The Charaka Samhita, compiled in its current form c. 100 AD from older oral tradition, systematizes Ayurvedic internal medicine into 8 sthanas (sections) and 120 chapters. It establishes principles of clinical diagnosis based on the three doshas (Vata, Pitta, Kapha), a pharmacology of more than 1,000 plants and minerals, and a medical code of ethics that precedes the Hippocratic Oath in some respects. It defines disease as a systemic imbalance and health as dynamic equilibrium. Translated into Persian and Arabic c. 8th century, it was directly incorporated by Al-Razi and Ibn Sina into their medical encyclopedias. The Bṛhattrayī ('Great Trio') of Ayurvedic texts includes the Charaka Samhita, the Sushruta Samhita, and the Ashtanga Hridayam.