Re: [xml-dev] markup humility

[Michael Kay <mike@saxonica.com>]

> 
> My other favourite example is that http://dbpedia.org/resource/Jordan_River is the River Jordan, whereas http://sws.geonames.org/7874114/ is the River Jordan (that part of it which is in Jordan).  Whether those are equivalent things or not is a question which requires lots of context (cultural and political, on top of the geographical and hydrographical), and which very much depends on a client application.
> 

Geographical entities are a great example of things with fuzzy identity. At one level, if you refer to London, England, the reference is completely clear and unambiguous. At another level, there are many different geographical areas and administrative units that you might be referring to, and all of them change over time. If that's true of cities, then it's even more true of rivers and mountains.

Reality is hopelessly complicated. All we can ever do is build models of reality, in which we abstract the complications away. If you're planning to attend a conference in London, England, then you really don't care about the fine distinctions of what London is. But if you want to brag about how many Munro's (Scottish mountains) you have climbed, then you need to pay careful attention to the rules that decide when something is one mountain and when it is two.

The distinction between metaphysics and information engineering is that in information engineering we are building models, and the models don't have to be correct, they only have to be useful.

Michael Kay
Saxonica