forces By means of the property chain defined, the assertion that links a qualifier to the relative claim is automatically inferred starting from the high-level description of an argument (realized through the sub-properties of 'involves' and their inverse properties). A qualifier that expresses as degree of force concerning a claim of an argument. :my-qualifier a amo:Qualifier ; amo:forces :my-claim . :my-claim a amo:Claim . is backing in An argumentative entity linked to an argument in which it is considered a backing. :my-backing amo:isBackingIn :my-argument . :my-argument a amo:Argument . relates to An argumentation entity relates to another one in some way - for example, it is the evidence that is used to prove a claim of an argument. :my-evidence a amo:Evidence ; amo:relatesTo :my-claim . :my-claim a amo:Claim . 1 backing Sort of credentials that certifies the warrant - e.g., the OWL 2 document specifications. :my-backing a amo:Backing ; amo:isBackingIn :my-argument ; amo:backs :my-warrant . has evidence An argument includes an evidence as one of its (mandatory) components. :my-argument a amo:Argument ; amo:hasEvidence :my-evidence . 1 is claim in An argumentative entity linked to an argument in which it is considered a claim. :my-claim amo:isClaimIn :my-argument . :my-argument a amo:Argument . has backing An argument includes a backing as one of its (optional) components. :my-argument a amo:Argument ; amo:hasBacking :my-backing . leads to A warrant that points to a claim from the related evidence within an argument. By means of the property chain defined, the assertion that links a warrant to the relative claim is automatically inferred starting from the high-level description of an argument (realized through the sub-properties of 'involves' and their inverse properties). :my-warrant a amo:Warrant ; amo:leadsTo :my-claim . :my-claim a amo:Claim . has rebuttal An argument includes a rebuttal as one of its (optional) components. :my-argument a amo:Argument ; amo:hasRebuttal :my-rebuttal . supports An evidence that supports a warrant of an argument. :my-evidence a amo:Evidence ; amo:supports :my-warrant . :my-warrant a amo:Warrant . is valid unless By means of the property chain defined, the assertion that links a claim to the relative rebuttal is automatically inferred starting from the high-level description of an argument (realized through the sub-properties of 'involves' and their inverse properties). A claim that is restricted by a rebuttal of an argument. :my-claim a amo:Claim ; amo:isValidUnless :my-rebuttal . :my-rebuttal a amo:Rebuttal . Argument Model Ontology (AMO) Fabio Vitali (https://orcid.org/0000-0002-7562-5203) Silvio Peroni (https://orcid.org/0000-0003-0530-4305) Sebastian Barzaghi (https://orcid.org/0000-0002-0799-1527) 2026-09-30 The **_Argument Model Ontology (AMO)_** is an OWL 2 DL ontology that aims to encode the [Toulmin's theory](https://doi.org/10.1017/CBO9780511840005) through OWL classes and properties, in order to describe a web of inter-linked entities that participate, with a specific role, in one or more arguments. Toulmin's model of argument focuses on the justificatory function of argumentation: rather than evaluating arguments through formal logic, it describes how people, in practice, put forward a claim and then justify it. According to this model, every practical argument can be analysed in terms of six interrelated components. Three of them are essential: the claim to be established, the evidence (or data) on which it is founded, and the warrant that bridges from the evidence to the claim. The other three may be omitted in some arguments: the backing that certifies the warrant, the qualifier that expresses the degree of certainty of the claim, and the rebuttal that states the conditions under which the claim would not hold.  