Issue 614: Definition of I4 Proposition Set and what an instance of I2 Belief is about

ID: 
614
Starting Date: 
2022-10-13
Working Group: 
3
Status: 
Open
Background: 

In the 54th CIDOC CRM & 47th FRBR/LRMoo SIG meeting, the SIG resolved to start a new issue dedicated to the redefinition of I4 Proposition Set. The issue stems from discussions on Issue 322. Martin Doerr & Christian-Emil Ore were tasked with shaping the scope of the issue. 

Some ideas:

  • An Attribute Assignment essentially talks about a single property instance, which forms a parallel to pointing to a named graph that contains one property instance. 
  • I1 Argumentation which results in an instance of I2 Belief cannot be a subclass of E13.
  • There is also a problem with S4 Observation if the reification construct deals with more than one property simultaneously (what is now referred to as Situation). 
  • The CRM set of properties that are equivalent to a named graph can be represented as a set of propositions and the connection between them in FOL. One can always name that and say that the predicate “X” stands for a proposition, in CRM an instance of E89. On the other hand, the scope note of I4 Proposition Set explicitly refers to binary propositions and formal ontology concepts, which seems too restrictive. Logical constructs does not specify the order or mode of the logical system the statements are expressed in. This could yield propositions that are incompatible with the CRM. The scope note needs redrafting.
  • The idea is that CRMinf can be connected to CRM compatible knowledge base through such statements. As CRMinf stands now, it seems that many things that we regard as premises and conclusions won’t be formulated in properties that have been defined in a formal ontology. In general, the scope of CRMinf should be broader than what can now be expressed. The reference to name graphs should explicitly only leave room for named graphs that contain 1+ property instances alone (rather than instances of properties and classes or just the one property instance permitted by E13). 
  • If there are any formalizations in FOL that can be used to declare the E13 reification of a single property as a specific case of a named graph, it would be interesting to look at it. 

Post by Martin Doerr (13 September 2023)

Dear All,

I suggest to discuss the meaning of I4 Proposition Set, also related to issue 550, 510, 610

Two problems:

  1.  the content model. If we follow the logic of P190, an I4 Proposition Set should be represented by a URI and a content model, which could be implemented as Named Graph in a KB. 
    If we take an I4 as a Propositional Object, we would still need a symbolic form, which would need a representative copy (or P190).
  2.  If we take an I4 as fitting  potentially the reality under discourse, or only as a "possible world" being discussed, we need to clarify this role. Using I2 Belief, we relate the Proposition Set to be "true" or "false".
    We need to clarify, if "true" means "real", if the propositions can be related to reality. Similarly, we need to clarify, if an I11 Situation, as a special case, is meant to be discussed as statements only, or, if "observed", to exist in reality.
    We need to interpret the link to an observation is implying its reality or not. This is particularly interesting if we observe an area and state it does NOT contain X. 
  3. We should clarify how we may refer to Proposition Sets with a human readable text, rather than a CRM compatible RDF model.

Best,

Martin

Current Proposal: 

Post by Martin Doerr (17 September 2023)

Dear All,

I made a mistake with the Issue number: The below message is actually a proposal for issue 614! So far, it has been formulated as:
 

"Some ideas:

  • An Attribute Assignment essentially talks about a single property instance, which forms a parallel to pointing to a named graph that contains one property instance. 
  • I1 Argumentation which results in an instance of I2 Belief cannot be a subclass of E13.
  • There is also a problem with S4 Observation if the reification construct deals with more than one property simultaneously (what is now referred to as Situation). 
  • The CRM set of properties that are equivalent to a named graph can be represented as a set of propositions and the connection between them in FOL. One can always name that and say that the predicate “X” stands for a proposition, in CRM an instance of E89. On the other hand, the scope note of I4 Proposition Set explicitly refers to binary propositions and formal ontology concepts, which seems too restrictive. Logical constructs do not specify the order or mode of the logical system the statements are expressed in. This could yield propositions that are incompatible with the CRM. The scope note needs redrafting.
  • The idea is that CRMinf can be connected to a CRM compatible knowledge base through such statements. As CRMinf stands now, it seems that many things that we regard as premises and conclusions won’t be formulated in properties that have been defined in a formal ontology. In general, the scope of CRMinf should be broader than what can now be expressed. The reference to name graphs should explicitly only leave room for named graphs that contain 1+ property instances only (rather than instances of properties and classes or just the one property instance permitted by E13). 
  • If there is any formalization in FOL that can be used to declare the E13 reification of a single property as a specific case of a named graph, it would be interesting to look at it. "

