decad
Enable an agent to recognise, verify and manage a decad as a group or series of exactly ten countable members under an explicit counting rule.
Bundle → Layer → Finding → Questions Filled
5 bundles · 9 layers · 13 findings · 24 questions
Decad sense and boundary Establish which meaning of decad is intended before applying a ten-member test.
Collective sense
Identify the reading that treats a decad as a group or series of ten.
Provisional registry interpretation
The collective reading has direct lexical support in [Wikidata](https://www.wikidata.org/wiki/Q135236590), but its correspondence to this registry id remains to be verified.
- Does the registry's originating record identify a group or series of ten? provenance
- What example would the registry curator accept as an instance of this entry? definition
Competing word senses
Separate collective cardinality from other meanings of the same word.
Sense-specific routing
[Collins](https://www.collinsdictionary.com/dictionary/english/decad) records numerical, musical and decade-variant senses; the collective interpretation must therefore be selected explicitly.
- Does this usage denote ten members, the number ten, a duration or a specialised musical structure? boundary
- Which neighbouring model should receive a usage whose defining condition is not collective membership? action
Ten-member counting Make the numerical test reproducible by declaring the counted unit and duplication rule.
Unit of membership
Specify what contributes one member.
One counted member
The proposed operationalisation requires a stable counting level before evaluating the total.
- Is one member an individual object, an occurrence, a position or an entire subgroup? definition
- Are containers or subgroups being counted alongside their contents, mixing counting levels? measurement
Distinctness and total
Apply the equivalence rule and determine whether the resulting count is ten.
Ten after equivalence
Qualification depends on ten countable members after resolving duplicates under the declared collection form.
- Which apparent members refer to the same entity, and should repeated occurrences count separately? measurement
- Does the resulting enumeration contain exactly ten qualifying members? measurement
- Would switching from occurrence counting to distinct-entity counting change the result? boundary
Ten as a whole Describe the grouping boundary and any ordering that makes these ten a particular collective.
Grouping boundary
Explain why these members are included in the candidate whole.
Specified ten
A proposed instance needs an explicit selection, enumeration or membership rule identifying the relevant ten.
- What rule or act of selection brings these ten members into one group? definition
- Which nearby or related items are excluded, and by what rule? boundary
Order and collective identity
Distinguish a set of ten from a particular ten-position sequence.
Same ten, different arrangement
The model should record whether permuting the ten members changes only presentation or changes the identity of the represented series.
- Does each member have a significant position in an ordered series of ten? definition
- Would reordering the same ten members produce a different instance under the adopted identity rule? boundary
Decad verification and change Assess evidence for ten-member status and determine how changes affect that status.
Evidence for ten
Separate the asserted total from a reproducible membership count.
Enumerated versus asserted ten
The proposed verification rule distinguishes an evidenced total of ten from a name, expected capacity or partial list.
- What inspected enumeration or observation supports the claim of ten members? provenance
- Is the list complete, or could missing or unexamined members change the total? measurement
- Should qualification remain unresolved because the evidence establishes only an intended count? action
Changes to the ten
Reassess count and collective identity after membership changes.
Count preservation and replacement
Adding or removing a counted member changes numerical qualification; replacing one may preserve ten-member status while changing collective identity.
- After the proposed change, will exactly ten members still qualify under the same counting rule? measurement
- Does replacing a member preserve this group's identity or create a new ten-member collective? boundary
- Should the agent update qualification, record a successor collective or retain only a historical decad label? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these check these first hold for the sense of decad this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these real-world use hold for the sense of decad this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these typical measurements hold for the sense of decad this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these failure modes and hazards hold for the sense of decad this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of decad this model covers, and on what evidence? provenance
Classifiers Filled
- Family
- Thing Registry
- Category
- Cross-cutting context
- Entry kind
- thing
- Plane
- XCT
- Domain
- XCT.QLT
- Other names and narrower kinds
- dectet
What it is Filled
A decad is a group or set of ten, with a historical philosophical use for the number ten understood as a complete whole in Pythagorean thought.
