Some References to Human Physiology in Jaina Scriptures

Summary

Jain scriptures provide not only metaphysical speculations but also observations on human physiology. In the essay 'Some References to Human Physiology in Jaina Scriptures', Muni Nandighoshavijay surveys various canonical texts that discuss the structure and functioning of the human body. The karmic treatise Karmagrantha and cosmological works such as Lokaprakāśa and Bṛhatsaṃgrahaṇī describe the body's framework of bones and joints. Six types of bone‑joints (saṃghayaṇa) are distinguished: vajraṛṣabhanārāca, ṛṣabhanārāca, nārāca, ardhā‑nārāca, kilikā and sevārta. The strongest joint, vajraṛṣabhanārāca, confers the greatest ability to perform actions, whereas the weakest, sevārta, is associated with limited capacity. The author explains that the distribution of different joints reflects variations in individuals' karmic status and that only those possessing the first type are able to withstand great misfortunes like Mahavira’s encounter with the demon Saṃgama. Jain writers also give surprisingly detailed accounts of embryology. The Tandulaveyāliya, Vicāra‑ratnākara and other treatises describe the embryo's development over the weeks and months of pregnancy. After conception, sperm and blood form a liquid, which then solidifies as tissues multiply; by the end of the first month the embryo weighs forty‑eight guñjas, while the second month brings cubic solidity, the third month determines the sex, and subsequent months see the formation of body parts and hair. The texts even estimate that the embryo becomes viable after the seventh month and may, because of karmic factors, remain in an embryonic state for up to twenty‑four years before rebirth. The essay cites passages describing reproductive age ranges for men and women, factors determining the sex of the offspring depending on the embryo's position in the womb, and the timing of fertilisation within twelve muhūrtas (nine hours and thirty‑six minutes). By juxtaposing these physiological observations with metaphysical explanations, the author shows how Jain thinkers integrated empirical knowledge into their soteriology. Human physiology is seen as conditioned by past actions but also as an instrument for liberation when one understands its structure and avoids harming living beings. The discussion illustrates the breadth of Jain scholarship, which embraced anatomy, embryology and medicine while always relating physical processes to ethical and cosmological principles.