Re: Objects and Relations
From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Wed, 07 Feb 2007 21:37:14 GMT
Message-ID: <eEryh.3709$R71.56071_at_ursa-nb00s0.nbnet.nb.ca>
>>On Feb 6, 11:04 pm, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>>
>>>On Feb 6, 12:54 pm, "David BL" <davi..._at_iinet.net.au> wrote:
>>>
>>>>On Feb 6, 7:26 pm, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>>>
>>>>>On Feb 6, 5:26 am, "David BL" <davi..._at_iinet.net.au> wrote:
>>>
>>>>>>On Feb 6, 12:29 am, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>>>
>>>>>>>On Feb 5, 1:25 pm, "David BL" <davi..._at_iinet.net.au> wrote:
>>>
>>>>>Discussion of OID's snipped because it appears we are in fact largely
>>>>>agreeing that all labels are attributes - and consequently that
>>>>>identity should not depend on a pointer or memory address, which is
>>>>>obviously not part of the real world data.
>>>
>>>>Good!
>>>
>>>>>>>>I agree that E/R modelling should be "consigned to being an
>>>>>>>>organizational tool", but again for different reasons. Unlike you I
>>>>>>>>see no problem with saying entities have identity.
>>>
>>>>>>>I have never said that. What I have argued is that they are identified
>>>>>>>by their attributes and not some imaginary hidden barcode.
>>>
>>>>>>I agree with that but don't see how that explains why E/R diagrams can
>>>>>>be problematic.
>>>
>>>>>This was an argument against OID's not E/R diagrams.
>>>
>>>>I hadn't realised you had a different argument against E/R diagrams.
>>>
>>>>>The argument against E/R diagrams is trying to define what an entity /
>>>>>is/. For example, if bob is married to shiela, is married_to a
>>>>>relationship or an entity? And if it is an associative entity, why are
>>>>>all relationships not then just entities? Or to put it a different way
>>>>>(and the way much of modern philosophy views knowledge) should all
>>>>>entities not just be viewed as n-ary relationships themselves? Once
>>>>>you arrive at this premise, by whatever route, whether it be data
>>>>>analysis, reductionism, etc, you are left with something that starts
>>>>>to look incredibly like NIAM/ORM, which in turn has a natural
>>>>>translation to relational modelling.
>>>
>>>>>>The claim that entities are illusionary or abstract
>>>>>>doesn't appeal to me.
>>>
>>>>>Fair enough. You are incorrect, but that would be a philosophical
>>>>>debate, and largely tangential to the practical issues at hand.
>>>>>However it is worth noting that your standpoint is that of
>>>>>essentialism, which carries little weight in modern epistimology.
>>>
>>>>My tendency these days is to believe that the universe (actually
>>>>multiverse) only exists in a Platonic sense and physical reality is a
>>>>kind of trick played on us as self-aware substructures of the
>>>>multiverse. That kind of kills the whole question of what is real
>>>>versus what is abstract. It seems more convenient to define
>>>>everything to be real (not abstract), whether they be humans or
>>>>numbers.
>>>
>>>>>So,
>>>>>perhaps instead you could clarify what you mean by an 'entity' and
>>>>>define exactly what it is, as a starter to convincing me that it is
>>>>>not in fact an abstract notion. (and please try and avoid using the
>>>>>word 'thing' in any such a definition).
>>>
>>>>Perhaps a more pertinent question is to ask you to define the
>>>>difference between real and abstract.
>>>
>>>>It's impossible to define entity in terms of simpler notions but I can
>>>>clarify my viewpoint.
>>>
>>>>If I point at a bunch of atoms and say "That is a human named Fred"
>>>>then I consider Fred to be conceptual, mathematically imprecise but
>>>>nevertheless the concept itself is real and exists in a Platonic sense
>>>>(to the extent that I can meaningfully make statements about that
>>>>bunch of atoms as I conceive of it as being a human named Fred).
>>>
>>>Well first pointing isn't allowed. One cannot continually follow Fred
>>>round pointing at him all day, we need to identify to him in some
>>>other way, but there I think we are agreed.
>>>
>>>However consider that some people's view of Fred is that Fred is Fred
>>>is Fred, throughout his whole lifetime. Other people/applications may
>>>need to view Fred only as he is /now/ - after all he will be composed
>>>of a completely different set of atoms in a few years anyway. Then
>>>there must be parts of him that make up our view of him which are
>>>purely abstract, his bravery, his humour, his IQ, his body of
>>>publications, etc., how should they perdure? Already the notion of
>>>where he starts and finishes as an 'entity' is seriously blurring.
>>
>>That's why I said the mathematical concept of Fred is imprecise and
>>can only be used meaningfully to the extent that we can state facts
>>about Fred and not be confused.
