"Basically, they explained how all the rest of civilization's actors can predict their behavior"
(Steve Newcomb)
"What differentiates an information professional from someone who simply uses the tools?"
(Kurt Cagle)
A professional's predictability (reliability) is based on his understanding of and dedication to the subject matter's laws and principles. So there must *exist* such a subject matter which is substantial enough to allow for the emergence of something that might be called laws and principles.
The role of XML when it comes to giving us the possibility of thinking and acting as professionals is significant. This may sound strange, but please consider the following position: XML is an information model, it is a technology based on an information model, it is a way of thinking educated by the predictability of what happens when we use the technology with understanding, because the meaning of its operations (e.g. an XPath expression, an XQuery node construction, an XSLT transformation) is defined in terms of basic laws and principles. An example of such a basic law is the axiomatic definition of a "value" as a sequence of items, where an item is fully expressible in terms of a well-defined set of properties.
So XML offers a *definition* of information, and a fundamental distinction between outward shape and content. XML makes information manageable in important ways by arranging it in a global space of locations (nodes), allowing for the identification and navigation of information in a unified way (in terms of URIs and qualified names). XML introduces the concept of expressions which are resolved to information (as defined by its information model, of course). This amounts to a peculiar way of thinking about information which appears to me as important to an Information Professional as calculus to an engineer. Not to be applied at all times, but present in his mind in a dual way - as a methodology and as a basic pattern of thought.
XML may educate us to think about information in a clearer and deeper way than commonly practised. By capturing the layer of items, their identity and their structural relationships with perfect clarity, we do not deny the necessity of other layers, like semantics and behaviour. It is a seperation of concerns: by dealing with the "item view" of information in a comprehensive way which is governed by laws and principles, we create new possibilities to deal with those other layers in a clearer, maturer and more focused way.
It is strange to consider that the majority of programmers have no thoughts about what information *is*. They concentrate on the tools with which to achieve effects - meet requirements etc. As a rule, they pay little attention to the very subject matter they are working with - information. This haziness may lead to inappropriate - unprofessional - approaches. As an example, think of the usual approach to logging: instead of creating structured information consisting of named items with agreed upon semantics (event="containerArrival", containerNumber="X.", bridgeLabel="Y" [syntax irrelevant]), they commonly generate messages like "container X arrived at bridge Y", for which they later hunt with a grep command, rather than an XPath
expression.
In my opinion, the concepts of nodes (= location + content) and path expressions (= navigation between nodes) are fundamental to IT, so fundamental that their understanding should be required from a person regarding himself as an IT professional. Of course, there are other fundamental principles (the key concepts of object orientation, of the relational data model, of RDF, etc. etc.). The recognition of an Information Professional probably requires an emerging set of key concepts which the candidate can be expected to master. Ignorance coated with hostility is about as unprofessional as you can get, and I feel the commonness of this attitude is an indicator how far away we still are
from anything that might be called a profession. My personal estimate is that presently >90% of what is said and written about XML falls into that category. And this includes, I am sorry to say, much which has been said on this mailing list. Just notice the frequent tone of hostility and disparagement.
So let me draw this conclusion. One aspect of how to approach the goal of a profession is a joint effort to understand deeply and identify genuine key concepts, principles and laws. Of course this is a long process, not a project. What counts is a spirit dedicated to understanding.
Hans-Juergen
