"Infoman Inc." wrote on 2000-10-03 21:18 UTC:
"and on the seventh day, ye shall rest" for Gregorian calendar =Sunday, for Hebraic, Seventh Day Adventists (and others) = Saturday, etc.
On the other hand, in some languages (e.g., German: "Mittwoch"), the word for Wednesday means literally "middle of the week", which would imply a week-start of Sunday. Unfortunately, I have never seen a proper written rationale for the decision of ISO to declare in ISO 2015:1976 "Numbering of weeks" (withdrawn by TC154 on 1988-06-01 and now superseded by ISO 8601) that the week starts on Monday. Annex A of ISO 8601:1988 just says that before that, various week conventions were in use in various countries and that starting on Monday was considered to be the commercially most useful convention for selecting an international standard. Does anyone have a copy of ISO 2015:1976 that might contain a more detailed rationale? I do vaguely remember that I have read many years ago in a German publication for hobby astronomers a good article on the ISO week numbering standard. It said something along the lines that workers find it more convenient of weekly shift rotations start during the night from Sunday to Monday, because most people prefer to have a complete weekend before a shift change. Therefore, it seemed most compatible with industrial planning practice to start the new week on Monday as then shift rotations would correspond exactly to the week number. There were similar reasons for accounting practice in 24x7 operations and for the idea of making week 1 the first week with the majority of the days in the new year (to avoid pathologic partial weeks at the beginning and end of most years). The article also mentioned some protest by the churches in Germany, when around 1977 the DIN standard for calendar dates was changed to the new ISO convention and printed calendars started to show Monday as the first day of the week accordingly. Markus -- Markus G. Kuhn, Computer Laboratory, University of Cambridge, UK Email: mkuhn at acm.org, WWW: <http://www.cl.cam.ac.uk/~mgk25/>