Publications on Deontic Logic and Normative Reasoning
- Grigoris Antoniou, David Billington, Guido Governatori, and
Michael J. Maher.
-
On the modeling and analysis of
regulations.
In Proceedings of the Australian Conference Information Systems,
pages 20-29, 1999.
Abstract:Regulations are a wide-spread and important part of
government and business. They codify how products must be made and processes
should be performed. Such regulations can be difficult to understand and
apply. In an environment of growing complexity of, and change in, regulation,
automated support for reasoning with regulations is becoming increasingly
necessary. In this paper we report on ongoing work which aims at providing
automated support for the drafting and use of regulations using logic
modelling techniques. We highlight the support that can be provided by logic
modelling, describe the technical foundation of our project, and report on
the status of the project and the next steps.
 
- Grigoris Antoniou, Nikos Dimaresis, and Guido
Governatori.
-
A
system for modal and deontic defeasible reasoning.
In Mehmet A. Orgun and John Thornton, editors, 20th Australian Joint
Conference on Artificial Intelligence, AI 2007,
LNAI 4830, pages 609-613. Springer, 2007.
Copyright © 2007 Springer.
Abstract:
Defeasible reasoning is a well-established nonmonotonic reasoning approach that
has recently been combined with semantic web technologies. This paper describes
modal and deontic extensions of defeasible logic, motivated by potential
applications for modelling multi-agent systems and policies. It describes a
logic metaprogram that captures the underlying intuitions, and outlines an
implemented system.
- Alberto Artosi, Paola Cattabriga, and Guido
Governatori.
-
An automated approach to normative
reasoning.
In Joost Breuker, editor, Artificial Normative Reasoning, pages
132-145, Amsterdam, 1994. ECAI'94.
 
- Alberto Artosi, Paola Cattabriga, and Guido
Governatori.
-
KED: A deontic theorem prover.
In Carlo Biagioli, Giovanni Sartor, and Daniela Tiscornia, editors,
Workshop on Legal Application of Logic Programming, pages 60-76,
Firenze, 1994. ICLP'94, IDG.
 
- Alberto Artosi and Guido Governatori.
-
A tableaux methodology for deontic
conditional logics.
In ΔEON'98, 4th International Workshop on Deontic Logic in
Computer Science, pages 65-81, Bologna, 1998. CIRFID.
Abstract:In this paper we present a theorem proving methodology
for a restricted but significant fragment of the conditional language made up
of (boolean combinations of) conditional statements with unnested
antecedents. The method is based on the possible world semantics for
conditional logics. The label formalism introduced in \cite{cade,jelia} to
account for the semantics of normal modal logics is easily adapted to the
semantics of conditional logics by simply indexing labels with formulas. The
inference rules are provided by the propositional system KE+ - a
tableau-like analytic proof system devised to be used both as a refutation
and a direct method of proof - enlarged with suitable elimination rules for
the conditional connective. The theorem proving methodology we are going to
present can be viewed as a first step towards developing an appropriate
algorithmic framework for several conditional logics for (defeasible)
conditional obligation.
 
- Alberto Artosi, Guido Governatori, and Giovanni
Sartor.
-
Towards a computational treatment of deontic
defeasibility.
In Mark Brown and José Carmo, editors, Deontic Logic Agency and
Normative Systems, Workshop on Computing, pages 27-46, Berlin, 1996.
Springer-Verlag, Copyright © 1996
Springer-Verlag.
Abstract:In this paper we describe an algorithmic framework for a
multi-modal logic arising from the combination of the system of modal
(epistemic) logic devised by Meyer and van der Hoek for dealing with
nonmonotonic reasoning with a deontic logic of the Jones and Pörn-type. The
idea behind this (somewhat eclectic) formal set-up is to have a modal
framework expressive enough to model certain kinds of deontic defeasibility,
in particular by taking into account preferences on norms. The appropriate
inference mechanism is provided by a tableau-like modal theorem proving
system which supports a proof method closely related to the semantics of
modal operators. We argue that this system is particularly well-suited for
mechanizing nonmonotonic forms of inference in a monotonic multi-modal
setting.
 
- Guido Boella, Guido Governatori, Antonino Rotolo, and
Leendert van der Torre.
-
A
formal study on legal compliance and interpretation.
In Thomas Meyer and Eugenia Ternovska, editors, 13 International Workshop
on Non-Monotonic Reasoning (NMR 2010). CEUR Workshop Proceedings, 2010.
Abstract: This paper proposes a logical framework to capture the
norm change power and the limitations of the judicial system in revising the
set of constitutive rules defining the concepts on which the applicability of
norms is based. In particular, we reconstruct the legal arguments leading to
an extensive or restrictive interpretation of norms.
 