AMO models an argument through the class `amo:Argument`, whose components are instances of `amo:Claim`, `amo:Evidence`, `amo:Warrant`, `amo:Backing` and `amo:Rebuttal`, all grouped under the class `amo:ArgumentationEntity`, and of `amo:Qualifier`. An argument is linked to its components through the sub-properties of `amo:involves` (i.e., `amo:hasClaim`, `amo:hasEvidence`, `amo:hasWarrant`, `amo:hasBacking`, `amo:hasQualifier` and `amo:hasRebuttal`), and each argument must have exactly one claim and at least one evidence and one warrant. The components are, in turn, linked to one another: an evidence proves a claim (`amo:proves`) and supports a warrant (`amo:supports`), a warrant leads to a claim (`amo:leadsTo`), a backing backs a warrant (`amo:backs`), a qualifier forces a claim (`amo:forces`), and a claim is valid unless a rebuttal holds (`amo:isValidUnless`). Several of these relations are automatically inferred, by means of property chains, from the description of the roles that the components hold within the argument.  AMO is aligned with the [Citation Typing Ontology (CiTO)](http://purl.org/spar/cito), an ontology for the characterization of citations, both factually and rhetorically that forms part of [SPAR, a suite of Semantic Publishing and Referencing Ontologies](http://sparontologies.net). ## Examples of use In the following subsections, we introduce some examples to showcase how to use AMO. The prefixes that are used in all the examples provided below are defined as follows: @prefix amo: <http://purl.org/spar/amo/> . @prefix : <http://example.org/> . ### Describing the components of an argument Consider the argument "This ontology was developed in OWL, and since an ontology developed in OWL is a consistent OWL ontology, as stated by the OWL 2 specifications, this is presumably a consistent OWL ontology, unless a reasoner for OWL 2 proves that it is not consistent". The argument can be described from a high-level perspective by stating which argumentation entities it involves and which role each of them holds. :argument a amo:Argument ; amo:hasClaim :consistency-claim ; amo:hasEvidence :developed-in-owl ; amo:hasWarrant :owl-warrant ; amo:hasBacking :owl2-spec ; amo:hasQualifier :presumably ; amo:hasRebuttal :reasoner-rebuttal . :consistency-claim a amo:Claim . :developed-in-owl a amo:Evidence . :owl-warrant a amo:Warrant . :owl2-spec a amo:Backing . :presumably a amo:Qualifier . :reasoner-rebuttal a amo:Rebuttal . ### Describing the relations between argumentation entities The same argument can be described from a factual perspective, by stating how its argumentation entities are linked to one another. The relations between evidence and claim, warrant and claim, qualifier and claim, and claim and rebuttal can also be inferred from the high-level description through the property chains defined in AMO. :developed-in-owl amo:proves :consistency-claim ; amo:supports :owl-warrant . :owl-warrant amo:leadsTo :consistency-claim . :owl2-spec amo:backs :owl-warrant . :presumably amo:forces :consistency-claim . :consistency-claim amo:isValidUnless :reasoner-rebuttal . ## Competency Questions AMO can be used for answering several questions related to arguments and how argumentation entities are related to each other. In the following subsections, some of them are introduced together with their respective SPARQL queries. The prefixes that are used in all the SPARQL queries provided below are defined as follows: PREFIX amo: <http://purl.org/spar/amo/> PREFIX : <http://example.org/> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> ### CQ1 What is the claim of a given argument, and which evidence proves it? SELECT ?claim ?evidence WHERE { :argument amo:hasClaim ?claim ; amo:hasEvidence ?evidence . } ### CQ2 Which warrants lead to a given claim, and which backings attest them? SELECT ?warrant ?backing WHERE { ?warrant amo:leadsTo :consistency-claim . OPTIONAL { ?backing amo:backs ?warrant } } ### CQ3 What is the degree of force of a given claim, and under which rebuttals is it not valid? SELECT ?qualifier ?rebuttal WHERE { OPTIONAL { ?qualifier amo:forces :consistency-claim } OPTIONAL { :consistency-claim amo:isValidUnless ?rebuttal } } The Argument Model Ontology (AMO) 1.0.1 Peroni, S., Tomasi, F., Vitali, F., & Zingoni, J. (2013, January). Semantic lenses as exploration method for scholarly articles. In Italian Research Conference on Digital Libraries (pp. 118-129). Berlin, Heidelberg: Springer Berlin Heidelberg. DOI: https://doi.org/10.1007/978-3-642-54347-0_13. 