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Re: PROV-ISSUE-8: defining generation in terms of `IVPT of'

From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
Date: Sat, 11 Jun 2011 18:56:37 +0000
To: "Myers, Jim" <MYERSJ4@rpi.edu>
CC: "public-prov-wg@w3c.org" <public-prov-wg@w3c.org>
Message-ID: <EMEW3|fd6a8f99f3afbcd1280040292bbc378bn5AJv408L.Moreau|ecs.soton.ac.uk|48FEE062-B0A1-4D1A-838F-299061E4FF04@ecs.soton.ac.uk>


On 11 Jun 2011, at 17:18, "Myers, Jim" <MYERSJ4@rpi.edu> wrote:

> Sorry -  I'm still having trouble understanding your issue - is 'relationship' the IVP of T relationship?
> 

No, sorry the word relationship in the definition (relationship between process execution and X)

A call is a good idea.

Luc

> (Should we try to arrange a call rather than exchange emails to make progress?)
> 
> Jim
> 
> -----Original Message-----
> From: Luc Moreau [mailto:L.Moreau@ecs.soton.ac.uk]
> Sent: Sat 6/11/2011 2:00 AM
> To: Myers, Jim
> Cc: public-prov-wg@w3c.org
> Subject: Re: PROV-ISSUE-8: defining generation in terms of `IVPT of'
> 
> Jim,
> 
> I had no concern. I wanted a clarification.
> - a point in time before which X does not exist, and after which it exists
> - a point in time within the duration of a process execution
> That's clear.
> 
> I don't think the word relationship conveys this meaning of a transition/event/action though.
> 
> Professor Luc Moreau
> Electronics and Computer Science
> University of Southampton
> Southampton SO17 1BJ
> United Kingdom
> 
> On 11 Jun 2011, at 03:56, "Myers, Jim" <MYERSJ4@rpi.edu> wrote:
> 
>> Luc,
>> I must be missing something = something is being generated/created by a process and you don't think that the sequence
>> Process start before X creation date before process ends is correct? If I'm phrasing it right, I think this is just the same set of constraints as in OPM for artifacts generated by a process.
>> 
>> Would your concern be different if I said X is an IVPT as you are defining them? (I'd say X has an IVPT relation to Y but X would still be something like a cake that appears to derive from things that are clearly not cake-like/other states of cake).
>> 
>> -- Jim
>> 
>> On 10 Jun 2011, at 21:02, "Myers, Jim" <MYERSJ4@rpi.edu> wrote:
>> 
>>>> 
>>>> In this definition, you say when X didn't exist(before P) but you
>>> don't say
>>>> when it starts to exist. Is it intended?
>>> 
>>> I updated the wiki as follows:
>>> * X did not exist before P began,
>>> * X began to exist sometime before P ended, and
>>> * X would not have begun existing if P had not occurred/P was necessary
>>> for X's existence to happen.
>> 
>> Doesn't this say X began to exist between the start and end of P?
>> 
>> Luc
>> 
>> 
>>> 
>>>> 
>>>> Also, did you really mean before P began? Can you explain why ?
>>> 
>>> If X is generated by P, it can't have existed before P did. I think this
>>> is just saying P must start before the creation of X if X is generated
>>> by P.
>>> 
>>> Is it a matter of wording or is something mixed up logically?
>>>> 
>>>> Can X change, i don't understand what happens then? Does the last
>>> condition
>>>> necessarily apply?
>>> 
>>> The generated thing/resource X can change after being generated, but
>>> only in ways consistent with its definition/type. An egg (defined as an
>>> ovoid object produced by a chicken) generated by a chicken can
>>> participate in boiling and painting (but I can't say what color such an
>>> egg is since color is not part of the definition of what makes one
>>> instance of the egg class unique/identifiable.) Other definitions of egg
>>> (IVPTs of each other) differ in how mutable they are. If you want a
>>> fairly immutable concept of egg, define it as a ovoid product of a
>>> chicken that has a particular color, is cooked/uncooked,
>>> cracked/uncracked, etc. Then we can talk about the Easter Egg that was
>>> derived from the uncooked/uncolored egg from a particular chicken
>>> through a series of processes. (Or, we could just say that after being
>>> generated, the egg sat and at some point we recognized that it existed
>>> in a state that corresponds to our notion of Easter egg and we assert
>>> that EasterEgg Y is an IVPT of egg X.)
