On 6/4/18, Jose Mario Quintana <[email protected]> wrote: > Harvey wrote: >> It's just the way it is.
I merely intended to inject some reality. Despite all of the discussions and arguments pro and con for various perspectives, nothing is going to change current civilization regarding dates and times. Everybody in these discussions can view it the way they want, accommodate their programming to the realities of the world, and life will go on. > ... Then, it gets even worse due to Greek and > Roman influence: one year of 12 months, numbered from 1 to 12 (when > the months are not explicitly named), and months of different numbers of > days, numbered from 1 to the last day, If you want all the gory details, go to pages 987-1003 of volume 4 of the 11th edition of the Encyclopaedia Britannica <https://books.google.com/books?id=mP4tAAAAIAAJ&printsec=frontcover&dq=editions:XzxQJyk6QDAC&hl=en&sa=X&ved=0ahUKEwil-YTBqLvbAhUrzoMKHRxCDaAQuwUIRDAF#v=onepage&q&f=false>. In brief, the old Roman calendar (as revised by Julius Caesar) started in what is now March. It had months with the number of days alternating between 31 and 30 (except the last month, February, had 29). (Another way of looking at it is that the odd-numbered months had the odd number of days, 31, and the even-numbered months had the even number of days, 30, except for the last month, February.) The months had numbers as their names. (We still have the names September through December from the original 7th through 10th months. Using our way of naming them, the 5th and 6th months would have been Quintember and Sextember.) After Julius Caesar's death, Quintember's name was changed to July to honor him. Later, Augustus Caesar had such a high estimation of himself that he renamed Sextember to August and, in order to also have 31 days in that month like Julius Caesar, he "stole" a day from the last month, February, leaving it with only 28 days. However, this created three 31-day months in a row, and so the next several months were adjusted in terms of 31 and 30 days, so that there would be no more than 2 months back-to-back with 31 days. At this time the equinox occurred on March 25, but, because there was no adjustment for the slight difference between the calendar year (even with leap years) and the true solar year, the equinox had precessed to March 21 by the time of the Council of Nicaea in 325 AD (when the date of Easter was determined). At some point in history, the year switched to start on January 1 rather than March 25 (which was the original equinox date and the date of the Annunciation, 9 months before Christmas). However, that was not the case in England, which retained New Year's Day on March 25 and did not drop days at the time of the Gregorian calendar reform. (One of the purposes of the 10-day reform was to get the equinox back on the date it was at the Council of Nicaea, March 21--by 1582 it was on March 11.) Finally, in 1750 England passed a law that, beginning in 1752, 11 days (an extra day had accumulated by that time) would be dropped from the calendar to synchronize with the rest of Europe and that the civil year would begin on January 1 rather than March 25. This created an interesting situation because anyone who had been born between January 1 and March 24 had not only a change in date but also a change in their birth year. For example, George Washington was originally born February 11, 1731 (O.S. = Old Style), but, with the calendar reform, that changed to February 22, 1732 (N.S. = New Style)--the date we know nowadays. It took a long period of time for people in both England and the American colonies to become accustomed to this change and to change all the various records and references to dates. > and the number of days of one > particular month depends on awfully complicated rules! Actually, it's rather easy--it all depends on the number 4. If you're dealing with century years (100 years, ending with 00), then it's a leap year if the century year is divisible by 400 (100x4); otherwise it's not a leap year. If you're dealing with a non-century year, then it's a leap year if it's divisible by 4; otherwise it's not a leap year. (Always do the century test first--then the rule is simple.) Technically, the Gregorian "fix" very slightly over-corrects the calculation, and so some have suggested the following preliminary step (neither you nor I will be around when this might become necessary): if you're dealing with millenial years (1000 years, ending with 000), then if the millennial year is divisible by 4000 (1000x4), it is NOT a leap year. But even that needs correction about every 20,000 years! I won't be here, but with all this talk about time, I think it will be very interesting to see what happens (or what workarounds will be developed) when the Unix time counter (2^31) turns over to zero in 2038--it's Y2K all over again! But that's also right around the same time that Social Security is forecast to run out of money. Hmmm..... Harvey ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
