[uf-discuss] Authoritative hCards [was RE: Canonical hCards (was: Search on CSS element)]

Joe Andrieu joe at andrieu.net
Tue Jan 23 18:46:35 PST 2007

Tantek Ç elik wrote
> On 1/23/07 3:51 PM, "Scott Reynen" <scott at randomchaos.com> wrote:
> > I think identifying pointers
> > to a canonical source of data is a broader problem, as copying and 
> > manipulating data between sites is a standard activity on the web.
> Agreed.  However I find that the specific types of data may 
> have specific canonicalization semantics that we should be 
> careful not to accidentally overlook (we may choose to later 
> overlook them explicitly in the interest of creating a 
> building block that can be used across formats, but that 
> should be an explicit decision, not an incidental one).
> > Any search engine is full of links back to canonical sources.
> Actually I find that most search engines are full of links back to
> *multiple* sources of often the same thing without any 
> semantic on canonicality presented or implied.
> > Trackbacks are links back to canonical sources.  Bloggers 
> quoting each 
> > other typically link back to canonical sources.  Pingerati 
> has three 
> > links back to canonical sources of what could be abbreviated hcards 
> > (fn only), and right under that is the same thing for events and 
> > reviews.  Can we expand the types of examples we're looking at?
> None of those examples given are actually "canonical" 
> sources, they're merely citations and quotations of sources 
> (for which we have existing HTML semantics for: <cite> <q 
> cite> <blockquote cite>.  The semantic of canonicality is not 
> necessarily implied, only that the content came from 
> somewhere else, not that that somewhere else is the best / 
> most representative (i.e. canonical) instance of that content.

I think we don't mean "canonical" here, and perhaps fixing that will
clarify a use case that distinguishes the opportunity.

Canonical means part of a canon, or of the form of the canon, especially
when used in the sense of converting a morphological entity into an
alternative form.  2007/06/05 and June 6, 2007 both represent the same
date, only one can be canonical for any given canon.  We tend to like
ISO as a canon around here.  Canonical forms are articularly useful when
sorting, comparing, or looking up things that could be presented in
alternative formats.

What I think is much more useful is /authoritative/ hCards.  Meaning
that this is the author's truth for this reference.  The authoritative
reference is the root source of the reference.  It is close to
definitive, but definitive assumes objectivity, whereas authoritative
retains the subjectivity of the author.

This sense of subjectivity is where hCards can play a huge role.  An
authoritative hCard is, in effect, making a claim that it /is/ the
authoritative source for this data. It is not objective truth, simply a
claim by the author.

A few two major things happen when you do this:
1. You enable an hCard author to semantically declare this hCard as
2. You could provide a link from a refering hCard to the authoritative
hCard for discovery of additional information that isn't appropriate for
the design or context of the "refering" hCard.

If an authoritative hCard URL is also a permalink, it could then become
a single point of updates and changes that can suitably propagate out to
the world, a la Linked In.  

Furthermore, if the authoritative representation is dated in some way,
one might be able to discern between out of date and current claims to
authority on a topic.  (However, I definitely don't regard assertions
about chronological superiority as valid means to disambiguate such
claims; this is definitly a "hypothetical").

And to skip a bunch of other hypotheticals out there, I think it also
doesn't really matter if there are multiple "authoritative" hCards out
there.  What's useful is allowing someone to distinguish a claim to
authority for an hCard (say on my website) that is knowably distinct
from simple refering hCards (say on http://projectvrm.org where I am a
contributor; examples follow.)  False or duplicate claims to authority
are red herrings. The real value is to say "this isn't authoritive; and
btw, you might go look over there."

So, I think there are two different uses here that actually require two
different solutions.
 (1) to be able to indicate a claim that an hCard is authoritative. 
 (2) to be able to link a "brief" hCard to a source that was considered
authoritative (or even just /more/ authoritative) at the time the brief
hCard was created, in order to provide potentially more up-to-date
and/or more detailed information.

For instance, I currently present my information on my business website
as the authoritative "business" hCard for me and as a result of this
conversation, I've linked to that from Project VRM using hCard

(1) my "authoritative" hCard

<div class="contact vcard">For inquiries:<br/>
 <div class="fn">Joe Andrieu</div>
 <a class="email"
href="mailto:joe at switchbook.com">joe at switchbook.com</a><br/></a>
 <div class="tel">+1 (805) 705-8651</div>
 <a class="url org" href="http://www.switchbook.com"><span
class="switch">Switch</span>Book Software</a>
 <div class="adr">
  <span class="street-address">2032-A Chapala St.</span>, <span
class="locality">Santa Barbara</span>, <span class="region">CA</span>
<span class="postal-code">93105</span>
 <br/>You may also want to check out my <a

(2) a reference to it where a full hCard is impractical:

It is in a wiki:

<span class="contact vcard"><span class="fn">Joe
Andrieu</span><nowiki>[</nowiki><span class="url
org">[http://www.switchbook.com/ @]</span></span><nowiki>]</nowiki>

Which generates:
<span class="contact vcard"><span class="fn">Joe Andrieu</span>[<span
class="url org"><a href="http://www.switchbook.com/" class="external
text" title="http://www.switchbook.com/"

And looks pretty much how I want:
Joe Andrieu [@]

With the @ sign the link to the "authoritative" hCard.

If we presume for the moment that http://www.switchbook.com is the
authoritative reference for my hCard in this context, then, I /think/
that addresses use case #2, above, correct? The URL class in the hcard
point to a "more authoritative" hCard, where I have far more information
than fit in the reference at Project VRM.

However, we still have no official way for me to indicate in the hCard
at http://www.switchbook.com that it is an authoritative reference.  

Unless we use the self-referencing URL trick to indicate
"authoritative", in which case the current example solves both (1) and
(2). In effect, citing oneself as the "more authoritative" hCard means
that /this/ hCard is the most authoritative available (at the time of
creating the hCard, to the best knowledge of the author, etc.).

Working through this leads me to think that an hCard that exists at its
self-referenced URI should be considered "authoritative."


p.s. I'd appreciate feedback on any errors in the above microformats. 

Joe Andrieu
joe at andrieu.net
+1 (805) 705-8651

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