatantra" and texts that teach a non-tantric "instantaneous"approach to the practice by an Indian master named Śākyaśribhadra.
Tibetan traditions.
Mahāmudrā is most well known as a teaching within the Kagyu school of Tibetan Buddhism. However the Gelug and Sakya schools also practice mahāmudrā. The Nyingma school and Bon practise Dzogchen, a cognate but distinct method of direct introduction to the principle of śūnyatā. Nyingma students may also receive supplemental training in mahāmudrā, and the Palyul Nyingma lineage preserves a lineage of the "Union of mahāmudrā and Ati Yoga" originated by Karma Chagme.
Kagyu tradition.
Gampopa Sönam Rinchen (1079-1153), a Kadam monk who was a student of the lay tantric yogi Milarepa, is a key figure in the Kagyu tradition. He is responsible for much of the development of Kagyu monastic institutions and for recording the teachings of the lineage in writing. He synthesized the Mahayana Kadam teachings with the tantric teachings he received from Milarepa and developed a unique system of mahāmudrā which he often taught without tantric empowerment, relying instead on guru yoga.
Mahāmudrā is defined by Gampopa as "the realization of the natural state as awareness-emptiness, absolutely clear and transparent, without root". Gampopa also states that mahāmudrā is "the paramita of wisdom, beyond thought and expression." Gampopa taught mahāmudrā in a five part system to his disciples, one of his most well known disciples, Phagmo Drupa (1110-1170) became a very successful teacher who continued to teach this five part system and eight "junior" kagyu lineages are traced to him. This "Five-Part Mahāmudrā" system became one of the main ways that Mahāmudrā was transmitted in Kagyu lineages after Gampopa.
The tradition which follows Gampopa is called Dakpo Kagyu. A key Mahāmudrā author of this tradition is Dakpo Tashi Namgyal, well known for his "Mahāmudrā: The Moonlight." Karma Kagyu Karmapas like the ninth Karmapa Wangchuk Dorje also composed important Mahāmudrā texts. A development of these later mahāmudrā writers is the integration of the common Mahayana teachings on samatha and vipasyana as preliminaries to the practice of mahāmudrā.
Three types of teaching.
The Kagyu lineage divides the mahāmudrā teachings into three types, "sutra mahāmudrā," "tantra mahāmudrā," and "essence mahāmudrā," in a formulation that appears to originate with Jamgon Kongtrul. Sutra mahāmudrā, as the name suggests, draws its philosophical view and meditation techniques from the sutrayana tradition. Tantric mahāmudrā employs such tantric techniques as tummo, dream yoga, and ösel, three of the Six Yogas of Naropa. Essence mahāmudrā is based on the direct instruction of a qualified lama, known as pointing-out instruction.
As a path beyond sutra and tantra.
Kagyu lineage figures such as Gampopa presented a form of mahāmudrā that was said to transcend the vehicles of sutrayana and vajrayana. According to Karl Brunnholzl, Gampopa saw Mahāmudrā as a third path that was neither sutra nor tantra which he called "the path of prajña" and "the path of suchness," and which "relies on blessing and is for those who are intelligent and of sharp faculties." Brunnholzl adds that for Gampopa, the mahāmudrā path of "taking direct perceptions as the path" relies on introduction by a genuine guru to the luminous dharmakaya and thus:
Through having been taught an unmistaken instruction of definitive meaning like that, one then takes native mind as the path, without separating the triad of view, conduct, and meditation in terms of this connate mind about which one has gained certainty within oneself.
Gampopa also stated that mahāmudrā was "the highest path that actually transcends both sutra and tantra." Brunnholzl further states that "In practice, most of Gampopa's preserved teachings consist primarily of sutra-based instructions and then conclude with Mahāmudrā, either not teaching the path of mantra at all or mentioning it only in passing."
The Kagyu tradition bases their mahāmudrā teachings on the works of Indian mahasiddhas like Saraha and Maitripa. According to Klaus-Dieter Mathes,
 ;templatestyles src="Template:Blockquote/styles.css" / ;Later Bka´ brgyud pas defended their not specifically Tantric or sūtra mahāmudrā tradition by adducing Indian sources such as the Tattvadaśakaṭīkā or the Tattvāvatāra. These belong to a genre of literature which the Seventh Karmapa Chos grags rgya mtsho (1454–1506) called "Indian mahāmudrā-Works" (phyag chen rgya gzhung).
Mathes investigated the practice described in these mahāmudrā works and found that it is not necessarily Tantric. In Saraha's dohās, it is simply the realization of Mind's co-emergent nature with the help of a genuine guru. Maitrīpa (ca. 1007–1085) uses the term Mahāmudrā for precisely such an approach, thus employing an originally Tantric term for something that is not a specifically Tantric practice. It is thus legitimate for later Kagyupas to speak of Saraha's mahāmudrā tradition as being originally independent of the Sūtras and the Tantras. For Maitrīpa, the direct realization of emptiness (or the co-emergent) is the bridging link between the Sūtras and the Tantras, and it is thanks to this bridge that mahāmudrā can be linked to the Sūtras and the Tantras. In the Sūtras it takes the form of the practice of non-abiding and becoming mentally disengaged, while in the Tantras it occupies a special position among the four mudrās.
The Kagyu teachings of mahāmudrā became a