History of Hindu Mathematics: A Source Book v1.c7.s10.75

v1.c7.s10.75

No explanation as to why the right to left arrangement was preferred in the word system is to be found in any of the ancient works. The following explanation suggests itself to us, and we believe that it is not far from the truth: The different words forming a number chronogram were to be so selected that the resulting word expression would fit in with the metre used. To facilitate the selection the number was first written down in numerical figures. The selection of the proper words would then, naturally, begin with the figure in the units place, and proceed to the left just as in arithmetical operations. This is in accordance with the rule "*aṅkânâṃ vâmato gatiḥ*," *i.e.*, 'the numerals proceed to the left,' which seems to have been very popular with the Indian mathematicians. The right to left arrangement is thus due to the desire of the mathematicians to look upon the process of formation of the word chronogram as a sort of arithmetical operation.