The day is panculturally recognized as a time reference, but many cultures are not concerned with the day as a uniform unit of duration. Instead, days can vary in length (like months and years), and it is not a problem.
Very few cultures have defined the concept of day both in relationship to a time reference and a uniform duration. The definition of a day in terms of multiples of smaller units of time, e.g., 86400 seconds, is culturally unique and extremely recent. In terms of human history, the definition of small units of time in relationship to solar cycles is also relatively recent. Previous to the pendulum, minutes and seconds were conceived as measures of angle in sidereal time. We are still in the process of working out the consequences of relating the precise measure of small durations to the cultural emphasis on the solar day. And it seems there is impatience about working through these consequences. Even within Europe, some communities rejected mean time in favor of canonical hours until the early 20th century. The Gregorian calendar reforms are still not globally accepted after over 400 years. Kevin Kevin K. Birth, Professor Department of Anthropology Queens College, City University of New York 65-30 Kissena Boulevard Flushing, NY 11367 telephone: 718/997-5518 "We may live longer but we may be subject to peculiar contagion and spiritual torpor or illiteracies of the imagination" --Wilson Harris "Tempus est mundi instabilis motus, rerumque labentium cursus." --Hrabanus Maurus Rob Seaman <[email protected]> Sent by: <[email protected]> 07/02/13 10:38 AM Please respond to Leap Second Discussion List <[email protected]> To Leap Second Discussion List <[email protected]> cc Subject [LEAPSECS] Calendars count days - clocks divide them up Warner Losh wrote: >> It is gratifying to see how flawlessly this standard is implemented, >> despite over 40 years of it being the standard. I guess the far older >> expectation that every minute has 60 seconds is kinda deeply engrained... > > Wikipedia drily notes that "Between 1000 (when al-Biruni used seconds) and > 1960 the second was defined as 1/86,400 of a mean solar day". That 1960 > endpoint to which it refers is the transition to the ephemeris second. > Rubber-seconds UTC, which has occasional minutes with !=60 seconds, > comes along in 1961. So we've got around 960 years of the second only > being a subdivision of the minute, versus 53 years or so of seconds > being more complicated than that. > > -zefram Standards aren't just randomly chosen, they express an underlying model of how the universe works. Implicit in the standards expressing, say, units of electric current and resistance are observations and inferences with names like "Ohm's Law". The proposed new formalism for the SI (metric) system relies on this explicitly: https://commons.wikimedia.org/wiki/File:Relations_between_new_SI_units_definitions.png http://nvlpubs.nist.gov/nistpubs/jres/116/6/V116.N06.A01.pdf The conceptual model underlying the SI-second is frequency. Civil timekeeping simply represents another standard. Conceptual models fail if an attempt is made to force fit them together. Speaking of frequency, consider the words that people use: http://www.wordfrequency.info/free.asp?s=y (This is American English - statistics for other languages would be welcome.) The ranks and frequencies of usage of words related to timekeeping: 54 year (n) 769254 90 day (n) 432773 188 week (n) 199268 237 month (n) 162685 273 hour (n) 138955 309 minute (n) 126660 683 second (n) 56022 The word "day" is used more than seven times as frequently as the word "second" (as a noun). The three calendar words (year/month/day) are more prevalent than the three clock words (hour/minute/second) by greater than four to one. Even "century" is used more frequently than "second", and "decade" is used almost as frequently: 606 century (n) 65667 731 decade (n) 53727 Whatever underlying model of human cognition, these data cannot be used to argue that our parsing of time into units of days is irrelevant to society. "Day" is more frequently used than key nouns like man, woman and child. The noun "second" is less frequently used than other words descriptive of days like morning and night - and the combined usage of the terms AM and PM is 50% more frequent than "second". In fact while all the words above are nouns the rankings are listed for all parts of speech. If you scroll down the very long list you will find that the top five most frequently used nouns themselves are: time year people way day People perceive time in a way that descends from a year and a day Rob _______________________________________________ LEAPSECS mailing list [email protected] http://six.pairlist.net/mailman/listinfo/leapsecs
_______________________________________________ LEAPSECS mailing list [email protected] http://six.pairlist.net/mailman/listinfo/leapsecs