- Guido Boella, Guido Governatori, Antonino Rotolo, and
Leendert van der Torre.
-
Lex minus dixit quam voluit, lex magis dixit quam voluit: A formal
study on legal compliance and interpretation.
In P. Casanovas, U. Pagallo, G. Ajani, and G. Sartor, editors, AI
approaches to the complexity of legal systems, LNAI, Berlin, 2010.
Springer, Copyright © 2010 Springer.
Abstract: This paper argues in favour of the necessity of
dynamically restricting and expanding the applicability of norms regulating
computer systems like multiagent systems, in situations where the compliance
to the norm does not achieve the purpose of the norm. We propose a logical
framework which distinguishes between constitutive and regulative norms and
captures the norm change power and at the same time the limitations of the
judicial system in dynamically revising the set of constitutive rules
defining the concepts on which the applicability of norms is based. In
particular, the framework is used to reconstruct some interpretive arguments
described in legal theory such as those corresponding to the Roman maxims
lex minus dixit quam voluit and lex magis dixit quam voluit.
The logical framework is based on an extension of defeasible logic.
 
- Guido Boella, Guido Governatori, Antonino Rotolo, and Leendert
van der Torre.
-
A
logical understanding of legal interpretation.
In Proceedings of KR 2010. AAAI, 2010.
Abstract: If compliance with a norm does not achieve its purpose,
then its applicability must dynamically be restricted or expanded. Legal
interpretation is a mechanism from law allowing norms to be adapted to
unforeseen situations. We model this mechanism for norms regulating computer
systems by representing the purpose of norms by social goals and by revising
the constitutive rules defining the applicability of norms. We illustrate the
interpretation mechanism by examples.
 
- Dov M. Gabbay and Guido Governatori.
-
Dealing with label dependent deontic
modalities.
In Paul McNamara and Henry Prakken, editors, Norms, Logics and
Information Systems. New Studies in Deontic Logic, pages 311-330. IOS
Press, Amsterdam, 1998.
Abstract:In this paper, following Scott's advice, we argue that
normative reasoning can be represented in a multi-setting framework; in
particular in a multi-modal one, where modalities are indexed. Indexed
modalities can model several aspects involved in normative reasoning. Systems
are combined using Gabbay's fibring methodology which provides complete
semantics that can be used to model a labelled tableau-like proofs system.
 
- Jonathan Gelati, Guido Governatori, Antonino Rotolo, and
Giovanni Sartor.
-
Declarative power, representation, and
mandate: A formal anaysis.
In Trevor Bench-Capon, Aspassia Daskalopulu, and Radboudb Winkels, editors,
Legal Knowledge and Information Systems, number 89 in Frontieres in
Artificial Intelligence and Applications, pages 41-52. IOS Press, Amsterdam,
2002.
Abstract:In this paper we provide a formal framework for
developing the idea of normative co-ordination. We argue that this idea is
based on the assumption that agents can achieve flexible co-ordination by
conferring normative positions to other agents. These positions include
duties, permissions, and powers. In particular, we introduce the idea of
declarative power, which consists in the capacity of the power-holder of
creating normative positions, involving other agents, simply by
``proclaiming'' such positions. In addition, we account also for the concepts
of representation, consisting in the representative's capacity of acting in
the name of his principal, and of mandate, which corresponds the mandatee's
duty to act as the mandator has requested. Finally, we show how the above
framework can be applied to the contract-net protocol.
 
- Jonathan Gelati, Guido Governatori,
Antonino Rotolo, and Giovanni Sartor.
-
Normative autonomy and normative co-ordination: Declarative power,
representation, and mandate.
Artificial Intelligence and Law, 12 (1-2), 53-81.
2004. Copyright © 2004 Springer. The original publication is
available at
www.springerlink.com
Abstract:In this paper we provide a formal analysis of the
idea of normative co-ordination. We argue that this
idea is based on the assumption that agents can
achieve flexible co-ordination by conferring
normative positions to other agents. These positions
include duties, permissions, and powers. In
particular, we explain the idea of declarative
power, which consists in the capacity of the
power-holder of creating normative positions,
involving other agents, simply by ``proclaiming''
such positions. In addition, we account also for the
concepts of representation, namely the
representative's capacity of acting in the name of
his principal, and of mandate, which is the
mandatee's duty to act as the mandator has
requested. Finally, we show how the framework can be
applied to represent the contract-net protocol. Some
brief remarks on future research and applications
conclude this contribution.
 