I hence reformulate:

  1. We need a connection of an I4 Proposition Set (represented in a KB via a URI) to a content model.
  2. If we follow the logic of P190, we can connect the proposition set to a materialized copy of an information object. The latter, in contrast to P190, will not be interpreted as representing an immaterial symbolic form of a certain symbolic level, but as representing an immaterial propositional form (see examples for E89 Propositional Object). This requires the latter to be either a set of statements in a KR language, OR in sufficiently unambiguous textual form (in the context and for the purpose of reference).
  3. We need 3 kinds of links: To E52 String, to a symbolic object, and to an external file, be it in RDF or clear text.
  • I propose "Jxx1,2,3 has model representation (represents model of): E52 String / E73 Information Object / E24 Human-Made Feature 
    • Jxx2 would be used for KR file contents, but also unambiguous texts, (P2 has type, such as “the Nebra Sky Disc dates to the Early Bronze Age” (Pernicka et al. 2020)"). Ontologically, the  "{}" connecting a URI in TRIG with a Named Graph corresponds to the Jxx2 link.
    • Jxx3 may point to a URL or archival identifier. Jxx3 is a shortcut of Jxx2 - Pxxx has representative copy.

An instance of I4 Proposition Set should be regarded to be neutral to the relationship to reality, as any Information Object. The relationship to reality is determined by the link using the proposition set: 

  1. In the context of I2 Belief, the belief value of "TRUE" means "real", if the propositions can be related to reality (i.e., are about real world items). "FALSE" means at least one of the propositions in the set are regarded to be not real. NOTE that in a set of inconsistent propositions, the false one may not be known! Belief values expressing possibility or probability mean "possibly real" if the propositions can be related to reality.
  2. In the context of observable situations, the link between the observation activity and the situation implies the degree of reality assumed. It makes sense to observe that a situation did not hold (in its specified area and time).
  3. Only proposition set held to be true by the maintainers of a KB can be introduced as Named Graphs, because they become part of the stated knowledge.
  4. Proposition Sets held to be possibly true by the maintainers of a KB can be introduced as Named Graphs, if the operation of the KB foresees filtering by provenance and likelihood. In this case, Named Graphs are  particularly effective.
  5. implementation rule/ constraints for typing Named Graph URIs are required.
  6. Finally, observing or assigning a single property (E13) can be described as a shortcut to a content model held to be true....

I propose to decide, if this is the way to go forward, and then

  • Spell out the properties
  • Adjust scope notes of I4, Observation etc.
  • write the FOL connection between single property assignment and I4.

Best,

Martin

In the 57th CIDOC CRM & 50th FRBR/LRMoo SIG Meeting, MD walked the SIG through a proposal on how to connect an I4 Proposition Set to a content model. 
His proposal involved the following: 

  • Introduce a set of properties pointing from I4 Proposition Set to E62 String, E73 Information Object, E25 Human-Made Feature and provide their definitions. 
  • Define the relationship of an I4 to reality through I2 Belief. 
  • Define E13, which forms a single property assignment, as a specific case of I4 Proposition Set through FOL. 
  • Define S4, which forms a single observation, as a specific case of I11 Situation through FOL.
  • Adjust the scope notes for I4, S4

Discussion points:

  • Concerning the relation to reality: the KB should allow one to express statements that were previously considered to be true, but are now considered to be false by its maintainers, as this allows one to observe the evolution of the statements within the KB. The alternative of creating snapshots of the KB (instances of E73) and linking to them through the content model is OK, but should not be the only choice. 
  • Content model seems a bit obscure as a term. It needs to be properly defined. 

Decisions:
The SIG voted in favor of introducing a content model (analogous to P190) and discuss the I4 Proposition Set’s relationship to reality as sketched in MDs HW and provide the scope notes for the properties. 

HW: PF (to lead), MD, GH, AGr, & SdS (to proofread).
 

Reference to Issues: