Siddhanta Siromani (Ganitadhyaya / Grahaganita quarter only)
Siddhanta Siromani (Ganitadhyaya / Grahaganita quarter only): what it is, what it added, and what we retired from it.
Siddhanta Siromani (Grahaganita part) - Bhaskara II, translated by D. Arkasomayaji.
Edition consulted: English Exposition and Annotation, Kendriya Sanskrit Vidyapeetha, Tirupati Series No. 29, 1990.
What kind of text this is
This book is not a full translation. It gives only the math parts of the work. The editor left out the Goladhyaya section. Because of this, the lines where Bhaskara dates his own life do not appear here.
What it contributed
circular-reasoning-admitted - novel. Bhaskara checks his own work. He admits that finding planet cycles can turn in circles. No human lives long enough to watch a full loop of slow stars. So he takes the base numbers from older texts on trust. This honest admission shows true self-criticism. He tests his claims against hard facts.
dissent-answered-by-smrti - refinement. Bhaskara lived long after Aryabhata. Aryabhata taught that the Earth spins. But Bhaskara chose a still Earth instead. The editor notes he did this out of respect for old belief. This shows that ancient thought did not always run straight toward truth.
predecessor-corrected-by-name - novel. Bhaskara names past writers and fixes their math. He points out errors by Lalla and tests them with clear math checks. He shows that Indian math grew through open debate and correction.
samhita-branch-definition - refinement. Bhaskara keeps math apart from omens. He says sky math is the true root of Jyotisha. Math tracks paths in the sky. Giving meaning to those paths is a separate step.
ganita-serves-phala - novel. Star math finds true spots in the sky. Adding fortune to those spots came as a later layer. The book keeps the math clean and free from fortune telling.
ayanamsa-choice-argued - novel. Bhaskara compares speeds for the drift of the stars. He picks a rate based on sun-shadow tests at the solstices. He relies on real tools and sights rather than blind faith.
Reading the text yourself
We cite and quote. We do not reprint full books. Most modern translations are under copyright. Older public texts sit on the Internet Archive. Our notes give book and verse so you can check every point in your own copy.
More of the corpus
All sources and grahas· The writing that uses them· How a reading is computed