- Thomas F. Gordon, Guido Governatori, and
Antonino Rotolo.
-
Rules and norms: Requirements for rule interchange languages in the legal domain.
In Guido Governatori, John Hall, and Adrian Paschke, editors, Rule
Representation, Interchange and Reasoning on the Web, number 5858 in
LNCS, pages 282-296, Berlin, 5-7 November 2009. Springer, Copyright © 2009 Springer.
Abstract: In this survey paper we summarize the requirements for
rule interchange languages for applications in the legal domain and use these
requirements to evaluate RuleML, SBVR, SWRL and RIF. We also present the
Legal Knowledge Interchange Format (LKIF), a new rule interchange format
developed specifically for applications in the legal domain.
 
- Guido Governatori.
-
Un modello formale per il ragionamento
giuridico.
PhD thesis, CIRFID, University of Bologna, Bologna, 1997.
 
- Guido Governatori.
-
Ideality and subideality from a
computational point of view.
In Alberto Artosi, Manuel Atienza, and Hajme Yoshino, editors, From
Practical Reason to Legal Computer Science. Legal Computer Science,
volume Part II, pages 315-329. Clueb, Bologna, 1998.
Abstract:In this paper we suggest ways in which logic and law may
usefully relate; and we present an analytic proof system dealing with the
Jones Pörn's deontic logic of Ideality and Subideality, which offers some
suggestions about how to embed legal systems in label formalism.
 
- Guido Governatori.
-
Defeasible description logic.
In Grigoris Antoniou and Harold Boley, editors, Rules and Rule Markup
Languages for the Semantic Web: Third International Workshop, RuleML
2004, number 3323 in LNCS, pages 98-112, Berlin, 8 November 2004.
Springer-Verlag Copyright © 2004, Springer. The original
pubblication is available at www.springerlink.com
Abstract:We propose to extend description logic with defeasible
rules, and to use the inferential mechanism of defeasible logic to reason
with description logic constructors.
 
- Guido Governatori.
-
Representing business contracts in
{RuleML}.
International Journal of Cooperative Information Systems, 14
no. 2-3, June-September 2005.
Abstract:This paper presents an approach for the specification
and implementation of translating contracts from a human-oriented form into
an executable representation for monitoring. This will be done in the setting
of \RuleML. The task of monitoring contract execution and performance
requires a logical account of deontic and defeasible aspects of legal
language; currently such aspects are not covered by \RuleML; accordingly we
show how to extend it to cover such notions. From its logical form, the
contract will be thus transformed into a machine readable rule notation and
eventually implemented as executable semantics via any mark-up languages
depending on the client's preference, for contract monitoring purposes.
 
- Guido Governatori.
-
Law, logic and
business processes.
In Third International Workshop on Requirements Engineering and Law.
IEEE, 2010, Copyrigth © 2010 IEEE.
Abstract: Since its inception one of the aims of legal
informatics has been to provide tools to support and improve the day to day
activities of legal and normative practice and a better understanding of
legal reasoning. The internet revolutions, where more and more daily
activities are routinely performed with the support of ITC tools, offers new
opportunities to legal informatics. We argue that the current technology
begins to be mature enough to embrace in the challenge to make intelligent
ICT support widespread in the legal and normative domain. In this paper we
examine a logical model to encode norms and we use the formalisation of
relevant law and regulations for regulatory compliance for business
processes.
 
- Guido Governatori.
-
A
logic framework of normative-based contract management.
In Satoshi Tojo, editor, Fourth International Workshop on
Juris-informatics (JURISIN 2010), November 18-19 2010.
Abstract: In this paper an extended Defeasible Logic framework is
presented to do the representation and reasoning work for the normative-based
contract management. A simple case based on FIDIC is followed as the usage
example. This paper is based on the idea that normative concepts and
normative rules should play the decisive roles in the normative-based
contract management. Those normative concepts and rules are based on the
normative literals and operators like action, obligation, permission and
violation. The normative reduction is based on the normative concepts,
normative connections and normative rules, especially on the superiority
relation over the defeasible rules.
 
- Guido Governatori.
-
On
the relationship between Carneades and defeasible logic.
In Tom van Engers, editor, Proceedings of the 13th International
Conference on Artificial Intelligence and Law (ICAIL 2011). ACM Press,
2011. Copyrigth © 2011 ACM Press.
Abstract: We study the formal relationships between the
inferential aspects of Carneades (a general argumentation framework) and
Defeasible Logic. The outcome of the investigation is that the current proof
standards proposed in the Carneades framework correspond to some variants of
Defeasible Logic.
 