>>> 
>>> Does the last condition apply? - Is that "must there always be a Y that
>>> X is an IVPT of"? I don't know, but I suspect the answer is yes in any
>>> practical sense. By the IVPT definition I posted, all I need is some
>>> process P that would destroy/consume X and define Y as "X considered
>>> mutable with respect to P" - "the idea of this egg that would be
>>> unaffected even by the end of the universe" or some such might be the
>>> end of the line though.
>>>> 
>>>> Are you also saying there needs to be another notion? Modification?
>>> 
>>> I think the other notion is some form of participation (also uploaded
>>> definitions there). I was saying participates in/is modified by for the
>>> thing/process relationship. (Agency/control would be one form of
>>> participation). The egg layed by the chicken participates in boiling and
>>> coloring during its lifetime. It is not modified in the sense that any
>>> part of what identifies it changes, but attributes of it we consider
>>> transient (can't be used to discover this egg reliably because they
>>> change) do change.
>>> 
>>> -- Jim
>>> 
>>> 
>>>> 
>>>> Professor Luc Moreau
>>>> Electronics and Computer Science
>>>> University of Southampton
>>>> Southampton SO17 1BJ
>>>> United Kingdom
>>>> 
>>>> On 10 Jun 2011, at 18:14, "Myers, Jim" <MYERSJ4@rpi.edu> wrote:
>>>> 
>>>>> Posted on the wiki - basically the same definition as from Jun and
>>>>> Daniel with more discussion of how the IVPT concept and the idea of
>>>>> modifiable objects relate.
>>>>> -- Jim
>>>>> 
>>>>>> -----Original Message-----
>>>>>> From: Luc Moreau [mailto:L.Moreau@ecs.soton.ac.uk]
>>>>>> Sent: Friday, June 10, 2011 12:57 PM
>>>>>> To: Myers, Jim
>>>>>> Cc: public-prov-wg@w3c.org
>>>>>> Subject: Re: PROV-ISSUE-8: defining generation in terms of `IVPT
>>> of'
>>>>>> 
>>>>>> Jim and all,
>>>>>> 
>>>>>> Could you put forward a revised definition that addresses better
>>> your
>>>>>> concerns?
>>>>>> 
>>>>>> Professor Luc Moreau
>>>>>> Electronics and Computer Science
>>>>>> University of Southampton
>>>>>> Southampton SO17 1BJ
>>>>>> United Kingdom
>>>>>> 
>>>>>> 
>>>>>> On 10 Jun 2011, at 17:51, "Myers, Jim" <MYERSJ4@rpi.edu> wrote:
>>>>>> 
>>>>>>> 
>>>>>>>> 
>>>>>>>> Hi Jim
>>>>>>>> I think we are discussing two issues here.
>>>>>>>> 
>>>>>>>> 1. You suggest that the egg is itself an IVPT.
>>>>>>>> 
>>>>>>>> There are different ways of looking at this:
>>>>>>>> a. I was saying that an egg was a thing (identified, and  typed
>>>>>>> according to
>>>>>>>> an ontology)
>>>>>>>>    Then, it's a question of choice of a same ontology, or
>>>>>>> ontology
>>>>>>>> refinement, a classical problem,
>>>>>>>>    which we will not solve here.
>>>>>>> 
>>>>>>> I would claim the things in IVPT relationships with egg are also
>>>>>>> things that can be identified, typed, etc., not necessarily in the
>>>>>>> same class or ontology as 'egg'. (A logical picture is not the
>>> same
>>>>>>> class of thing as a jpg file corresponding to a particular
>>>>>>> manifestation of that image).
