bShad-rgyud (The Explanatory Tantra)

About bShad-rgyud (The Explanatory Tantra)

The bShad-rgyud, the Explanatory Tantra, is the second of the four tantras of the rGyud-bzhi. Where the rTsa-rgyud names, the bShad-rgyud explains. Its 31 chapters unpack the theoretical foundation of Tibetan medicine: anatomy, embryology, physiology, the three nyes pa in full detail, the seven bodily constituents, pathology, hygiene, diet, and a pharmacological overview.

The Explanatory Tantra is the most systematically philosophical of the four tantras and the most heavily influenced by Indian medical literature. Its embryology chapter, describing week-by-week fetal development, karmic factors in conception, and the differentiation of tissues, parallels Ayurvedic material in Suśruta Saṃhitā and Caraka Saṃhitā and supplies one of the most detailed pre-modern accounts of development in any Asian medical tradition.

The bShad-rgyud develops the doctrine of the three nyes pa into its operational form. Each of rLung, mKhris-pa, and Bad-kan is subdivided into five forms with specific seats, functions, and pathologies. The text teaches which locations in the body each subtype governs, what activities they support, and how their disturbance produces specific classes of disease. This fivefold subdivision is the foundation of clinical reasoning in Sowa Rigpa and governs every diagnostic and therapeutic decision in the Man-ngag rgyud.

Alongside humoral theory the tantra describes the body's channels (rtsa), the five solid (don) and six hollow (snod) organs, the vital points, the metabolic fire (me-drod), and the seven lus-zungs whose sequential transformation produces bodily tissue and reproductive essence. The seasonal and daily hygiene chapters prescribe diet, sleep, sexual conduct, bathing, and mental discipline — the bShad-rgyud treats hygiene as medicine's first intervention, not a supplement to it.

The final chapters of the Explanatory Tantra introduce pharmacology in general terms: the six tastes, three post-digestive tastes, eight potencies, seventeen qualities, and twenty functions of medicinal substances. Specific formulas belong to the Phyi-ma rgyud. The bShad-rgyud provides the theoretical grammar on which those formulas will later be built.

Structure

The bShad-rgyud comprises 31 chapters. The opening chapters cover the body in health: conception and embryology (chapter 2 is the famous week-by-week account), anatomical classification, the three nyes pa in their fivefold subdivisions (chapters 5–7), the seven bodily constituents and three wastes (chapter 8), physiological actions, life span, signs of death, and the causes and conditions of disease. Middle chapters cover hygiene: daily conduct, seasonal conduct, occasional conduct, and dietary regulation. Later chapters treat pathology — the routes, locations, and patterns of disease. The closing chapters introduce pharmacological theory and the qualities of the ideal physician. Traditional editions run roughly 180 folios, with chapters of uneven length.

Key Teachings

The central theoretical teaching is the fivefold subdivision of each nyes pa. rLung divides into life-sustaining (srog-'dzin), ascending (gyen-rgyu), pervasive (khyab-byed), fire-accompanying (me-mnyam), and downward-clearing (thur-sel), each with its own seat, action, and pathology. mKhris-pa divides into digestive, color-transforming, accomplishing, sight-providing, and complexion-clearing. Bad-kan divides into supporting, decomposing, tasting, satisfying, and connecting. Clinical diagnosis reasons about which subtype in which location is disturbed.

The embryology chapter describes conception as the meeting of white father-drop, red mother-drop, and consciousness, followed by thirty-eight weeks of fetal development described stage by stage. Each week is correlated with the formation of specific tissues, organs, and sensory capacities. Karmic factors shaping constitution, sex, and life span are woven in without displacing the physiological account.

The seven lus-zungs — chyle (dwangs-ma), blood, flesh, fat, bone, marrow, and reproductive essence — describe a seven-stage metabolic transformation of food through the metabolic fire, with each stage taking approximately one day in health. Disturbance of the fire generates disease in the corresponding constituent.

The hygiene chapters treat Sowa Rigpa as first and foremost a preventive discipline. Correct daily conduct (sleep, elimination, bathing, exercise, sexual activity), correct seasonal conduct (adjustments for winter, spring, summer, monsoon, autumn, late autumn), and correct dietary regulation are taught as the primary medical interventions — medicine and external therapies enter only when hygiene has failed.

The pathology chapters teach the six causes, four conditions, six entry routes, fifteen locations, and nine outcomes of disease, giving the physician a systematic framework for tracing any specific illness back to its origin in humoral disturbance.

Commentary Tradition

The bShad-rgyud is commented on in depth in the Vaidurya sngon po (Blue Beryl) of Desi Sangye Gyatso, 1688, whose embryology illustrations in the medical thangkas are particularly well known. The Zur and Jang commentarial traditions, represented by Zurkhar Lodro Gyalpo and Jangpa Namgyal Dragzang, differ chiefly on details of the fivefold subdivisions and the interpretation of the embryology chapter. Kyempa Tsewang wrote an influential 15th-century commentary on the Explanatory Tantra that remains in use at Men-Tsee-Khang.

Translations

Barry Clark's The Quintessence Tantras of Tibetan Medicine (Snow Lion, 1995) translates the bShad-rgyud in full alongside the Root Tantra. The embryology chapter has been translated and studied separately by Frances Garrett in Religion, Medicine and the Human Embryo in Tibet (Routledge, 2008). Men-Tsee-Khang has published Tibetan-English editions for student use in Dharamsala. Dashiev's 1988 Russian translation includes the Explanatory Tantra in full. Chinese and Mongolian editions circulate widely.

Significance

The bShad-rgyud is the theoretical core of Tibetan medicine. It is the tantra in which every abstract term used in clinical practice is defined, every anatomical referent named, every physiological process described. Without its framework the disease-by-disease protocols of the Man-ngag rgyud could not be read. Its embryology chapter is a landmark in pre-modern developmental biology, and its fivefold subdivision of the three nyes pa remains the living grammar of clinical reasoning in contemporary Sowa Rigpa practice.

Ayurvedic Parallel

The bShad-rgyud's structure closely tracks Vāgbhaṭa's Aṣṭāṅga Hṛdaya, especially in the sections on anatomy, dietetics, and daily conduct (dinacaryā). The embryology chapter parallels Suśruta Saṃhitā Śārīrasthāna. The seven lus-zungs map directly onto the Ayurvedic sapta dhātu, and the fivefold subdivision of the nyes pa corresponds to the five vāyus, five pittas, and five kaphas of classical Ayurveda. See Ayurveda.

TCM Parallel

The five solid (don) and six hollow (snod) organs correspond loosely to TCM's zang-fu system, though the anatomical assignments differ. The emphasis on seasonal regulation of conduct parallels the Huang Di Nei Jing's chapters on seasonal attunement.

Connections

The bShad-rgyud is the second of the four tantras of the rGyud-bzhi. Its theoretical framework is the precondition for reading the Man-ngag rgyud and the Phyi-ma rgyud.

The three nyes pa and their fivefold subdivisions are treated at rLung, mKhris-pa, and Bad-kan.

The pharmacological theory introduced in later chapters is elaborated in Shel gong shel phreng (Crystal Rosary) and Me tog phreng ba (Garland of Flowers).

The definitive commentary is the Vaidurya sngon po.

Section hub: Sowa Rigpa. All texts: Tibetan Medical Texts.

Further Reading