- Guido Governatori, Marlon Dumas, Arthur H.M. ter Hofstede,
and Phillipa Oaks.
-
A formal approach to protocols and strategies
for (legal) negotiation.
In Henry Prakken, editor, Procedings of the 8th International Conference
on Artificial Intelligence and Law, pages 168-177. IAAIL, ACM Press,
2001, Copyright ©
2001 ACM.
Abstract:We propose a formal and executable framework for
expressing protocols and strategies for automated (legal) negotiation. In
this framework a party involved in a negotiation is represented through a
software agent composed of four modules: (i) a communication module which
manages the interaction with the other agents; (ii) a control module; (iii) a
reasoning module specified as a defeasible theory; and (iv) a knowledge base
which bridges the control and the reasoning modules, while keeping track of
past decisions and interactions. The choice of defeasible logic is justified
against a set of desirable criteria for negotiation automation languages.
Moreover, the suitability of the framework is illustrated through two case
studies.
 
- Guido Governatori, Jonathan Gelati, Antonino Rotolo, and
Giovanni Sartor.
-
Actions, institutions, powers.
preliminary notes.
In Gabriela Lindemann, Daniel Moldt, Mario Paolucci, and Bin Yu, editors,
International Workshop on Regulated Agent-Based Social Systems: Theories
and Applications (RASTA'02), volume 318 of Mitteilung, pages
131-147, 2002. Fachbereich Informatik, Universität
Hamburg.
Abstract:In this paper we analyse some logical notions relevant
for representing the dynamics of institutionalised organisations. In
particular, some well-known action concepts introduced in the
Kanger-Lindahl-Pörn logical theory of agency are discussed and integrated.
Secondly, moving from the work of Jones and Sergot, a logical
characterisation is provided of the ideas of institutional links,
``counts-as'' connections, and institutional facts. This approach is then
enriched by a new modal operator $\mathit{proc}$, intended to account for the
autonomous and decentralised creation of new institutional facts and
normative positions within institutions.
 
- Guido Governatori, Jörg Hoffmann, Shazia Sadiq, and Ingo
Weber.
-
Detecting
regulatory compliance for business process models through semantic
annotations.
In 4th International Workshop on Business Process Design,
Milan, 1 September 2008 2008.
Abstract: A given business process may face a large number of
regulatory obligations the process may or comply with. Providing tools and
techniques through which an evaluation of the compliance degree of a given
process can be undertaken is seen as a key objective in emerging business
process platforms. We address this problem through a diagnostic framework
that provides the ability to assess the compliance gaps present in a given
process. Checking whether a process is compliant with the rules involves
enumerating all reachable states and is hence, in general, a hard search
problem. The approach taken here allows to provide useful diagnostic
information in polynomial time. The approach is based on two underlying
techniques. A conceptually faithful representation for regulatory obligations
is firstly provided by a formal rule language based on a non-monotonic
deontic logic of violations. Secondly, processes are formalized through
semantic annotations that allow a logical state space to be created. The
intersection of the two allows us to devise an efficient method to detect
compliance gaps; the method guarantees to detect all obligations that will
necessarily arise during execution, but that will not necessarily be
fulfilled.
 
- Guido Governatori, Joris Hulstijn, Règis Riveret, and
Antonino Rotolo.
-
On the representation of deadlines in a rental agreement.
In Arno R. Lodder and Laurens Mommers, editors, Legal Knowledge and
Information Systems, pages 167-168. IOS Press, Amsterdam, 2007.
Abstract: The paper provides a conceptual analysis of deadlines,
represented in Temporal Modal Defeasible Logic. The typology is based on the
following parameters: kind of deontic operator, maintenance or achievement,
presence of explicit sanctions, and persistence after the deadline. The
adequacy of the typology is validated against a case study of a rental
agreement.
- Guido Governatori, Joris Hulstijn, Régis
Riveret, and Antonino Rotolo.
-
Characterising deadlines in temporal modal defeasible logic.
In Mehmet A. Orgun and John Thornton, editors, 20th Australian Joint
Conference on Artificial Intelligence, AI 2007,
LNAI 4830, pages 486-496. Springer, 2007.
Copyright © 2007 Springer.
Abstract: We provide a conceptual analysis of several kinds of
deadlines, represented in Temporal Modal Defeasible Logic. The paper presents
a typology of deadlines, based on the following parameters: deontic operator,
maintenance or achievement, presence or absence of sanctions, and persistence
after the deadline. The deadline types are illustrated by a set of examples.
- Guido Governatori and Renato Iannella.
-
Modelling and reasoning languages for social networks policies.
In Enterprise Distributed Object Computing Conference, 2009. EDOC '09.
IEEE International, pages 193-200. IEEE, 2009, Copyright © 2009 IEEE.
Abstract: Policy languages (such as privacy and rights) have had
little impact on the wider community. Now that Social Networks have taken
off, the need to revisit Policy languages and realign them towards Social
Networks requirements has become more apparent. One such language is explored
as to its applicability to the Social Networks masses. We also argue that
policy languages alone are not sufficient and thus they should be paired with
reasoning mechanisms to provide precise and unambiguous execution models of
the policies. To this end we propose a computationally oriented model to
represent, reason with and execute policies for Social Networks.
 
