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Re: owl:sameAs - Is it used in a right way?

From: David Booth <david@dbooth.org>
Date: Mon, 18 Mar 2013 18:31:36 -0400
Message-ID: <514795C8.1090809@dbooth.org>
To: Oliver Ruebenacker <curoli@gmail.com>
CC: Jim McCusker <mccusj@rpi.edu>, Jeremy J Carroll <jjc@syapse.com>, Umutcan ŞİMŞEK <s.umutcan@gmail.com>, Kingsley Idehen <kidehen@openlinksw.com>, w3c semweb HCLS <public-semweb-lifesci@w3.org>
On 03/18/2013 06:21 AM, Oliver Ruebenacker wrote:
>       Hello David,
>
> On Sun, Mar 17, 2013 at 9:52 PM, David Booth <david@dbooth.org> wrote:
>> On 03/17/2013 10:55 AM, Oliver Ruebenacker wrote:
>>>
>>>        Hello,
>>>
>>> On Sat, Mar 16, 2013 at 12:30 PM, David Booth <david@dbooth.org> wrote:
>>>>
>>>> You are in good company in thinking that a URI always denotes the same
>>>> resource, because that is a widespread misconception.  (I call it Myth #1
>>>> in
>>>> http://dbooth.org/2010/ambiguity/paper.html .)  But it simply is not true
>>>> in
>>>> the RDF semantics.
>>>> [...]
>>>> That is precisely why it is helpful to keep different perspectives in
>>>> different graphs, as Jeremy suggested.
>>>
>>>
>>>     That's a little bit like saying, since floating-point numbers are
>>> not perfectly precise, the 1.376 in my data may not be the same as the
>>> 1.376 in your data, and therefore the two values should be kept in
>>> separate spaces.
>>
>>
>> I don't follow what you mean.  A floating point number like 1.376 may be
>> used as an approximation of some real number, but it is exactly the same
>> floating point number in all RDF graphs.
>
>    I'm not talking about how RDF handles floating point numbers. I'm
> just using floating point numbers as an example to show how flawed
> your logic is. If your logic would hold, that URIs have no meaning
> without context, because they are only approximate, then by the same
> logic, it would follow that floating-point numbers have no meaning
> without context.

I'm sorry, but I still do not understand your point.  I have been 
talking very narrowly about existing RDF Semantics.  It sounds like you 
are talking much more broadly about context, but I don't know what you 
mean.  Clearly 1.376 has no meaning without context.  To interpret it it 
correctly, you need to know that it is supposed to represent a number, 
it is represented in base 10, etc.  It is completely meaningless without 
knowing how to interpret it.  What is the analogy that you are trying to 
illustrate?

David
Received on Monday, 18 March 2013 22:32:06 UTC

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