March 4, 2013

Last week the ‘Prince’ reported a groundswell, or at least a tremor, of support for a plan to make the Wednesday before Thanksgiving a de jure vacation day — currently, it is merely a de facto day off. The price would be starting classes a day earlier in September, which would cut into freshman advising and other festivities.

It’s not hard to think of ways to improve Princeton’s idiosyncratic calendar, though there’s rarely agreement on the proposed solutions. I’d be happy, however, if that Wednesday were an official holiday. My own experience is that lectures on the day before Thanksgiving are sparsely attended; typically only about a quarter of the class shows up, though it was somewhat better this year when Thanksgiving came less than three weeks after the end of fall break.

The biggest problem with the existing calendar is the huge gap between the last class in December and final exams in mid-to-late January. That break is over six weeks long, which means that everyone, both the students and professor, has forgotten the entire course by the time the exam rolls around.

No other school in our “peer group” has exams after Christmas. Harvard changed its calendar a few years ago so that exams are finished before the holiday. There are no exams in January, and, indeed, not much academic seems to happen then. From a distance it sounds like Harvard types just get a month off before things gear up again in late January. Winter in Cambridge can be so awful that spending it in California or Cancun would seem preferable, but Wintersession is popular, with activities like hip-hop and scuba diving (presumably in a heated indoor pool, not under the ice on the Charles River) among the 150 different offerings.

The cost of this calendar rearrangement is that Harvard’s fall courses start right at the beginning of September. The schedule change has also had some unexpected side effects on exams themselves. There are now relatively few in-class final exams at Harvard; in fact, the default is no in-class exam unless the faculty member explicitly chooses otherwise. My friend Harry Lewis, longtime computer science professor and former dean of Harvard College, says in his blog that there are powerful incentives to give take-home exams: since those have to be completed during reading period, all the work is over before the exam period and the holiday. Give an early take-home and be done in time for Christmas — sounds good to me.

Will Princeton ever change its calendar? I’m skeptical. Calendar reform is hard. One of the most vivid examples is the attempt by Pope Gregory XIII in 1582. The ancients had a pretty good idea of how long the year was, but 365 and a quarter days is about 11 minutes too long. According to Wikipedia, “The discrepancy results in a drift of about three days every 400 years. At the time of Gregory’s reform there had already been a drift of 10 days since Roman times, resulting in the spring equinox falling on 11 March instead of the ecclesiastically fixed date of 21 March, and moving steadily earlier in the Julian calendar.  Because the spring equinox was tied to the celebration of Easter, the Roman Catholic Church considered this steady movement in the date of the equinox undesirable.”

Gregory’s papal bull “Inter gravissimus” decreed that 10 days would simply be dropped from the calendar to bring things into sync. He also made sure this wouldn’t happen again in the near future by adding a secondary adjustment to leap years every 100 years (years divisible by 100 are not leap years) and even a tertiary adjustment every 400 years (2000 was a leap year).

The late 1500s were a time of religious strife in Europe — nothing new there — and Gregory’s quite sensible solution was rejected by Protestant countries, notably England and its colonies, which didn’t adopt the scheme until 1752, when the calendar went straight from Wednesday, Sept. 2 to Thursday, Sept. 14. (Can you imagine getting something similar through Congress today?)

Russia took a while longer to join the party; the Gregorian calendar wasn’t adopted there until 1918, after the revolution. Greece, another Eastern Orthodox country, waited until 1923, and there are still countries that do not use the Gregorian calendar today.

So what does this have to do with calendar reform at Princeton? Well, in the absence of a powerful, infallible leader like Pope Gregory, it’s unlikely that big changes are going to happen here. Maybe little ones are possible, though. Let’s see if we can make a start by declaring the Wednesday before Thanksgiving a holiday. Head home early, enjoy the extra time with your family — as you would have anyway, but with a clear conscience — and faculty won’t face the dilemma of whether to prepare a lecture for an empty room.


By : Brian Kernighan

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