India made an important contribution to science. In ancient times, religion and science were inextricably linked.
Astronomy made great strides in India because the planets began to be regarded as gods, and their movements began to be closely observed.
Their study became essential because of their connection to changes in the seasons and weather conditions which were important for agricultural activities. The science of grammar and linguistics arose because the ancient brahmanas stressed that every Vedic prayer and mantra should be recited with meticulous precision.
In fact, the first result of the scientific outlook of Indians was the development of Sanskrit grammar. In the fifth century BC, Panini systematized the rules governing Sanskrit and produced a grammar called Ashtadhyayi. By the third century BC, mathematics, astronomy, and medicine began to develop separately. In the field of mathematics, the ancient Indians made three distinct contributions: the notation system, the decimal system, and the use of zero. The earliest epigraphic evidence for the use of the decimal system is in the beginning of the fifth century AD.
The Indian notational system was adopted by the Arabs who spread it in the Western world. The Indian numerals are called Arabic in English, but the Arabs themselves called their numerals hinds, and before they were adopted in the West they had been used in India for centuries.
They are to be found in the inscriptions of Ashoka which were inscribed in the third century BC. Indians were the first to use the decimal system. Aryabhata (ad 476— 500) was acquainted with it. The Chinese learnt this system from the Buddhist missionaries, and the Western world borrowed it from the Arabs when the latter came into contact with India. The zero was discovered by Indians in about the second century BC.
Indian mathematicians considered zero as a separate numeral, and it was used in this sense in sums of arithmetic. In Arabia, the earliest use of zero was in ad 873. The Arabs learnt and adopted it from India and spread it in Europe. Although both Indians and Creeks contributed to algebra, in Western Europe its knowledge was acquired not from Greece but from the Arabs who had acquired it from India.
The brick constructions of Harappa show that in north-western India, people had a substantial knowledge of measurement and geometry. Eventually the Vedic people may have benefited from this knowledge, which appears in the Sulvasutras of about the fifth century BC. In the second century BC, Apastamba produced a practical geometry for the construction of altars at which the kings could offer sacrifices.
It describes the acute angle, obtuse angle, and right angle. Aryabhata formulated the method for calculating the area of a triangle, which led to the origin of trigonometry. The most f amous work of this time is Suryasiddhanta, and no comparable work is to be found in the contemporary ancient East. The most renowned scholars of astronomy were Aryabhata and Varahamihira. Aryabhata lived in the fifth century, and Varahamihira in the sixth. Aryabhata calculated the position of the planets in accordance with the Babylonian method. He discovered the cause of lunar and solar eclipses.
The circumference of the earth, which he measured on the basis of speculation, is even today considered to be correct. He pointed out that the sun is stationary and the earth rotates. Aryabhata’s work is entitled Aryabhatiya was a landmark in the development of mathematical and astronomical knowledge, and is a distinct contribution to trigonometry.
On the basis of it, all the shapes and sizes of plots involved in gift making and property partition could be measured and assessed for fixation of rent or tax in early medieval times. This knowledge could also be used for the various measurements needed for the erection of temples and palaces, and other engineering work.
The use of the zero and the decimal system finds a place in the Aryabhatiya, but it was not put to any significant use in India. Once it spread westward through the Arabs, it began to be used for bookkeeping by Italian traders in the tenth century.
India’s loss in trade between the sixth and the tenth centuries can perhaps be linked to the neglect of the zero and decimal system. More accurate knowledge relevant to measurement and also to agro-astronomical calculations was made available by the algebra developed by Brahmagupta during the first half of the seventh century.
Varahamihira’s well-known work Brihatsamhita was written in the sixth century. He stated that the moon rotates around the earth and the earth rotates round the sun. He utilized several Greek works to explain the movement of the planets and some other astronomical problems. Although Greek knowledge influenced Indian astronomy, Indians doubtless pursued the subject further and made use of it in their observations of the planets.
Varahamihira’s plant and animal classifications enriched agricultural knowledge. Although his predictions relate to numerous social matters, the instructions given by him regarding the selection of sites for building houses tie up with the founding of new villages. Similarly, Varahamihira’s observations on the seasons and the weather could have been useful in planning the agricultural calendar.
He emphasized that the calendar should be constantly updated to keep pace with the change in the seasons. Varahamihira acted as a kind of astronomer-cum-astrologer. The office of jyotisi began in early medieval times, as is indicated in many land charters. In the rural areas, the priest-jyotisi became an integral part of the jajmam system. In the applied field, Indian craftsmen contributed much to the development of chemistry. Indian dyers invented lasting colours and they also discovered the blue colour. We may recall that Indian smiths were the first in the world to manufacture steel.