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Lewis Carroll – computing the day of the week for any given date (1887)

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Re: Lewis Carroll – computing the day of the week for any given date (1887)

#101

Post by ColinWright »

mark-r wrote: post #99
ColinWright wrote: post #3

This is very similar to the method I use and, after conversation with him, the method Art Benjamin uses. It's trivial to do in 10 to 15 seconds, though it requires practice, a very small amount of memorisation[0], and a small amount of mental arithmetic. I use it regularly, partly to keep in practice, and partly because once you have the skill you find it's surprisingly useful. JH Conway used a different technique[1]…

I don't quite understand. Your magic month numbers are 3 digits, but you only use one digit in your example. And how does substituting 2012 work, when 2012 was a leap year but 1900 wasn't?

> 144 : Jan, Feb, Mar

So Jan=1, Feb=4, Mar=4

> 025 : Apr, May, Jun

So Apr=0, May=2, Jun=5

... and so on.

And we can substitute 2012 for 1900 because we make a correction in Jan and Feb in leap years. Knowing that 1900 was not a leap year means we don't make the correction, but 2012 was a leap year so we do.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#102

Post by jjtheblunt »

jjtheblunt wrote: post #51
jrochkind1 wrote: post #41

Earlier quoted context omitted.

For some reason part participles are particularly hard for me too (native English speaker who speaks no other languages fluently). (they must just be a mess in English? I can't imagine how non-native speakers ever get any of them) I'm going to go with swutcheted

For entertainment look up Germanic string and weak verbs.

autocorrect unspelling above: string -> strong

( https://en.wikipedia.org/wiki/Germanic_strong_verb )

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#103

Post by sudosysgen »

schoen wrote: post #94
dotancohen wrote: post #93

Earlier quoted context omitted.

He didn't ascribe the Biblical narrative to the convention, he mentioned that they match. They could match due to coincidence, due to having a common ancestor, or due to the Biblical narrative itself following the extent (as you claim) standard.

I wrote "mostly ultimately because of", so I did mean to say that I thought the Biblical narrative was the historical reason that most cultures and languages that use this numbering did so. I'm pretty curious about this question, which I've previously asked in the form of "for how long has there been a worldwide consensus about which day of the week it is?". One answer that I heard is sort of akin to sudosysgen's acc…

It most likely comes from Greek, as the first time the Bible would be translated in a language where days had names. Some Greek calendars used the seven day week which seems to originate from the Sumerians, and naturally the day of the Sun would be the choice for the first day in the Greek pantheon.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#104

Post by canadianfella »

jihadjihad wrote: post #6
ColinWright wrote: post #3

This is very similar to the method I use and, after conversation with him, the method Art Benjamin uses. It's trivial to do in 10 to 15 seconds, though it requires practice, a very small amount of memorisation[0], and a small amount of mental arithmetic. I use it regularly, partly to keep in practice, and partly because once you have the skill you find it's surprisingly useful. JH Conway used a different technique[1]…

> which I have swutch to That's a past participle I've never seent before

[dead]

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#105

Post by mark-r »

ColinWright wrote: post #101
mark-r wrote: post #99

Earlier quoted context omitted.

I don't quite understand. Your magic month numbers are 3 digits, but you only use one digit in your example. And how does substituting 2012 work, when 2012 was a leap year but 1900 wasn't?

> 144 : Jan, Feb, Mar So Jan=1, Feb=4, Mar=4 > 025 : Apr, May, Jun So Apr=0, May=2, Jun=5 ... and so on. And we can substitute 2012 for 1900 because we make a correction in Jan and Feb in leap years. Knowing that 1900 was not a leap year means we don't make the correction, but 2012 was a leap year so we do.

Thanks. Would have been easier to grasp though if you'd phrased it like

> 1,4,4 : Jan, Feb, Mar.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#106

Post by D-Coder »

jihadjihad wrote: post #6
ColinWright wrote: post #3

This is very similar to the method I use and, after conversation with him, the method Art Benjamin uses. It's trivial to do in 10 to 15 seconds, though it requires practice, a very small amount of memorisation[0], and a small amount of mental arithmetic. I use it regularly, partly to keep in practice, and partly because once you have the skill you find it's surprisingly useful. JH Conway used a different technique[1]…

> which I have swutch to That's a past participle I've never seent before

"swutch"

Compilation error at line 173.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#107

Post by schoen »

sudosysgen wrote: post #103
schoen wrote: post #94

Earlier quoted context omitted.

I wrote "mostly ultimately because of", so I did mean to say that I thought the Biblical narrative was the historical reason that most cultures and languages that use this numbering did so. I'm pretty curious about this question, which I've previously asked in the form of "for how long has there been a worldwide consensus about which day of the week it is?". One answer that I heard is sort of akin to sudosysgen's acc…

It most likely comes from Greek, as the first time the Bible would be translated in a language where days had names. Some Greek calendars used the seven day week which seems to originate from the Sumerians, and naturally the day of the Sun would be the choice for the first day in the Greek pantheon.

I just looked in the Septuagint and (I guess unsurprisingly) it uses ἡμέρα μία, ἡμέρα δευτέρα, ἡμέρα τρίτη. So it wasn't literally directly in the translation process. One could also say that the Genesis text is counting days rather than naming them, as Genesis 1:5 for says יוֹם אֶחָד ('one day') whereas the "name" of the day in Hebrew is יוֹם רִאשׁוֹן ('first day').

This author argues that the "the Jewish, biblical week and the planetary week of astrological origin" were combined in Rome rather than Greece, while agreeing that there are earlier antecedents for the use of the seven-day week.

https://blogs.fu-berlin.de/zodiacblog/2022/05/02/the-origins...

Wikipedia on "nundinae" seems to roughly agree with this interpretation:

> The 7-day week first came into use in Italy during the early imperial period. For a time, both systems were used together, but the nundinae are seldom mentioned in extant sources after the Julio-Claudian period. The nundinal cycle had probably fallen out of use by the time Constantine adopted the Hebrew weeks for official use in AD 321, altering the day of rest by declaring the Lord's day the Day of the Sun (dies Solis) a legal holiday. Different scholars have placed the end of 8-day markets at various dates from the late 1st to early 5th centuries.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#108

Post by Tor3 »

tomoyoirl wrote: post #36
throwaway211 wrote: post #4

Reading the article, I wandered into the difference of Old Style and New Style dates and what happened in 1752. From [1]: By the 18th century, the English legal year – used for legal, financial and other civil purposes – had for centuries begun on 25 March, or Lady Day.[13][i] Thus, for example, 24 March 1707 was immediately followed by 25 March 1708, while the day following 31 December 1708 was 1 January 1708, with…

The Romans also used the March-based year; that’s why February has fewer days and why October is literally the eighth month

September-October-November-December: 7-8-9-10

And July used to be Quintilis (5) and August was Sextilis (6), but then Julius Cesar and Emperor Augustus came.. and got their own month names.

Re: Lewis Carroll – computing the day of the week for any given date (1887)

#109

Post by 8bitsrule »

aidenn0 wrote: post #91
8bitsrule wrote: post #90

Earlier quoted context omitted.

Hmmm. When I heard that joke long ago, the driver said it was the pluperfect subjunctive. And here I took his word for it.

Same thing. From Wikipedia: "The pluperfect (shortening of plusquamperfect), usually called past perfect in English"

Another especially funny part of that joke for me is that this is set in Boston (which has a couple of important colleges) ... because someone once told me that a lot of post-graduates of that college I was attending were driving taxicabs in that city.
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