----- Original Message -----
From: "Bill Potts" <[EMAIL PROTECTED]>
To: "U.S. Metric Association" <[EMAIL PROTECTED]>
Sent: Thursday, 2004-01-01 15:51
Subject: [USMA:28075] RE: Calendar, date and
time
Not really true.
The exact moments of noon and midnight are ambiguous. The instant of midnight can equally be considered the end of one day
The exact moments of noon and midnight are ambiguous. The instant of midnight can equally be considered the end of one day
If midnight is the end of the day, then it
should be described as 12 pm by the am/pm notation.
or the beginning of another.
Then midnight would be correctly described
as 12 am.
ISO 8601 even permits midnight to be written as
24:00 where one is referring to the day just ended (although no clock would, in
fact, display 24:00).
Similarly, the exact instant of noon can be considered as ending the morning or beginning the afternoon.
Similarly, the exact instant of noon can be considered as ending the morning or beginning the afternoon.
Noon is the meridian and is neither am
nor pm. It can't be before nor can it be after nor can it be both.
It is neither. Thus the am/pm notation can not apply to
nonn.
That is why I never use 12 am or 12 pm, preferring the non-ambiguous 12 noon and 12 midnight. And that is why I overwhelmingly prefer the ISO 8601 standard.
Smart move
Please note that analog watches and clocks, although based on 12 hours, say nothing about am and pm, leaving interpretation up to the owner/user.
Please note that analog watches and clocks, although based on 12 hours, say nothing about am and pm, leaving interpretation up to the owner/user.
By the way, why is going from 12:00:00 am to 12:00:01 pm any stranger than going from 11:59:59 am to 12:00:00 pm? They're equally strange and both arbitrary.
Simple. 12:00:00 am is midnight. The next
moment after midnight is still part of AM time. 11:59:59 am is followed by
12:00:00 with no reference to am or pm. See explanation
above.
Bill Potts, CMS
Roseville, CA
http://metric1.org [SI Navigator]
Bill Potts, CMS
Roseville, CA
http://metric1.org [SI Navigator]
Euric
