The Tuesday Edition

On continuity, weeks, and Easter 311 C.E.

Mark Slavonia (MJS) is an investor, a pilot, and an avid cyclist. He’s written plenty of WITIs, most recently about noon sundials, artificial water ski lakes, and Paternoster elevators. He posts other things that are interesting on his website.

Mark here. Today is Tuesday.

The sequence of days of the week, Sunday to Monday to Tuesday, has been running uninterrupted since (at least) Easter Sunday, 311 C.E. Nothing has stopped the inexorable march of the days.

The calendar of months and years has been revised from time to time, most famously when the Julian Calendar gave way to the Gregorian Calendar in 1582, but even then, when ten days were famously deleted, the days of the week continued unbroken. Julian Thursday, October 4, 1582 was followed by Gregorian Friday, October 15, 1582.

Why is this interesting?

Over 625,000 days have passed, nearly 100,000 perfect weeks, without a variance in this pattern, without a long week or a late weekend. If you went back in time 500,000 days from today, it might take some work to figure out what month and date it was due to the calendar revisions, but the day of the week? It’s definitely a Friday. 500,000 days is 71,428 weeks and four days ago.

Although seven-day weeks were practiced across the Near East in ancient times, things got a bit squishy during the Roman Empire, which used an eight day week. Somewhere in this period the sequence that we still follow now emerged. As the balance of power in the Roman Empire shifted east, the dominance of the seven-day Judeo-Christian week grew, so that it’s possible to count backward the days of the week all the way to the rule of Emperor Constantine and Easter Sunday, 311 CE. (Or so says Wikipedia, citing the work of the great historian of science Otto Neugebauer, whose word I’m willing to take on this.)

The week is such a strange, independent overlay to the months/years calendar that I often imagine trying to describe the system to an outsider. “The dominant civilization of the time adopted TWO independent calendars that ran simultaneously, a seven-day system used to mark religious observance and to signal periods of work and leisure, and another calendar based on the motion of the solar system to indicate particularly significant festivals and rituals.”

The Christmas/New Year holiday week has a way of throwing us off our rhythm, and disrupting our latent awareness of where in the week we are. Last week, I often found myself laboring to remember what day it was. But the seven-step march of the days continued uninterrupted, regardless of my attention. Odds are very good that whatever tomorrow may bring, it’ll be a Wednesday. (MJS)

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