- Guido Governatori and Renato Iannella.
-
A
modelling and reasoning framework for social networks policies.
Enterprise Information Systems, 2010 Copyrigth © 2010
Taylor & Francis.
Abstract: Policy languages (such as privacy and rights) have had
little impact on the wider community. Now that Social Networks have taken
off, the need to revisit Policy languages and realign them towards Social
Networks requirements has become more apparent. One such language is
explored as to its applicability to the Social Networks masses. We also argue
that policy languages alone are not sufficient and thus they should be paired
with reasoning mechanisms to provide precise and unambiguous execution models
of the policies. To this end we propose a computationally oriented model to
represent, reason with and execute policies for Social Networks.
 
- Guido Governatori, Alessio Lomuscio, and Marek
Sergot.
-
A tableaux system for deontic interpreted
systems.
In Tamás D. Gedeon and Lance Chun Che Fung, editors, AI 2003:
Advances in Artificial Intelligence, volume 2903 of LNAI, pages
339-351, Springer-Verlag, Berlin, 2003. Copyright © 2003 Springer-Verlag.
Abstract:We develop a labelled tableaux system for the modal
logic $KD45^i-j_n$ extended with epistemic notions. This logic
characterises a particular type of interpreted systems used to represent and
reason about states of correct and incorrect functioning behaviour of the
agents in a system, and of the system as a whole. The resulting tableaux
system provides a simple decision procedure for the logic. We discuss these
issues and we illustrate them with the help of simple examples.
 
- Guido Governatori and Zoran Milosevic.
-
Dealing with contract violations: formalism and domain specific language.
Proceedings of EDOC 2005. IEEE Press,
2005, pp. 46-57. Copyright © 2005 IEEE.
Abstract:This paper presents a formal system for
reasoning about violations of obligations in
contracts. The system is based on the formalism for
the representation of contrary-to-duty
obligations. These are the obligations that take
place when other obligations are violated as
typically applied to penalties in contracts. The
paper shows how this formalism can be mapped onto
the key policy concepts of a contract specification
language. This language, called Business Contract
Language (BCL) was previously developed to express
contract conditions of relevance for run time
contract monitoring. The aim of this mapping is to
establish a formal underpinning for this key subset
of BCL.
 
- Guido Governatori, and Zoran Milosevic
-
An Approach for Validating BCL Contract Specifications
In Claudio Bartolini, Guido Governatori, and Zoran Milosevic (eds).
Proceedings on the 2nd EDOC Workshop on Contract Architecures and
Languages (CoALa 2005). Enschede, NL, 20 September 2005.
IEEE Press.
Abstract:We continue the study, started in [5], on the formal
relationships between a domain specific contract
language (BCL) and the logic of violation (FCL)
proposed in [6,7]. We discuss the use of logical
methods for the representation and analysis of
business contracts. The proposed analysis is based
on the notions of normal and canonical forms of
contracts expressed in FCL. Finally we present a
mapping from FCL to BCL that can be used to provide
an executable model of a formal representation of a
contract.
 
- Guido Governatori and Zoran Milosevic.
-
A Formal Analysis of a Business Contract Language.
International Journal of Cooperative Information Systems 15, in print. Copyright
© 2006 World Scientific Press.
Abstract: This paper presents a formal system for reasoning
about violations of obligations in contracts. The
system is based on the formalism for the
representation of contrary-to-duty
obligations. These are the obligations that take
place when other obligations are violated as
typically applied to penalties in contracts. The
paper shows how this formalism can be mapped onto
the key policy concepts of a contract specification
language, called Business Contract Language (BCL),
previously developed to express contract conditions
for run time contract monitoring. The aim of this
mapping is to establish a formal underpinning for
this key subset of BCL.
 
