Archive for the ‘Reference’ Category

When did linking begin?

Monday, July 28th, 2014

When did linking begin? by Bob DuCharme.

Bob republished an old tilt at a windmill that attempts to claim “linking” as beginning in the 12th century CE.

It’s an interesting read but I disagree with his dismissal of quoting of a work as a form of linking. Bob says:

Quoting of one work by another was certainly around long before the twelfth century, but if an author doesn’t identify an address for his source, his reference can’t be traversed, so it’s not really a link. Before the twelfth century, religious works had a long tradition of quoting and discussing other works, but in many traditions (for example, Islam, Theravada Buddhism, and Vedic Hinduism) memorization of complete religious works was so common that telling someone where to look within a work was unnecessary. If one Muslim scholar said to another “In the words of the Prophet…” he didn’t need to name the sura of the Qur’an that the quoted words came from; he could assume that his listener already knew. Describing such allusions as “links” adds heft to claims that linking is thousands of years old, but a link that doesn’t provide an address for its destination can’t be traversed, and a link that can’t be traversed isn’t much of a link. And, such claims diminish the tremendous achievements of the 12th-century scholars who developed new techniques to navigate the accumulating amounts of recorded information they were studying. (emphasis added)

Bob’s error is too narrow a view of the term “address.” Quoted text of the Hebrew Bible acts as an “address,” assuming you are familiar enough with the text. The same is true for the examples of the Qur’an and Vedic Hinduism. It is as certain and precise as a chapter and verse reference, but it does require a degree of knowledge of the text in question.

That does not take anything away from 12th century scholars who created addresses that did not require as much knowledge of the underlying text. Faced with more and more information, their inventions assisted in navigating texts with a new type of address, one that could be used by anyone.

Taking a broader view of addressing creates a continuum of addressing that encompasses web-based linking. Rather than using separate systems of physical addresses to locate information in books, users now have electronic addresses that can deliver them to particular locations in a work.

Here is my continuum of linking:

Linking Requires
Quoting Memorized Text
Reference System Copy of Text
WWW Hyperlink Access to Text

The question to ask about Bob’s point about quoting “…his reference can’t be traversed…” is, “Who can’t traverse that link?” Anyone who has memorized the text can quite easily.

Oh, people who have not memorized the text cannot traverse the link. And? If I don’t have access to the WWW, I can’t traverse hyperlinks. Does that make them any less links?

Or does it mean I haven’t met the conditions for exercising the link?

Instead of diminishing the work of 12th century scholars, recognizing prior linking practices allows us to explore what changed and for who as a result of their “…tremendous achievements….”

Government Shutdown = Free Oxford Content!

Thursday, October 10th, 2013

Free access to Oxford content during the government shutdown

From the post:

The current shutdown in Washington is limiting the access that scholars and researchers have to vital materials. To that end, we have opened up access for the next two weeks to three of our online resources: Oxford Reference, American National Biography Online, and the US Census demographics website, Social Explorer.

  • Oxford Reference is the home of Oxford’s quality reference publishing, bringing together over 2 million entries from subject reference, language, and quotations dictionaries, many of which are illustrated, into a single cross-searchable resource. Start your journey by logging in using username: tryoxfordreference and password: govshutdown
  • American National Biography Online provides articles that trace a person’s life through the sequence of significant events as they occurred from birth to death offering portraits of more than 18,700 men and women— from all eras and walks of life—whose lives have shaped the nation. To explore, simply log in using username: tryanb and password: govshutdown
  • Social Explorer provides quick and easy access to current and historical census data and demographic information. It lets users create maps and reports to illustrate, analyze, and understand demography and social change. In addition to its comprehensive data resources, Social Explorer offers features and tools to meet the needs of demography experts and novices alike. For access to Social Explorer, email online for a username and password.

An example of:

It’s an ill wind that blows nobody good

Whatever your political persuasion, a great opportunity to experience first class reference materials.

It’s only for two weeks so pass this onto your friends and colleagues!

PS: From a purely topic map standpoint, the site is also instructive as a general UI.

Referential transparency

Saturday, February 11th, 2012

Referential transparency

Robert Harper writes:

After reading some of the comments on my Words Matter post, I realized that it might be worthwhile to clarify the treatment of references in PFPL. Most people are surprised to learn that I have separated the concept of a reference from the concept of mutable storage. I realize that my treatment is not standard, but I consider that one thing I learned in writing the book is how to do formulate references so that the concept of a reference is divorced from the thing to which it refers. Doing so allows for a nicely uniform account of references arising in many disparate situations, and is the basis for, among other things, a non-standard, but I think clearer, treatment of communication in process calculi.

It’s not feasible for me to reproduce the entire story here in a short post, so I will confine myself to a few remarks that will perhaps serve as encouragement to read the full story in PFPL.

There is, first of all, a general concept of a symbol, or name, on which much of the development builds. Perhaps the most important thing to realize about symbols in my account is that symbols are not forms of value. They are, rather, a indices for an infinite, open-ended (expansible) family of operators for forming expressions. For example, when one introduces a symbol a as the name of an assignable, what one is doing is introducing two new operators, get[a] and set[a], for getting and setting the contents of that assignable. Similarly, when one introduces a symbol a to be used as a channel name, then one is introducing operators send[a] and receive[a] that act on the channel named a. The point is that these operators interpret the symbol; for example, in the case of mutable state, the get[a] and set[a] operators are what make it be state, as opposed to some other use of the symbol a as an index for some other operator. There is no requirement that the state be formulated using “cells”; one could as well use the framework of algebraic effects pioneered by Plotkin and Power to give a dynamics to these operators. For present purposes I don’t care about how the dynamics is formulated; I only care about the laws that it obeys (this is the essence of the Plotkin/Power approach as I understand it).


Finally, let me mention that the critical property of symbols is that they admit disequality. Two different assignables, say a and b, can never, under any execution scenario, be aliases for one another. An assignment to one will never affect the content of the other. Aliasing is a property of references, because two references, say bound to variables x and y, may refer to the same underlying assignable, but two different assignables can never be aliases for one another. This is why “assignment conversion” as it is called in Scheme is not in any way an adequate response to my plea for a change of terminology! Assignables and variables are different things, and references are yet different from those.

What do you think?

How would you apply this analysis to symbols/identifiers as used in topic maps?