>>
>>If we could transplant body parts for example, then yes the
>>imprecision in the mathematical concept is exposed.
>>
>>
>>>The old washington's axe/theseus ship paradox is perhaps a better
>>>example of the concept of a well defined entity being insufficient. I
>>>am sure you know it - "In a museum somewhere there is the axe used by
>>>washington. Ok, the handles been changed a few times. Oh and so has
>>>the headstock, but hey... its still the same axe". Same 'axe entity',
>>>completely different physical components. Something seems intuitively
>>>wrong with this notion of an axe 'entity/object'.
>>
>>I feel it's worse if you're unwilling to say entities exist (even
>>imprecisely) in any objective sense at all.
>>
>>
>>>But this problem is not really a paradox at all if you just discard
>>>the illusion that an entity exists anywhere outside a single
>>>individuals head.
>>
>>I'm not entirely sure of your philosophy. Do you also say that more
>>precise mathematical notions like the set of integers only exist in an
>>individual's head?
>>
>>
>>>That's again why I believe one should always
>>>consider communicated propositions (which we have a shared common
>>>understanding of). Then you it becomes clear that the axe is the same
>>>axe if propositions discussing it use its name as the primary key. It
>>>is a different axe if the headstock/handle attributes are the compound
>>>key.
>>
>>I can't help but think it's a little ridiculous to state facts about
>>things and not believe those things exist in any objective sense. Do
>>you also believe that the facts don't exist either?
>>
>>This reminds me of the difference between realism and formalism. IMO
>>formalism without realism is a strange viewpoint.
>>
Date: Wed, 07 Feb 2007 21:37:14 GMT
Message-ID: <eEryh.3709$R71.56071_at_ursa-nb00s0.nbnet.nb.ca>
JOG wrote:
> David BL wrote: >
>>On Feb 6, 11:04 pm, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>>
>>>On Feb 6, 12:54 pm, "David BL" <davi..._at_iinet.net.au> wrote:
>>>
>>>>On Feb 6, 7:26 pm, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>>>
>>>>>On Feb 6, 5:26 am, "David BL" <davi..._at_iinet.net.au> wrote:
>>>
>>>>>>On Feb 6, 12:29 am, "JOG" <j..._at_cs.nott.ac.uk> wrote:
>>>
>>>>>>>On Feb 5, 1:25 pm, "David BL" <davi..._at_iinet.net.au> wrote:
>>>
>>>>>Discussion of OID's snipped because it appears we are in fact largely
>>>>>agreeing that all labels are attributes - and consequently that
>>>>>identity should not depend on a pointer or memory address, which is
>>>>>obviously not part of the real world data.
>>>
>>>>Good!
>>>
>>>>>>>>I agree that E/R modelling should be "consigned to being an
>>>>>>>>organizational tool", but again for different reasons. Unlike you I
>>>>>>>>see no problem with saying entities have identity.
>>>
>>>>>>>I have never said that. What I have argued is that they are identified
>>>>>>>by their attributes and not some imaginary hidden barcode.
>>>
>>>>>>I agree with that but don't see how that explains why E/R diagrams can
>>>>>>be problematic.
>>>
>>>>>This was an argument against OID's not E/R diagrams.
>>>
>>>>I hadn't realised you had a different argument against E/R diagrams.
>>>
>>>>>The argument against E/R diagrams is trying to define what an entity /
>>>>>is/. For example, if bob is married to shiela, is married_to a
>>>>>relationship or an entity? And if it is an associative entity, why are
>>>>>all relationships not then just entities? Or to put it a different way
>>>>>(and the way much of modern philosophy views knowledge) should all
>>>>>entities not just be viewed as n-ary relationships themselves? Once
>>>>>you arrive at this premise, by whatever route, whether it be data
>>>>>analysis, reductionism, etc, you are left with something that starts
>>>>>to look incredibly like NIAM/ORM, which in turn has a natural
>>>>>translation to relational modelling.
>>>
>>>>>>The claim that entities are illusionary or abstract
>>>>>>doesn't appeal to me.
>>>
>>>>>Fair enough. You are incorrect, but that would be a philosophical
>>>>>debate, and largely tangential to the practical issues at hand.
>>>>>However it is worth noting that your standpoint is that of
>>>>>essentialism, which carries little weight in modern epistimology.
>>>
>>>>My tendency these days is to believe that the universe (actually
>>>>multiverse) only exists in a Platonic sense and physical reality is a
>>>>kind of trick played on us as self-aware substructures of the
>>>>multiverse. That kind of kills the whole question of what is real
>>>>versus what is abstract. It seems more convenient to define
>>>>everything to be real (not abstract), whether they be humans or
>>>>numbers.