- Guido Governatori, Zoran
Milosevic, and Sahzia Sadiq
-
Compliance checking between business processes and business contracts
10th International Enterprise Distributed Object Computing Conference
(EDOC 2006). IEEE Press, 2006,
pp. 221-232. Copyright © 2006
IEEE.
Abstract: It is a typical scenario that many
organisations have their business processes specified independently
of their business contracts. This is because of the lack of
guidelines and tools that facilitate derivation of processes from
contracts but also because of the traditional mindset of treating
contracts separately from business processes. This paper provides a
solution to one specific problem that arises from this situation,
namely the lack of mechanisms to check whether business processes
are compliant with business contracts. The central part of the
paper are logic based formalism for describing both the semantics
of contract and the semantics of compliance checking procedures.
 
- Guido Governatori, Vineet Padmanabhan, Antonino
Rotolo, and Abdul Sattar.
-
A defeasible
logic for modelling policy-based intentions and motivational attitudes.
Logic Journal of the IGPL, 17(3), 2009. Copyright © 2009 Oxford University
Press.
Abstract: In this paper we show how defeasible logic
could formally account for the non-monotonic properties involved in
motivational attitudes like intention and obligation. Usually,
normal modal operators are used to represent such attitudes wherein
classical logical consequence and the rule of necessitation comes into play
i.e., $\vdash A / \vdash \Box A$, that is from $\vdash A$ derive $\vdash\Box
A$. This means that such formalisms are affected by the Logical
Omniscience problem. We show that policy-based intentions exhibit
non-monotonic behaviour which could be captured through a non-monotonic
system like defeasible logic. To this end we outline a defeasible logic of
intention that specifies how modalities can be introduced and manipulated in
a non-monotonic setting without giving rise to the problem of logical
omniscience. In a similar way we show how to add deontic modalities
defeasibly and how to integrate them with other motivational attitudes like
beliefs and goals. Finally we show that the basic aspect of the BOID
architecture is captured by this extended framework.
 
- Guido Governatori, Monica Palmirani, Régis Riveret,
Antonino Rotolo and Giovanni Sartor.
-
Normative Modifications in Defeasible Logic.
In Marie-Francine Moens, editor, Jurix'05: The Eighteenth Annual Conference, in print. IOS Press, Amsterdam
2005.
Abstract:
This paper proposes a framework based on Defeasible Logic (DL) to
reason about normative modifications. We show how to express them in
DL and how the logic deals with conflicts between temporalised
normative modifications. Some comments will be given with regard to
the phenomenon of retroactivity.
 
-
Guido Governatori, and Duy Pham Hoang
-
DR-CONTRACT: An Architecture for e-Contracts in Defeasible Logic
In Claudio Bartolini, Guido Governatori, and Zoran Milosevic (eds).
Proceedings on the 2nd EDOC Workshop on Contract Architecures and
Languages (CoALa 2005). Enschede, NL, 20 September 2005.
IEEE Press.
Abstract:In this paper we present an architecture to
represent and reason on e-Contracts based on the
DR-device architecture supplemented with a deontic
defeasible logic of violation. We motivate the
choice for the logic and we show how to extend
RuleML to capture the notions relevant to describe
e-contracts for a monitoring perspective in
Defeasible Logic.
 
- Guido Governatori and Duy Hoang
Pham
-
A
Semantic Web Based Architecture for e-Contracts in Defeasible
Logic. In A. Adi, S. Stoutenberg and S. Tabet,
editors, Rules and Rule Markup Languages for the Semantic
Web. RuleML 2005, pages 145-159. LNCS 3791, Springer, Berlin,
2005. The original pubblication is available
at www.springerlink.com.
Abstract:
We introduce the DR-CONTRACT architecture to represent and reason on
e-Contracts. The architecture extends the DR-device architecture by
a deontic defeasible logic of violation. We motivate the choice for
the logic and we show how to extend \RuleML to capture the notions
relevant to describe e-contracts for a monitoring perspective in
Defeasible Logic.
 
- Guido Governatori and Duy Hoang Pham.
-
DR-CONTRACT: An Architecture for e-Contracts in Defeasible
Logic.
International Journal of Business Process Integration and
Management, 5(4), 2009.
Abstract: We introduce the DR-CONTRACT architecture to represent
and reason on e-Contracts. The architecture extends the DR-device
architecture by a deontic defeasible logic of violation. We motivate the
choice for the logic and we show how to extend RuleML to capture the notions
relevant to describe e-contracts for a monitoring perspective in Defeasible
Logic.
 
