WAS THE BEGINNING DAY OF THE
MAYA MONTH NUMBERED ZERO
(OR TWENTY) OR ONE?

BY
CHARLES P. BOWDITCH

CAMBRIDGE
THE UNIVERSITY PRESS
1901

WAS THE BEGINNING DAY OF THE MAYA MONTH NUMBERED ZERO (OR TWENTY) OR ONE?

Goodman, in his elaborate and valuable book on the Maya Inscriptions, has made up his Tables on the supposition that the beginning day of the month was not called Day 1, but Day 20, giving the day this number because in his view the Mayas counted the number of days which had passed and not the current or passing day. That is, the Mayas, according to Goodman, used the same plan in counting their days which we use in counting our minutes and hours and which we depart from in counting our days. Thus, when we speak of January 1, we do not mean that one day has passed since January came in, but that the month of December has passed and that we are living in the day which when completed will be the first day of January. But when we say that it is one o'clock, we do not mean that we are living in the hour which when passed will be the first hour of the day or half-day, but we mean that one whole hour of the day or half-day has fully passed. Goodman's idea is that the Mayas used this system in counting their days of the month, their kins, uinals, tuns, katuns, and cycles. In other words he considers that the beginning day of the month Pop was not 1 Pop, but 20 Pop, the beginning day of Uo was 20 Uo; that the beginning kin of a uinal was Kin 20, the beginning uinal of a tun was Uinal 18, the beginning tun of a katun was Tun 20, that the beginning katun of a cycle was Katun 20, and that the beginning cycle of a grand cycle was Cycle 13. The reason why Goodman substitutes 18 and 13 for 20 in the case of the uinals and cycles respectively is that these are the numbers of uinals and cycles which are needed to make one of the next higher units in his scale of numeration.

Without considering the truth or error of his view in regard to the cycles, katuns, etc., let us try to solve the following questions:

1st. Did the Mayas count the days of their month by the day which had passed, as we count our hours?

2d. Was the number which they gave to the beginning day of the month 0 or 20?

For our answers to these questions, let us turn to pages 46-50 of the Dresden Codex. These pages contain three rows of twenty month dates each, and each of these dates is reached with but two exceptions by counting forward from the preceding date the number of days specified in red at the bottom of the pages, the first date of each row on page 46 being the regular number of days distant from the last date of the same row on page 50.

In the first row of dates, we find that the third date on page 48 is 12 Chen. The number of days at the bottom of the page which need to be counted forward in order to reach the fourth date is 8. If the beginning day of the month were marked by the Mayas with 1, then the last day would be marked with 20, and by adding 8 days to 12 Chen, we should reach 20 Chen. But the date is not 20 Chen. The month is Yax,—the month immediately following Chen,—and the glyph which takes the place of the number has a form resembling two half-circles placed side by side. In other words, in this case 8 days from 12 Chen reach ? Yax, and as far as the first proposition is concerned, it is immaterial whether the form above given is called 0 or 20. Eight days have taken us out of the month Chen into the next month Yax, and to a day of that month which is not 1 Yax, but must be a day preceding 1 Yax, whether that is called 0 Yax or 20 Yax.

Again, the first date of the first row of month dates on page 50 is 10 Kankin, and the number at the bottom of the page to be added in order to reach the second date is