>>>
>>>>>So,
>>>>>perhaps instead you could clarify what you mean by an 'entity' and
>>>>>define exactly what it is, as a starter to convincing me that it is
>>>>>not in fact an abstract notion. (and please try and avoid using the
>>>>>word 'thing' in any such a definition).
>>>
>>>>Perhaps a more pertinent question is to ask you to define the
>>>>difference between real and abstract.
>>>
>>>>It's impossible to define entity in terms of simpler notions but I can
>>>>clarify my viewpoint.
>>>
>>>>If I point at a bunch of atoms and say "That is a human named Fred"
>>>>then I consider Fred to be conceptual, mathematically imprecise but
>>>>nevertheless the concept itself is real and exists in a Platonic sense
>>>>(to the extent that I can meaningfully make statements about that
>>>>bunch of atoms as I conceive of it as being a human named Fred).
>>>
>>>Well first pointing isn't allowed. One cannot continually follow Fred
>>>round pointing at him all day, we need to identify to him in some
>>>other way, but there I think we are agreed.
>>>
>>>However consider that some people's view of Fred is that Fred is Fred
>>>is Fred, throughout his whole lifetime. Other people/applications may
>>>need to view Fred only as he is /now/ - after all he will be composed
>>>of a completely different set of atoms in a few years anyway. Then
>>>there must be parts of him that make up our view of him which are
>>>purely abstract, his bravery, his humour, his IQ, his body of
>>>publications, etc., how should they perdure? Already the notion of
>>>where he starts and finishes as an 'entity' is seriously blurring.
>>
>>That's why I said the mathematical concept of Fred is imprecise and
>>can only be used meaningfully to the extent that we can state facts
>>about Fred and not be confused.
>>
>>If we could transplant body parts for example, then yes the
>>imprecision in the mathematical concept is exposed.
>>
>>
>>>The old washington's axe/theseus ship paradox is perhaps a better
>>>example of the concept of a well defined entity being insufficient. I
>>>am sure you know it - "In a museum somewhere there is the axe used by
>>>washington. Ok, the handles been changed a few times. Oh and so has
>>>the headstock, but hey... its still the same axe". Same 'axe entity',
>>>completely different physical components. Something seems intuitively
>>>wrong with this notion of an axe 'entity/object'.
>>
>>I feel it's worse if you're unwilling to say entities exist (even
>>imprecisely) in any objective sense at all.
>>
>>
>>>But this problem is not really a paradox at all if you just discard
>>>the illusion that an entity exists anywhere outside a single
>>>individuals head.
>>
>>I'm not entirely sure of your philosophy. Do you also say that more
>>precise mathematical notions like the set of integers only exist in an
>>individual's head?
>>
>>
>>>That's again why I believe one should always
>>>consider communicated propositions (which we have a shared common
>>>understanding of). Then you it becomes clear that the axe is the same
>>>axe if propositions discussing it use its name as the primary key. It
>>>is a different axe if the headstock/handle attributes are the compound
>>>key.
>>
>>I can't help but think it's a little ridiculous to state facts about
>>things and not believe those things exist in any objective sense. Do
>>you also believe that the facts don't exist either?
>>
>>This reminds me of the difference between realism and formalism. IMO
>>formalism without realism is a strange viewpoint.
>>
> > This thread should then now probably belong on a philosphy board, but > hey, its been interesting.
I have no doubt you found it interesting because you have been talking to yourself, Jim.
Try this experiment: Open a dictionary to a random word and write it
down. Open the dictionary to a completely different random word and
consider the ways the two words are related.
Your mind will find a connection because it is wired to do so. When
David posts nonsense, your mind refuses to accept that it has no sense
and forces some sensible meaning onto it. But that meaning comes from
your own mind.
It takes discipline to stick to the meaning of what is actually written.
I also highly recommend Gilovich's _How We Know What Isn't So_.
>>I note as well that Godel's theorems should not be interpreted as
>>favoring formalism over realism. On the contrary I see it as
>>revealing a limitation of formalism. In fact Godel himself was a
>>Platonist.
> > You have invoked Godel's law. This is the cdt equivalent of Godwin's > Law which states that as a usenet thread approaches infinity, the > chance of that thread mentioning Hitler becomes 1 (i.e. a certainty).
And you have given him the Godwin.
> It's generally agreed upon that when this happens, the thread is over, > and the person mentioning Nazis losing the discussion. > > Here it seems to be Godel ;)
Hey, that's unfair. I generally mention Goedel up front whenever I mention formalism just to acknowledge the limits of any formalism.
[remaining nonsense snipped] Received on Wed Feb 07 2007 - 22:37:14 CET