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

From: Myers, Jim <MYERSJ4@rpi.edu>
Date: Fri, 10 Jun 2011 22:54:43 -0400
Message-ID: <B7376F3FB29F7E42A510EB5026D99EF2040413DA@troy-be-ex2.win.rpi.edu>
To: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
CC: <public-prov-wg@w3c.org>
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 02:56:52 GMT

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