Lagadha: the Vedanga Jyotisha · Chapter 2 of 2

#The question of the date

#The evidence of the solstices

The Vedanga Jyotisha says where the solstices fall among the nakshatras: the winter solstice at the beginning of Dhanishta and the summer solstice in the middle of Ashlesha.

Because of precession, the solstices slowly move through the nakshatras — about one nakshatra in a thousand years. So the positions Lagadha records point to a particular period.

#The early view

The Indian scholars B. G. Tilak (1925) and S. B. Dikshit computed when the solstices stood at those points, and dated the text to about 1400 BCE or earlier.

#The late view

The historian David Pingree dated the text to "not very many years before or after 400 BCE". His arguments:

• its language is post-Vedic;
• it seems to draw on ideas found in Pingala's work on metre;
• its methods resemble Mesopotamian astronomy of the Achaemenid (Persian) period.

#Varahamihira's testimony

A thousand years later, Varahamihira wrote:

At one time, the Sun's southward course commenced on his reaching the middle of Ashlesha and its northward course on its reaching the beginning of Dhanishta. This must have been the case, as we find it so recorded in ancient books. Whereas at present the one course of the Sun commences at the beginning of Cancer, and the other at the beginning of Capricorn (Brihat Samhita 3.1–2).

So Varahamihira knew the Vedanga Jyotisha's solstice positions as "ancient", knew that the sky had changed since, and said the change could be checked by observation (Brihat Samhita 3.3).

#Holding both views

The two views can be partly reconciled: the solstice positions may preserve an old observation, handed down, while the text in its present form was composed later. That would explain both the early sky and the late language.

This book does not decide the question. A student should know both views and the evidence for each — and notice that the argument itself is an example of astronomy used as a clock for history.

#Summary

• The Vedanga Jyotisha puts the winter solstice at the start of Dhanishta and the summer solstice in mid-Ashlesha.
• Tilak and Dikshit dated it from these positions to about 1400 BCE; Pingree, from its language, its debts and its Mesopotamian parallels, to about 400 BCE.
• Varahamihira recorded the same positions as "ancient" and noted that the solstices had moved (Brihat Samhita 3.1–3).
• The positions may preserve an older observation within a later text.

#Exercises

1. Where does the Vedanga Jyotisha place the solstices?
2. Why can solstice positions be used to date a text?
3. What three arguments did Pingree give for a late date?
4. What did Varahamihira say about these positions?

Answers: 1. The winter solstice at the beginning of Dhanishta, the summer solstice in the middle of Ashlesha. 2. Because precession moves the solstices slowly through the nakshatras, about one nakshatra in a thousand years. 3. Its post-Vedic language, its debt to Pingala, and its resemblance to Achaemenid-period Mesopotamian astronomy. 4. That they were recorded in ancient books, that the solstices now fell at the starts of Cancer and Capricorn, and that the change could be checked by observation.