>>>>>>> 
>>>>>>>> 
>>>>>>>> b. We could say that there is in an alternate account, which
>>>>>>> describes the
>>>>>>>> egg in terms of molecules.
>>>>>>> 
>>>>>>> Yes - my object in that account is 'set of molecules' and 'egg' is
>>> a
>>>>>>> convenient label for when those molecules are in a particular
>>> subset
>>>>>>> of all the configurations they can be in. If you say egg is an
>>>>> object
>>>>>>> and require a different type of thing to be used to describe
>>> things
>>>>>>> that invariant views of my set of molecules, I can't use it in my
>>>>>>> account, and we don't yet have any mechanism to make it clear that
>>>>>>> somehow my 'state of set of molecules' corresponds to your notion
>>> of
>>>>> 'egg'.
>>>>>>> 
>>>>>>>> 
>>>>>>>> c.  Alternatively, we have IVPTs of IVPTs of IVPTs ...
>>>>>>>>     is there a base case? I fear we are going to reach quantum
>>>>>>> mechanics ...
>>>>>>> 
>>>>>>> I don't think we have to be afraid of this - and I would rephrase
>>>>> and
>>>>>>> say we have things of different types that can be in IVPT
>>>>>>> relationships with each other and your concern is then whether the
>>>>>>> fact that we can make deep hierarchies is an issue. I'd answer
>>> that
>>>>> by
>>>>>>> saying that the base case is in the middle - things like eggs are
>>>>>>> useful not because they are somehow true objects where other
>>> things
>>>>>>> are just views, they are useful views because of the
>>> natural/common
>>>>>>> processes they participate in. The fact that the model allows one
>>> to
>>>>>>> describe a set of quantum wave functions and claim one view of
>>> them
>>>>> is
>>>>>>> an egg doesn't mean that this will happen in practice (though
>>> there
>>>>>>> are scientists who do essentially this on a daily basis at the
>>>>> nano-scale).
>>>>>>> 
>>>>>>> Whether it is truly 'turtles all the way down' is a philosophical
>>>>>>> question I'm not sure we have to answer - modeling it that way
>>>>> covers
>>>>>>> the middle ground without requiring any connection to real base
>>>>>>> objects (or more neutrally, without identifying a particular set
>>> of
>>>>>>> objects as real with all others some form of constructed view) -
>>> in
>>>>>>> this sense, I would ask you a) whether you see a
>>>>>>> consequence/limitation of a model that does not define which
>>> objects
>>>>>>> are 'real'? and b) given the debates about ontologies in the
>>> world,
>>>>> do
>>>>>>> you think we can reach a consensus on what the base reality is?
>>>>>>> 
>>>>>>> 
>>>>>>>> 
>>>>>>>> 2. You are commenting on the word modified.
>>>>>>>>  If I crack the egg,
>>>>>>>>    Y-> crack -> X
>>>>>>>>    Y and X are IVPTs of egg
>>>>>>>>    Y->X (we have a derivation)
>>>>>>>> 
>>>>>>>>  So looking at generation only, I feel it's OK to say the egg
>>>>> is
>>>>>>> modified, since
>>>>>>>> we
>>>>>>>> have now a new IVPT Y about the same egg.
>>>>>>>> 
>>>>>>>> So, could you maybe make some suggestions on how you would revise
>>>>> the
>>>>>>>> definition?