- Guido Governatori and Antonino Rotolo.
-
Logic of Violations: A Gentzen System for Reasoning with
Contrary-To-Duty Obligations
Australasian Journal of Logic 4: 193-215, 2006.
Abstract: In this paper we present a Gentzen system for
reasoning with contrary-to-duty obligations. The intuition behind
the system is that a contrary-to-duty is a special kind of normative
exception. The logical machinery to formalise this idea is taken
from substructural logics and it is based on the definition of a new
non-classical connective capturing the notion of reparational
obligation. Then the system is tested against well-known
contrary-to-duty paradoxes.
 
- Guido Governatori and Antonino Rotolo.
-
A Gentzen system for reasoning with
contrary-to-duty obligations. a preliminary study.
In Andrew J.I. Jones and John Horty, editors, Δeon'02, pages
97-116, London, May 2002. Imperial College.
Abstract:In this paper we present a Gentzen system for reasoning
with contrary-to-duty obligations. The intuition behind the system is that a
contrary-to-duty is a special kind of normative exception. The logical
machinery to formalize this idea is taken from substructural logics and it is
based on the definition of a new non-classical connective capturing the
notion of reparational obligation. Then the system is tested against
well-known contrary-to-duty paradoxes.
 
- Guido Governatori and Antonino Rotolo.
-
A computational framework for non-monotonic
agency, institutionalised power and multi-agent systems.
In Daniéle Bourcier, editor, Legal Knowledge and Inforamtion
Systems, volume 106 of Frontieres in Artificial Intelligence and
Applications, pages 151-152, IOS Press, Amsterdam, 2003.
 
- Guido Governatori and Antonino Rotolo.
-
Defeasible logic: Agency and obligation.
In Alessio Lomuscio and Donald Nute, editors, Deontic Logic in Computer
Science, number 3065 in LNAI, pages 114-128,
Springer-Verlag, Berlin, 2004. Copyright © 2004 Spinger.
Abstract:We propose a computationally oriented non-monotonic
multi-modal logic arising from the combination of agency, intention and
obligation. We argue about the defeasible nature of these notions and then we
show how to represent and reason with them in the setting of defeasible
logic.
 
- Guido Governatori and Antonino Rotolo.
-
Modelling contracts using
RuleML.
In Thomas Gordon, editor, Legal Knowledge and Information Systems,
volume 120 of Frontieres in Artificial Intelligence and
Applications, pages 141-150, Amsterdam, 2004. IOS Press.
Abstract:This paper presents an approach for the specification
and implementation of e-contracts for Web monitoring. This is done in the
setting of RuleML. We argue that monitoring contract execution
requires also a logical account of deontic concepts and of violations.
Accordingly, RuleML is extended to cover these aspects.
 
- Guido Governatori and Antonino Rotolo.
-
A
computational framework for institutional agency.
Artificial Intelligence and Law, 16 no. 1 pp. 25-52, 2008.,
Copyright © 2008 Springer.
Abstract: This paper provides a computational framework, based on
Defeasible Logic, to capture some aspects of institutional agency. Our
background is Kanger-Lindahl-Pörn account of organised interaction, which
describes this interaction within a multi-modal logical setting. This work
focuses in particular on the notions of counts-as link and on those of
attempt and of personal and direct action to realise states of affairs. We
show how standard Defeasible Logic can be extended to represent these
concepts: the resulting system preserves some basic properties commonly
attributed to them. In addition, the framework enjoys nice computational
properties, as it turns out that the extension of any theory can be computed
in time linear to the size of the theory itself.
- Guido Governatori and Antonino Rotolo.
-
An
algorithm for business process compliance.
In Enrico Francesconi, Giovani Sartor, and Daniela Tiscornia, editors,
Legal Knowledge and Information Systems (Jurix 2008),
Frontieres in Artificial Intelligence and Applications 189, pages
186-191. IOS Press, 2008.
Abstract: This paper provides a novel mechanism to check whether
business processes are compliant with business rules regulating them. The key
point is that compliance is a relationship between two sets of
specifications: the specifications for executing a business process and the
specifications regulating it.
 
