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Re: Revised CIF syntax guidelines

Hi James

I'm sorry for the delay in responding: too many distractions, but also
the need to mull over this rather carefully.

> It is not my intention to create an absolute code,

I take that for granted, but I still make the point that a written
code can attract argument directed to the wording rather than the
underlying spirit. Both approaches are workable - in my analogy of a
political constitution, both "British" and "American" models lead to
workable societies; both achieve ready consensus on obvious points of
principle or law; both struggle with what we might call "edge cases";
and neither judicial precedent not constitutional amendment is
guaranteed to achieve the "right" result in such edge cases. Of
course, if resident in Britain I abide by the unwritten constitution,
if in America I live according to the documents of the Founding
Fathers.

It seems that COMCIFS is broadly in favour of adopting a formal set
of principles (based on the assumption that silence yields consent),
and I don't wish to lobby against that - simply to point out it's not
the approach I would personally prefer.

>                                                    rather to create a
> framework for discussions and promote a certain prejudice in favour of
> the positions outlined in the guidelines. COMCIFS voting members
> still remain the final arbiters.

That's fine, and I don't take the word "prejudice" in any pejorative
sense (which it usually does have). If you use the rather similar word
"bias", though, you also become aware of the importance that
"weighting" will have - i.e. the amount of bias controlled by the
other assumptions, aspirations, intentions and downright
misunderstandings that people bring along as part of their individual
baggage.

> Moving on to the particular comments about points 1(i) and (ii), note
> that the phrase "domain level" is defined in the preamble to include
> DDL dictionaries.  Insofar as a particular DDL can be used across all
> domains, changes that do not satisfy all of the criteria in 1, but do
> satisfy 1(ii), would logically be implemented using DDL mechanisms (ie
> at the "domain level").  So, for example, while fancy syntax could be
> introduced to indicate more detail about the relationships among data
> items in a data file, which would certainly be broadly useful, this
> has been done at a DDL level instead. Does this adequately answer this
> aspect of your concerns, Brian?

No. Maybe this is a mis-reading, or a variant reading that others do
not agree with; but as I read the proposed draft, the decision that we
have made to extend the base CIF character set to Unicode would
contravene principle 1(i), because the desired behaviour *could* have
been achieved at a domain level, either by adoption of a suitable
\unnn ASCII encoding agreed at DDL or dictionary level; or possibly by
admitting UTF-8 and other multibyte encodings. [It's not clear to me
that the principles as couched prohibit such extensions at the domain
level.]

I do understand your concerns about a formulation that is 'permissive'
- by which I mean one that does not prohibit a certain course of action
for which there is an appropriate rationale - because it then becomes
difficult to stand in the way of other actions that do not have so
strong a rationale (hence the "permissive society").

Again, I am wholly in sympathy with your intention to "shelter the
syntax from unnecessary complexity" as you go on to exemplify in your
post. This is a restatement of Ockham's razor, which temperamentally
I would be happy to adopt as a single concise statement of what we're
trying to say. But it's still not an answer - what is "necessary" has
to be teased out in the most difficult of cases.

This is a matter of judgement - of fine judgement, at that. How I
would propose to move this forward without expending even more time on
it is as follows. I move that we vote on my proposal to amalgamate
items 1(i) and 1(ii) as a single item:

    (i) Implementation of the desired behavior by changes at the domain
   level is not feasible, or else such changes, while feasible,  would
   significantly reduce human readability; OR the change provides
   significant new functionality that is widely applicable to those
   scientific domains where CIF is used

(Same text I posted last time.) If you don't get a seconder within a
couple of days, say by Monday, we can drop the matter; I shall take
this as a sign that COMCIFS collectively judges your position to give
the more robust set of working principles. If there is a seconder, and
the motion is voted against, I would take that decision in the same way.

In either case, if a vote is then called on your original formulation,
I am likely to vote for it, inasmuch as an agreed statement will still
provide a useful referent against which to test future decisions.

Best wishes
Brian
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