Steven, Kate: 

   One very confusing choice made by BIBFRAME is in the use of the term Instance to describe the class "".  
 Apart from the problematic use of a broad term from a different field to label a new, bibliographic specific concept, the decision not to use an existing term and concept from cataloging makes it harder for subject matter experts to spot problems in the definition of the new concept.

The definition of the class is a "[r]esource reflecting an individual, material embodiment of the Work." (emphasis added). 

If some individual is an instance of, it is an instance of a description of something. Statements made about a such an individual are statements about the description, not about the thing described. 

The definition uses the term embodiment. In FRBR terminology, this embodiment is a relationship between a FRBR Expression and a FRBR Manifestation.  Since BIBFRAME combines FRBR Work with FRBR Expression , this suggests that the thing that a is a description of corresponds to a FRBR Manifestation.

The use of the phrase material embodiment appears to reflect the phrase physical embodiment in the definition of Manifestation FRBR documentation.  These phrases are somewhat confusing, as a FRBR Manifestation is not a physical or material thing;  it is a set (more specifically, an equivalence class) whose members are individual, physical FRBR Items. These Items share a prototypical set of  physical characteristics (typeface, etc), but are different physical objects. (The editors confirm that this is the intended reading) 

If the thing an instance of is a description of is a FRBR Manifestation, then it describes a set of Items, not an Item  (even if the set only has one member). 

Interpreting properties like (which is a relationship between two instances of , and which is defined as "Resource that is manifested in another physical carrier.")  is left as an exercise for the reader.  Etiology may be more helpful than Ontology. Answers may involve the number 776.


On Wed, Jan 14, 2015 at 11:57 AM, Bowers, Kate A. <[log in to unmask]> wrote:

Then it is critical to discussion to clearly talk about bf:thingies as “instances” rather than “resources” or to always refer to a “library resource” or an“rdf resource”.


I know it feels silly, but when context is essential to convey meaning, it’s essential to express it consistently!




Kate Bowers

Collections Services Archivist for Metadata, Systems, and Standards

Harvard University Archives

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From: Bibliographic Framework Transition Initiative Forum [mailto:[log in to unmask]] On Behalf Of Steven Folsom
Sent: Wednesday, January 14, 2015 11:50 AM

To: [log in to unmask]
Subject: Re: [BIBFRAME] Annotations in BibFrame




Resource has at least two meanings in this thread.

  • A library resource from the library collection.
  • An RDF resource… "Any IRI or literal denotes something in the world (the "universe of discourse"). These things are called resources. Anything can be a resource, including physical things, documents, abstract concepts, numbers and strings; the term is synonymous with "entity" as it is used in the RDF Semantics specification [RDF11-MT]. The resource denoted by an IRI is called its referent, and the resource denoted by a literal is called its literal value. Literals have datatypes that define the range of possible values, such as strings, numbers, and dates. Special kind of literals, language-tagged strings, denote plain-text strings in a natural language.” Taken from-


The way I read the BIBFRAME documentation is:

  • The bf:Instance is an RDF resource "reflecting an individual, material embodiment of the Work.” (a physical library resource, including digital resources made up of 1’s and 0’s).
  • The bf:heldItem is an RDF resource reflecting the abstract concept of “Item holdings information”.