>>>>>>> 
>>>>>>> I'm not sure what point you're making about the cracking example,
>>>>> but
>>>>>>> I'd say generation is just a case where we are more
>>>>>>> familiar/comfortable with the thing produced by a process
>>> execution
>>>>> as
>>>>>>> a useful thing to discuss/track the provenance of, and potentially
>>>>>>> where the inputs of the process execution are uninteresting. A
>>>>> chicken
>>>>>>> lays an egg not because we can't talk about a set of atoms that
>>> the
>>>>>>> chicken rearranges into a state we want to identify as an egg but
>>>>>>> because that view is not very useful, so identifying the 'set of
>>>>> atoms
>>>>>>> in the chicken' that is used to produce the egg or the 'set of
>>>>> atoms'
>>>>>>> that exists before and after egg laying that comprise the egg
>>> after
>>>>>>> laying isn't useful and we record chicken controls eggLaying which
>>>>>>> generates egg. Both/all variant accounts are valid and consistent
>>> in
>>>>>>> the model I'm advocating, specifically egg does not change type
>>> from
>>>>>>> being a real object to a state of a set of atoms - 'set of atoms'
>>> is
>>>>> a
>>>>>>> real thing that has a stateful view corresponding to a real thing
>>>>>>> called an egg (an IVPT relation with egg). The fact that 99+% of
>>> us
>>>>>>> would just report generation of an egg and stop is OK (good in
>>> fact
>>>>> -
>>>>>>> we don't want to needlessly talk about alternate views any more
>>> than
>>>>>>> we should feel pressure to expand all processes into fine grained
>>>>>>> steps or include info about the movement of electrons in
>>> describing
>>>>>> computations).
>>>>>>> 
>>>>>>> Thanks,
>>>>>>> 
>>>>>>> Jim
>>>>>>>> 
>>>>>>>> Thanks,
>>>>>>>> Luc
>>>>>>>> 
>>>>>>>> 
>>>>>>>> On 06/10/2011 02:28 PM, Myers, Jim wrote:
>>>>>>>>> 
>>>>>>>>> 
>>>>>>>>>> -----Original Message-----
>>>>>>>>>> From: Luc Moreau [mailto:L.Moreau@ecs.soton.ac.uk]
>>>>>>>>>> Sent: Friday, June 10, 2011 3:26 AM
>>>>>>>>>> To: Myers, Jim
>>>>>>>>>> Cc: public-prov-wg@w3c.org
>>>>>>>>>> Subject: Re: PROV-ISSUE-8: defining generation in terms of
>>> `IVPT
>>>>>>> of'
>>>>>>>>>> 
>>>>>>>>>> Hi Jim,
>>>>>>>>>> 
>>>>>>>>>> I had not seen your comment in line, my responses are also
>>>>> inline.
>>>>>>>>>> 
>>>>>>>>>> On 10/06/11 02:28, Myers, Jim wrote:
>>>>>>>>>> 
>>>>>>>>>>> This would mean that a heating process modifies an egg to
>>> create
>>>>> a
>>>>>>>>>>> 
>>>>>>>>> warm egg,
>>>>>>>>> 
>>>>>>>>>> it does not transform a cold egg into a warm egg?
>>>>>>>>>> 
>>>>>>>>>>> Or do you mean both - a process execution can turn one thing
>>>>> into
>>>>>>>>>>> 
>>>>>>>>> another,
>>>>>>>>> 
>>>>>>>>>> these things can be considered IVPTs of a thing that
>>> participates
>>>>>>> in
>>>>>>>>>> 
>>>>>>>>> the process
>>>>>>>>> 
>>>>>>>>>> execution/ is modified by the process execution? And in an open
>>>>>>> world
>>>>>>>>>> assumption, a witness doesn't have to report the modified thing
>>>>> or
>>>>>>>>>> can
>>>>>>>>>> 
>>>>>>>>> decline
>>>>>>>>> 
>>>>>>>>>> to identify/report either of things in IVPT roles depending on
>>>>>>> their
>>>>>>>>>> 
>>>>>>>>> ability to
>>>>>>>>> 
>>>>>>>>>> observe and the use case they wish to enable?
>>>>>>>>>> 
>>>>>>>>>>> ________________________________
>>>>>>>>>>> 
>>>>>>>>>>> From: public-prov-wg-request@w3.org on behalf of Luc Moreau
>>>>>>>>>>> Sent: Thu 6/9/2011 6:44 PM
>>>>>>>>>>> To: Provenance Working Group WG
>>>>>>>>>>> Subject: PROV-ISSUE-8: defining generation in terms of `IVPT
>>> of'
>>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>>> Hi all,
>>>>>>>>>>> 
>>>>>>>>>>> - if a new thing is created, it is clear that we have a new
>>> IVPT
>>>>>>> of
>>>>>>>>>>> that thing
>>>>>>>>>>> 
>>>>>>>>>>> if a chicken creates an egg is it just an IVPT of an egg?
>>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>> I would think the physical object is the egg.
>>>>>>>>>> I thought we had agreed that for a provenance purpose, we had
>>> to
>>>>>>> talk
>>>>>>>>>> 
>>>>>>>>> about
>>>>>>>>> 
>>>>>>>>>> an IVPT of that egg.
>>>>>>>>>> 
>>>>>>>>> But 'the egg' is also an IVPT of the stuff that goes into the
>>> cake
>>>>> -
>>>>>>> a
>>>>>>>>> temporary 'state' in which yolk and white are together and not
>>>>>>>>> mixed/chemically altered, etc.
>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>>> - if the thing is modified, then it is a requirement that a
>>> new
>>>>>>> view
>>>>>>>>>>> 
>>>>>>>>> (IVPT) is
>>>>>>>>> 
>>>>>>>>>> generated ...
>>>>>>>>>> 
>>>>>>>>>>>     otherwise, it would still be a view that existed before
>>>>>>>>>>> 
>>>>>>>>>>> can't I say the egg was heated without reporting its cold and
>>>>> warm
>>>>>>>>>>> 
>>>>>>>>> states? I.e.
>>>>>>>>> 
>>>>>>>>>> don't we want to be able to report that something was modified
>>>>>>>>>> without
>>>>>>>>>> 
>>>>>>>>> having
>>>>>>>>> 
>>>>>>>>>> to report the IVPTs? A document was edited four times by
>>>>> different
>>>>>>>>>> 
>>>>>>>>> people but I
>>>>>>>>> 
>>>>>>>>>> don't wan't to/can't tell you what each wrote at each stage?
>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>> These comments were made in the context of defining Generation
>>> of
>>>>>>> an
>>>>>>>>>> 
>>>>>>>>> IVPT.
>>>>>>>>> 
>>>>>>>>> OK - but you said "if the thing is modified"... For generation,
>>> I
>>>>>>>>> would say the chicken participates in an egg laying process
>>>>>>> execution
>>>>>>>>> that generates an 'egg'. That 'egg' is an IVPT of the chemicals
>>> in
>>>>>>> it
>>>>>>>>> (which existed before). The 'egg' can also have further/more
>>>>>>> stateful
>>>>>>>>> IVPTs that are more useful for discussing heating, cracking,
>>> etc.
>>>>>>> The
>>>>>>>>> sense in which generation is special is that it is a derivation
>>>>> from
>>>>>>>>> things we don't consider logically an aspect/IVPT of something
>>>>>>>>> greater. I.e. the 'mass of egg-bound chemicals' in the chicken
>>>>> just
>>>>>>>>> changes its state to become the 'egg', nothing really appears or
>>>>>>>>> disappears (conservation of mass and energy). Unless/until a
>>>>>>> scientist
>>>>>>>>> wants to look at the potential for different processing of
>>>>> chemicals
>>>>>>>>> going into the egg versus those used to build the chicken's own
>>>>>>> body,
>>>>>>>>> 'mass of egg-bound chemicals' isn't something we'd usually think
>>>>>>>>> about, but it's a valid perspective and consistent with the view
>>>>> of
>>>>>>> an
>>>>>>>>> egg being generated (both views can be drawn on the same graph
>>> in
>>>>>>> the
>>>>>>>> way I've been describing).
>>>>>>>>> 
>>>>>>>>> 
>>>>>>>>>> The document was edited four times could be expressed by 4
>>>>> process
>>>>>>>>>> 
>>>>>>>>> execution
>>>>>>>>> 
>>>>>>>>>> and something like opm:wasTriggeredBy in between.