In scope
- Groups or series whose defining member count is exactly ten
- Rules determining what constitutes one counted member
- Membership evidence and verification of the ten-member total
- Distinctions between ten distinct entities, ten occurrences and ten occupied positions
- Conditions under which changes preserve or invalidate decad status
Out of scope
- The abstract number ten and its general arithmetic properties
- Calendar decades and other durations
- Logarithmic intervals spanning a factor of ten
- Musical decads whose identity requires particular relationships among notes
- Specific named religious, philosophical or literary collections and their substantive content
- Decimal notation and base-ten numeral systems
Why it exists Filled
Enable an agent to recognise, verify and manage a decad as a group or series of exactly ten countable members under an explicit counting rule.
Distinguishing features Filled
- A candidate must identify what is being grouped; the numeral 10 alone does not identify a decad.
- Exactly ten members must qualify under the declared counting rule; an approximate count or a capacity of ten is insufficient.
- Ten repeated occurrences may qualify as a series of ten occurrences, while failing a requirement for ten distinct entities.
- A tenfold ratio does not establish ten members and therefore does not establish a decad in this scope.
- A ten-member count establishes numerical qualification but does not establish the additional identity conditions of a specialised named decad.
What robots and AI may and may not do Filled
Must not
- Present numerological claims about the decad as scientific fact.
- Attribute doctrines to Pythagoras or his followers without sources.
- Confuse decad with decade when the meaning differs.
Only with a human decision
- Publishing interpretations of ancient philosophical texts as authoritative.
May
- Explain the term and its use in Pythagorean thought from reliable sources.
- Use the word decad correctly for a set of ten.
Moral aspects Filled
- Ancient ideas are easily distorted when quoted without sources.
- Number mysticism can be sold to people as guidance it cannot give.
Who is affected
- Students and readers
- Scholars of ancient philosophy
Owners Filled
Steward
Nobody owns it; it is a shared word and idea.
Links to other meta-models Filled
parent
- Q4025884 - registry parent class
- Q99527517 - registry parent class
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.decad
- Wikidata: Q2643280 (https://www.wikidata.org/wiki/Q2643280)
Direct properties not applicable Not applicable
- Counted unit: Entity, occurrence, position, subgroup or explicitly defined domain unit
- Verified member count: Nonnegative integer in declared counted units; unknown when evidence is insufficient
- Collection form: Unordered set, multiset or ordered series
- Member equivalence rule: Same entity, same occurrence, same position or a documented domain equivalence
- Membership boundary: Candidate whole linked to included members and an inclusion rule
- Qualification state: Verified ten, verified non-ten, unresolved
- Identity basis: Fixed membership, ordered membership or continuing group with replaceable members
Plane XCT: no invented physical properties.
Recognition not applicable Not applicable
Not applicable
A decad is an abstract grouping whose membership requires counting rather than distinctive visual features.
Capabilities and actions required Filled
- Enumerate proposed members and verify whether the count is exactly ten.
- Resolve duplicates according to the declared member equivalence rule.
- Compare two decads for equal count, shared members and collective identity.
- Construct a ten-member grouping from eligible candidates under a stated selection rule.
- Revalidate decad status after additions, removals, replacements or changes to the counting rule.
- Route calendar, logarithmic and specialised uses of the name to their appropriate neighbouring models.
Hazards and failure modes required Filled
- Duplicate or omitted members can invalidate the claimed count and propagate errors into records.
- Ambiguous counting rules can cause people or agents to group different sets under the same label.
- Confusing a decad with a period of ten years can produce incorrect interpretations of historical or descriptive text.
Standards and interfaces not applicable Not applicable
Not applicable
The general concept of a group of ten has no dedicated applicable standard, law or official classification.
Context of use required Filled
- A decad is used when ten members or objects are treated as a single group under an explicit counting rule.
- The term also appears in historical philosophy when discussing ten as a complete numerical whole.
- In cataloguing or analysis, it requires a clear definition of membership and of what counts as one member.
Sources Filled
- Wikidata item Q2643280: decad - identity and sense of the item
- Wikipedia (de): Dekade (Einheit) - general description of the item
Open questions
- Does the originating registry record confirm the collective sense represented by Wikidata Q135236590, or intend a numerical or specialised sense?
- Does an existing Vercy model already own ten-member collectives, requiring this registry entry to link to it?
- Should registry-level decad membership permit repeated occurrences, or require ten distinct entities?
- Which attested uses treat a decad as a continuing group with replaceable members rather than a fixed set or sequence?
- How should historically named decads with disputed, lost or additional members be linked to the strict ten-member concept?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q2643280/spec.json