This discussion seems rather shaky to me, because it seems to build too much
on weak foundations.

I maintain that, at the level at which it is of interest to us, there is no
coherent concept of a particular day/week/year/decade/century as an entity
in its own right, and that therefore there is no point (and that's on the
generous side) to elaborating this.

What does make common sense (and is therefore worth elaborating if possible)
(a) that an event happened within a given time interval, and for ease of
reference (only) the boundaries of that time interval may be aligned to
common chronological divisions
(b) that there is a set of events (constrained in some other way, as it is
impossible to catalogue all events in any time interval) that happened
within a certain time interval -- as (a), for convenience common boundaries
are often used. This may be what people have in mind when they refer to a
day, week, month, year, decade, century or whatever. I maintain it is the
only sense in which those time concepts can be meaningfully reified. Note,
however, that those with different calendars will be grouping together
different sets of things when they say, for instance, "that was a hard

There is nothing universal about any particular time interval. Why
prioritise a decade in a decimal calendar over some other interval of years
in some other calendar? The closer I consider things, the more arbitrary a
decade or a century appears. Hence my preference (and willingness to argue)
for a primary, general system of points and intervals, and only secondary
and less important (and only if trouble-free) some notations for selecting
ranges of years etc. etc.

The precisions mentioned here are fully dependent on the time system and
calendar, and therefore only "scientific" inasmuch as our current science
uses these units and this numbering system. I do *not* believe they are
worthy of standardization.


On 21 December 2010 19:37, Denenberg, Ray <[log in to unmask]> wrote:

> Rereading the recent (and not so recent) discussion I'm trying find a way
> to move this along, particularly the issue of precision. Ed seems to be the
> one most interested and he said:
> > At the heart of things I also don't want us to confuse dates with
> > intervals.
> > If I say something occurred in the 1960s I don't want to have to use
> > intervals
> > just as I don't have to use intervals to talk about 12 Sept 1933 (which
> > is
> > again saying something different from  1933-09-12T00:00Z/1933-09-
> > 12T23:59Z).
> >
> > I suggest we in generally have the following precisions:
> > - second
> > - minute
> > - hour
> > - day
> > - week
> > - month
> > - year
> > - decade
> > - century
> We have the precision Ed seeks for: second, minute, hour, day, week, month,
> and year.
> Which leaves decade and century.  Century is a separate discussion unto
> itself. I will treat that in a separate thread.
> So let's just talk about decade for the moment.
> Ed supports the 'x' approach: where we let 196x mean the decade, 1960s.
> There are reasonable arguments against this, but I'm willing to go along
> with it if it will move us forward. We're only talking about this for decade
> (and possibly century).
> Comments, please.
> --Ray

Simon Grant
+44 7710031657