2011-05-04 2011-05-04 2026-09-30 TBA amo http://purl.org/spar/amo bibliometrics argument model scholarly publishing scientometrics semantic publishing evidence A fact that represents a foundation for the claim - e.g., 'This ontology was developed in OWL'. :my-evidence a amo:Evidence ; amo:isEvidenceIn :my-argument ; amo:proves :my-claim . argumentation entity An entity that takes part in an argument according to the 'Toulmin model of argument'. :my-claim a amo:ArgumentationEntity ; amo:isInvolvedIn :my-argument . argument An argument, or practical argument according to the 'Toulmin model of argument', focuses on the justificatory function of argumentation: practical arguments first find a claim of interest, and then provide justification for it. Each argument must be analyzed according to six interrelated components: claim, evidence, warrant, backing, rebuttal and qualifier. The first three elements, 'claim', 'data' and 'warrant', are considered as the essential components of practical arguments, while the second triad, 'qualifier', 'backing', and 'rebuttal', may not be needed in some arguments. :my-argument a amo:Argument ; amo:hasClaim :my-claim ; amo:hasEvidence :my-evidence ; amo:hasWarrant :my-warrant ; amo:hasBacking :my-backing ; amo:hasQualifier :my-qualifier ; amo:hasRebuttal :my-rebuttal . has qualifier An argument includes a qualifier as one of its (optional) components. :my-argument a amo:Argument ; amo:hasQualifier :my-qualifier . backs A backing that attests the warrant of an argument. :my-backing a amo:Backing ; amo:backs :my-warrant . :my-warrant a amo:Warrant . involves This property and its sub-properties serve to describe an argument from an high-level perspective (i.e., which argumentation entities take part in it and what role they hold) rather than from a factual point of view (i.e., how argumentation entities are inter-linked between them). An argument involves an argumentation entity (claim, evidence, warrant, backing, rebuttal) or a qualifier. :my-argument a amo:Argument ; amo:involves :my-claim, :my-evidence, :my-warrant . is qualifier in An sentence or word linked to an argument with the scope of qualifying the argument claim. :my-qualifier amo:isQualifierIn :my-argument . :my-argument a amo:Argument . is involved in An argumentation entity involved in the presentation of an argument. :my-claim amo:isInvolvedIn :my-argument . :my-argument a amo:Argument . warrant A statement bridging from the evidence to the claim - e.g., 'An ontology developed in OWL is a consistent OWL ontology'. :my-warrant a amo:Warrant ; amo:isWarrantIn :my-argument ; amo:leadsTo :my-claim . is rebuttal in An argumentative entity linked to an argument in which it is considered a rebuttal. :my-rebuttal amo:isRebuttalIn :my-argument . :my-argument a amo:Argument . is evidence in An argumentative entity linked to an argument in which it is considered an evidence. :my-evidence amo:isEvidenceIn :my-argument . :my-argument a amo:Argument . proves By means of the property chain defined, the assertion that links an evidence to the relative claim is automatically inferred starting from the high-level description of an argument (realized through the sub-properties of 'involves' and their inverse properties). An evidence that founds a claim of an argument. :my-evidence a amo:Evidence ; amo:proves :my-claim . :my-claim a amo:Claim . claim A fact that must be established - e.g., 'This is a consistent OWL ontology'. :my-claim a amo:Claim ; amo:isClaimIn :my-argument ; amo:isValidUnless :my-rebuttal . 1 has claim An argument includes a claim as one of its (mandatory) components. :my-argument a amo:Argument ; amo:hasClaim :my-claim . qualifier Words or phrases that express the degree of certainty of the claim such as “certainly”, “possible”, “probably”, “presumably”, etc. :my-qualifier a amo:Qualifier ; amo:isQualifierIn :my-argument ; amo:forces :my-claim . is warrant in An argumentative entity linked to an argument in which it is considered a warrant. :my-warrant amo:isWarrantIn :my-argument . :my-argument a amo:Argument . has warrant An argument includes a warrant as one of its (mandatory) components. :my-argument a amo:Argument ; amo:hasWarrant :my-warrant . rebuttal Restrictions that may be applied to the claim - 'Unless a reasoner for OWL 2 proves that it is not consistent'. :my-rebuttal a amo:Rebuttal ; amo:isRebuttalIn :my-argument . :my-claim amo:isValidUnless :my-rebuttal .