# Re: Review Direct Semantics

From: Thomas Schneider <schneidt@cs.man.ac.uk>
Date: Mon, 6 Apr 2009 13:00:27 +0100
Message-Id: <0AE8B8EB-545C-4784-AEF2-8B42C467576F@cs.man.ac.uk>
To: OWL Working Group WG <public-owl-wg@w3.org>
Hi Boris,

On 6 Apr 2009, at 12:48, Boris Motik wrote:

> Hello,
>
> [snip]
>
> Fair enough -- I've changed the definition of the model to be
> datatype map. I haven't, however, changed the last sentence in
> Section 2.5: this
> sentence is meant to be explanatory and it seems to me that adding a
> bunch of
> "w.r.t. D" and "for D" would just make it harder to understand.

Thanks, that's exactly how I had it in mind.

>> [snip]
>>>> * Throughout
>>>>
>>>> - When viewing the document with sans-serif fonts, the capital
>>>>   letter I and the digit 1 can hardly be distinguished. This
>>>>   complicates reading some of the expressions used in the document,
>>>>   e.g. those in the 3rd and 4th line of Table 4. In 2.4, you even
>>>>   use I_1, which contains \Delta_I and \cdot^{I_1}, but all
>>>>   subscripts read like the capital I.
>>>>
>>>>   I remember that Boris has mentioned this problem in the last
>>>>   discussion, but I don't think we've fully discussed the
>>>>   alternatives here. I'm aware that possible changes can be
>>>>   far-reaching and therefore require a lot of work, but still I'd
>>>>   prefer to avoid confusion whenever possible. So how about using
>>>>   the capital "J" instead of "I"?
>>>>
>>>
>>> I've changed I into J in the definition of models. (I believe the
>>> latter was the
>>> only place where we used {I_1}.)
>>
>> Thanks, that's better.
>>
>>> The changed text looks again quiet ugly, but there is nothing I can
>>> do here:
>>> HTML is just completely inadequate for typesetting mathematics and
>>> we will just
>>> have to live with this ugliness.
>>
>> (1) I agree that the maths will always look ugly.
>>
>> (2) But I don't think we have to live with the addressed ambiguity.
>> My
>> suggestion was actually to replace I with J *globally*, which could
>> avoid confusion at least between the capital letter I and the digit 1
>> used in super-/subscripts. I'm aware that this change (a) doesn't
>> make
>> the maths nicer (which just confirms theorem (1) ;-)), and (b) can
>> have far-reaching consequences. But it might make reading easier,
>> which I find a justifiable motivation. As for (b), I can offer help
>> with the necessary changes.
>>
>
> But now there aren't any I_1 in the document, so there is no need to
> change
> anything and we should be fine, right? I'm not convinced that
> changing the
> remaining Is into Js is necessary (and/or desired).

Well, I actually had expressions like (a_1)^I in mind, which occur
quite often. But re-considering my suggestion, I'm not convinced of
its usefulness anymore.

So thanks for the discussion.

Cheers

Thomas

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|  Dr Thomas Schneider                         schneider@cs.man.ac.uk  |
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