On Thu, 25 Nov 2010 17:00:50 +0100, Jakob Voss wrote

> Using the same argument I propose to replace all Date/Time Standards 
> by the following easy specification. There are three values:
> "now"
> "earlier"
> "later"

That's getting into the field of modal logic (in particular Tense Logic).

But keeping to date standards--- and connecting with a discussion on the SRW/U
WG-- we might want to figure out some means of expressing volatile dates and

- Now resp. Today
- This week
- This month
- This year
- Next 2 days
- Yesterday
- The past two weeks
- Two weeks ago
- In 10 days
- Last December
- Next December
etc. etc. etc.

Up until now I've just implemented these as "natural phrases". See:


Edward C. Zimmermann, NONMONOTONIC LAB
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