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>>> - if the process execution was taking a long time to
>>>>> modify/create
>>>>>>>>>>> 
>>>>>>>>> the thing,
>>>>>>>>> 
>>>>>>>>>> there is only one
>>>>>>>>>> 
>>>>>>>>>>> instant at which the (invariant!) IVPT appears
>>>>>>>>>>> 
>>>>>>>>>>> I thnk we could define it that way, but if a cracking process
>>>>>>> takes
>>>>>>>>>>> 
>>>>>>>>> time, saying
>>>>>>>>> 
>>>>>>>>>> the cracked egg appears instantaneously basically means you
>>> want
>>>>>>>>>> 
>>>>>>>>> 'cracked egg'
>>>>>>>>> 
>>>>>>>>>> to be defined by some threshold - the cracked egg might become
>>>>> more
>>>>>>>>>> 
>>>>>>>>> cracked
>>>>>>>>> 
>>>>>>>>>> over time ) invariant only in that it is always above the
>>>>> threshold
>>>>>>>>>> 
>>>>>>>>> and the
>>>>>>>>> 
>>>>>>>>>> instance of the creation of the IVPT relationship occurs ata
>>>>>>>>>> 
>>>>>>>>> aspecific instant.
>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>> Yes, agreed.
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>>>> - I think this captures well a stateful objects, where
>>> processes
>>>>>>> can
>>>>>>>>>>> 
>>>>>>>>> modify the
>>>>>>>>> 
>>>>>>>>>> object, resulting in
>>>>>>>>>> 
>>>>>>>>>>> different IVPTs corresponding to the various states
>>>>>>>>>>> 
>>>>>>>>>>> IVPTs are not a separate kind of thing and their invariance is
>>>>>>>>>>> 
>>>>>>>>> relative. If they
>>>>>>>>> 
>>>>>>>>>> are truly immutable sates/snapshopts, they can only exist for
>>> an
>>>>>>>>>> 
>>>>>>>>> instant because
>>>>>>>>> 
>>>>>>>>>> some part of the state of the thing (a part we may not care
>>> about
>>>>>>>>>> such
>>>>>>>>>> 
>>>>>>>>> as age)
>>>>>>>>> 
>>>>>>>>>> will change immediately.
>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>> I am not sure I agree, here. IVPTs are a view/perspective on a
>>>>>>> thing.
>>>>>>>>>> 
>>>>>>>>> Perhaps I should argue from the other direction - the notion of
>>> a
>>>>>>>>> thing is also a perspective/view. "eggs" don't exist - only
>>>>>>> temporary
>>>>>>>>> co-locations of particular molecules. Galton and Mizoguchi's
>>> paper
>>>>>>>>> argues that objects are defined by what processes you consider
>>> to
>>>>> be
>>>>>>>>> internal to and external to the object - if you change the set
>>> of
>>>>>>>>> processes you are concerned about, you describe the world using
>>>>>>>>> different objects. In this sense, eggs feel more 'real' because
>>>>> the
>>>>>>>>> set of processes we see happening frequently to them preserve
>>>>>>> aspects
>>>>>>>>> of their state, so egg as an IVPT is useful/predictive/etc.
>>>>>>>>> 
>>>>>>>>>> Alternative views asserted by other asserters may co-exit.
>>>>>>>>>> - it's a decaying egg
>>>>>>>>>> - it's a duck egg, not a hen egg
>>>>>>>>>> - it's a chocolate egg
>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>>> I agree, so again from the other direction - I don't see why
>>> 'egg'
>>>>>>> is
>>>>>>>>> more real/more correct/more special than any of these, they're
>>> all
>>>>>>>>> IVPTs.
>>>>>>>>> 
>>>>>>>>> 
>>>>>>>>>> It is a requirement of any specific perspective to be
>>> invariant.
>>>>>>>>>> 
>>>>>>>>> Invariant relative to a view in which only certain processes are
>>>>> of
>>>>>>>>> interest (are observable/reported?).
