necessity
Let an agent explain necessary conditions, identify the direction of implication between statements, distinguish necessity from sufficiency, and assess whether a claimed requirement follows from stated premises.
Bundle → Layer → Finding → Questions Filled
4 bundles · 8 layers · 8 findings · 16 questions
Sense Which necessity.
Which
Disambiguation.
Which
Disambiguation.
- Is logical, metaphysical, causal, practical or legal necessity meant? boundary
- Which entry or framework fits? action
Conditions
Necessary and sufficient.
Conditions
Conditions.
- Is this condition necessary, sufficient or both? definition
- How can the distinction be shown with examples? action
Logic Modal necessity.
Modal
Operators.
Modal
Modal operators.
- How are necessity and possibility formalised in modal logic? definition
- Which systems such as S4 and S5 apply? provenance
Metaphysics
Philosophical debates.
Metaphysics
Debates.
- What do philosophers say about metaphysical necessity and possible worlds? provenance
- Which positions are contested? boundary
Law Necessity defence.
Defence
The defence.
Defence
Necessity defence.
- What is the defence of necessity, and how is it limited in this jurisdiction, in general terms? provenance
- Is the user asking for legal advice about a case? boundary
Needs
Basic necessities.
Needs
Basic necessities.
- What count as basic necessities in this welfare or consumer context? provenance
- Which support applies? provenance
Reason Practical reasoning.
Argument
Claims of necessity.
Argument
Claims.
- Is a claim that something is necessary justified, or is it an assumption? boundary
- What alternatives exist? action
Language
Modal language.
Language
Modal language.
- How do words like must, need and have to express necessity in this language? definition
- How are they translated? action
Classifiers Filled
- Family
- Thing Registry
- Category
- Cross-cutting context
- Entry kind
- thing
- Plane
- XCT
- Domain
- XCT.REL
What it is Filled
The property of being a necessary condition for another statement: statement P is necessary for statement Q when Q implies P, so Q cannot be true unless P is true, although P alone need not imply Q.
Why it exists Filled
Let an agent explain necessary conditions, identify the direction of implication between statements, distinguish necessity from sufficiency, and assess whether a claimed requirement follows from stated premises.
Distinguishing features Filled
- Necessity relates a condition to another statement.
- If P is necessary for Q, then Q implies P.
- A necessary condition need not be sufficient.
- A condition can be both necessary and sufficient.
What robots and AI may and may not do Filled
Must not
- Present a choice as necessary when alternatives exist, in order to pressure people.
- Infer that a necessary condition is sufficient without justification.
- Present an unsupported implication as an established necessary condition.
Only with a human decision
- Relying on a claim of necessity to justify an action that harms someone requires human review.
May
- Explain necessary conditions using statements and their implications.
- Identify proposed necessary conditions and assess them against stated premises.
- Distinguish necessary conditions from sufficient conditions and modal necessity.
Moral aspects Filled
- Claims of necessity are often used to justify harm and to override rights.
- Misusing the idea can shut down debate about real alternatives.
Who is affected
- People affected by decisions justified as necessary are affected.
- People relying on arguments about necessary conditions are affected.
Owners Filled
Steward
Nobody owns the concept; it is shared knowledge in logic.
Links to other meta-models Filled
parent
- Q1191527 - registry parent class
- Q1516917 - registry parent class
related
- modality - category
- dependency - category
- logic - field
- possibility - related modality
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.necessity
- Wikidata: Q2301186 (https://www.wikidata.org/wiki/Q2301186)
Direct properties not applicable Not applicable
Not applicable
Plane XCT: no invented physical properties.
Recognition optional Filled
- The expression Q implies P identifies P as a necessary condition for Q.
- The expression Q only if P also identifies P as necessary for Q.
- Sufficiency is a distinct relation.
- Not physical; a concept in reasoning and law.
Capabilities and actions required Filled
- distinguish logical, metaphysical and practical necessity
- explain modal logic basics
- explain the legal defence of necessity in general terms
- identify basic necessities in policy contexts
Hazards and failure modes required Filled
- Confusing a necessary condition with modal necessity can misrepresent an argument.
- Confusing necessary and sufficient conditions can reverse an implication.
- Treating an unsupported assumption as a necessary condition can produce an invalid conclusion.
Standards and interfaces required Filled
- Criminal law on necessity and duress
- Standards defining basic necessities in welfare law
Context of use required Filled
- Reasoning about what must be the case or must be done.
- logical and metaphysical necessity
- nomological and causal necessity
- practical necessity and needs
- legal necessity defence
- necessary conditions
Sources Filled
- Wikidata item Q2301186: necessity - identity and sense of the item
- Wikipedia: Necessity (logic) - general description of the item
Open questions
- Should each sense be a separate entry?
- How should modal logic resources be linked?
- How should legal defences be localised?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q2301186/spec.json