- Lived:
- unknowable — the Baudhāyana Śulbasūtra, the oldest surviving manual of Indian geometry, was compiled somewhere around 800–500 BCE in the late Vedic world of north India, codifying altar-building lore that is older still
- Field:
- geometry and ritual mathematics — author, or authoring school, of the first of the Śulbasūtras, the "rules of the cord"
- The Big Idea:
- Because the gods' altars had to be exactly right, the priests of the fire ritual worked out real geometry — including the theorem we call Pythagoras's, written down and used in India before Pythagoras was born, and a value of √2 correct to five decimal places.
- In their words:
- "The rope stretched along the diagonal of an oblong produces by itself both the areas which the two sides of the oblong produce separately." (Baudhāyana Śulbasūtra, tr. after George Thibaut, 1875)
- If you remember one thing:
- The first mathematics in this book was built kneeling in the dirt with a rope and pegs, by men who never signed their work and never proved a theorem — and their unsigned, unproven geometry was correct to a few parts in a million.