On Wed, Apr 1, 2009 at 6:14 AM, Mike Taylor <[log in to unmask]> wrote:
> As usual, an ounce of example is worth a ton of exposition, so:
> Suppose I always keep a PDF of my latest paper at
> for the benefit of people who want to keep an eye on my research.
> (Hey, it might happen!) Today, I have a PDF there of a paper with the
> DOI 10.1111/j.1475-4983.2007.00728.x. Tomorrow, my new paper comes
> out, and I replace the old one with a PDF of that new paper whose DOI
> is 10.abcdefghij. I move the PDF of the old paper to
> Now, then -- the DOIs are identifiers: they are not in themsleves
> dereferencable (although of course they can be used as keys for some
> mechanism that knows how to dereference them). Each DOI always
> identifies the same Thing. The URLs are locations: they are
> dereferencable, but they do not give you any guarantee about what you
> will find at that location. Two different days, two different papers.
> Note that a single location (latest.pdf) contains at different times
> two different Things. And note that a single Thing (the older of the
> two papers) can be found at different times in two different
> locations. In contrast, the same identifier always identifies the
> same Thing, irrespective of what location it's at.
Hoorah for examples!
Assuming a world where you cannot de-reference this DOI what is it good for?