>>>>>>>>> 
>>>>>>>>> 
>>>>>>>>>> So, it's not a snapshot of the global egg state, but it's a
>>>>>>> snapshot
>>>>>>>>>> 
>>>>>>>>> according to a
>>>>>>>>> 
>>>>>>>>>> view.
>>>>>>>>>> 
>>>>>>>>>> An analogy would be several cameras pointing to a same egg.
>>>>>>>>>> From one camera, the egg is still, no change occurring.
>>>>>>>>>> From the other, we see a crack appearing.
>>>>>>>>>> So one asserter can describe change in a physical object, while
>>>>>>>>>> 
>>>>>>>>> another does not
>>>>>>>>> 
>>>>>>>>>> describe any change.
>>>>>>>>>> But it's the same egg.
>>>>>>>>>> 
>>>>>>>>> Right - those are two views of something. But that something is
>>>>> just
>>>>>>>>> another view - one camera sees a soup of chemicals that are
>>>>> swirling
>>>>>>>>> and mixing (slowly for an egg) while another sees one thing (the
>>>>>>> egg).
>>>>>>>>> Both of these are just IVPTs too. The chemical view is mutable
>>> by
>>>>>>> more
>>>>>>>>> processes than the egg view, but it is more persistent (it lasts
>>>>>>>>> longer because we've defined it in a way that the processes that
>>>>> can
>>>>>>>>> create/destroy it are less frequent).
>>>>>>>>> 
>>>>>>>>> I know that thinking of everything as an IVPT is not necessarily
>>>>>>>>> intuitive, and that one can argue that it is just one way to
>>> model
>>>>>>> the
>>>>>>>>> world/a philosophy, but I think it is a model that has the right
>>>>>>>>> conceptual power to deal with the use cases we have (and the
>>>>> general
>>>>>>>>> set we can envision) while also being one that, in practice,
>>> will
>>>>>>> fade
>>>>>>>>> away
>>>>>>>>> - most people will agree that 'egg' and not 'mass of chemicals'
>>> is
>>>>> a
>>>>>>>>> more useful IVPT to talk about and we'll see 'eggs' used in cake
>>>>>>>>> baking and the world will mostly look like OPM (straight
>>>>>>>>> thing-execution-thing chains), but we'll still have the power to
>>>>>>> drop
>>>>>>>>> down and talk about cracking or go up and talk about
>>> conservation
>>>>> of
>>>>>>> mass
>>>>>>>> when needed.
>>>>>>>>> 
>>>>>>>>> I also don't know what a coherent alternative is that, once we
>>> add
>>>>>>> in
>>>>>>>>> all the features necessary to cover the use cases, we'll like
>>>>>>> better.
>>>>>>>>> There are certainly other ways to model - my question really is
>>>>>>>>> whether there are others that will end up being more intuitive
>>>>> once
>>>>>>>>> all the needed features are dropped in.
>>>>>>>>> 
>>>>>>>>> -- Jim
>>>>>>>>> 
>>>>>>>>> Jim
>>>>>>>>> 
>>>>>>>>>> Luc
>>>>>>>>>> 
>>>>>>>>>>> What do you think?
>>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>> 
>>>>>>>> 
>>>>>> 
>>>> http://www.w3.org/2011/prov/wiki/ConceptGeneration#Definition_of_Gene
>>>>>>>>>> r
>>>>>>>>>> 
>>>>>>>>>>> ation_by_Luc
>>>>>>>>>>> 
>>>>>>>>>>> Cheers,
>>>>>>>>>>> Luc
>>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>> 
>>>>>>>> --
>>>>>>>> Professor Luc Moreau
>>>>>>>> Electronics and Computer Science   tel:   +44 23 8059 4487
>>>>>>>> University of Southampton          fax:   +44 23 8059 2865
>>>>>>>> Southampton SO17 1BJ               email:
>>> l.moreau@ecs.soton.ac.uk
>>>>>>>> United Kingdom
>>> http://www.ecs.soton.ac.uk/~lavm
>>>>>>> 
>> 
> 
Received on Saturday, 11 June 2011 18:57:31 GMT

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