- Guido Governatori and Antonino Rotolo.
-
BIO
logical agents: Norms, beliefs, intentions in defeasible logic.
Journal of Autonomous Agents and Multi Agent Systems, 2008.
Copyright © 2008 Springer.
Abstract: In this paper we follow the BOID (Belief, Obligation,
Intention, Desire) architecture to describe agents and agent types in
Defeasible Logic. We argue, in particular, that the introduction of
obligations can provide a new reading of the concepts of intention and
intentionality. Then we examine the notion of social agent (i.e., an agent
where obligations prevail over intentions) and discuss some computational and
philosophical issues related to it. We show that the notion of social agent
either requires more complex computations or has some philosophical
drawbacks.
- Guido Governatori and Antonino Rotolo.
-
Changing
legal systems: Abrogation and annulment. Part I: Revision of defeasible
theories.
In Ron van der Meyden and Leon van der Torre, editors, 9th International
Conference on Deontic Logic in Computer Science (DEON2008), Lecture
Notes in Computer Science. Springer, 2008.
Copyright © 2008 Springer.
Abstract: In this paper we investigate how to model legal
abrogation and annulment in Defeasible Logic. We examine some options that
embed in this setting, and similar rule-based systems, ideas from belief and
base revision. In both cases, our conclusion is negative, which suggests to
adopt a different logical model.
- Guido Governatori and Antonino Rotolo.
-
Changing
legal systems: Abrogation and annulment. Part II: Temporalised defeasible
logic.
In Guido Boella, Harko Verhagen, and Muindhar Singh, editors, Proceedings
of Normative Multi Agent Systems (NorMAS 2008, Luxembourg 15-16 July 2008.
Abstract: In this paper we propose a temporal extension of
Defeasible Logic to model legal modifications, such as abrogation and
annulment. Hence, this framework overcomes the difficulty, discussed
elsewhere \cite{deon-part1}, of capturing these modification types using
belief and base revision.
 
- Guido Governatori and Antonino Rotolo.
-
Changing legal systems: legal abrogations and annulments in defeasible
logic.
Logic Journal of IGPL, 18 no. 1 pp. 157-194, 2009.
Copyright © 2010 Oxford University Press.
Abstract: In this paper we investigate how to represent and
reason about legal abrogations and annulments in Defeasible Logic. We examine
some options that embed in this setting, and in similar rule-based systems,
ideas from belief and base revision. In both cases, our conclusion is
negative, which suggests to adopt a different logical model. This model
expresses temporal aspects of legal rules, and distinguishes between two main
timelines, one internal to a given temporal version of the legal system, and
another relative to how the legal system evolves over time. Accordingly, we
propose a temporal extension of Defeasible Logic suitable to express this
model and to capture abrogation and annulment. We show that the proposed
framework overcomes the difficulties discussed in regard to belief and base
revision, and is sufficiently flexible to represent many of the subtleties
characterizing legal abrogations and annulments.
 
- Guido Governatori and Antonino Rotolo.
-
How do agents comply with norms?.
In Guido Boella, Pablo Noriega, Gabriella Pigozzi, and Harko Verhagen,
editors, Normative Multi-Agent Systems, number 09121 in Dagstuhl
Seminar Proceedings, Dagstuhl, Germany, 2009. Schloss Dagstuhl -
Leibniz-Zentrum fuer Informatik, Germany.
Abstract: The import of the notion of institution in the design
of MASs requires to develop formal and efficient methods for modeling the
interaction between agents' behaviour and normative systems. This paper
discusses how to check whether agents' behaviour is compliant with the rules
regulating them. The key point of our approach is that compliance is a
relationship between two sets of specifications: the specifications for
executing a process and the specifications regulating it. We propose a
logic-based formalism for describing both the semantics of normative
specifications and the semantics of compliance checking procedures.
 
- Guido Governatori and Antonino Rotolo.
-
How do agents comply with norms?.
In IEEE/WIC/ACM International Joint Conferences on
Web Intelligence and Intelligent Agent Technologies, 2009. WI-IAT '09.
, volume 3, pages
488-491. IEEE, 2009, Copyright ©
2009 IEEE.
Abstract: The import of the notion of institution in the design
of MASs requires to develop formal and efficient methods for modeling the
interaction between agents' behaviour and normative systems. This paper
discusses how to check whether agents' behaviour complies with the rules
regulating them. The key point of our approach is that compliance is a
relationship between two sets of specifications: the specifications for
executing a process and the specifications regulating it. We propose a
formalism for describing both the semantics of normative specifications and
the semantics of compliance checking procedures.
 
- Guido Governatori and Antonino Rotolo.
-
A
conceptually rich model of business process compliance.
In Sebastian Link and Aditya Ghose, editors, 7th Asia-Pacific Conference
on Conceptual Modelling (APCCM 2010), CRPIT. ACS, 2010.
Abstract: In this paper we extend the preliminary work developed
elsewhere and investigate how to characterise many aspects of the compliance
problem in business process modeling. We first define a formal and
conceptually rich language able to represent, and reason about, chains of
reparational obligations of various types. Second, we devise a mechanism for
normalising a system of legal norms. Third, we specify a suitable language
for business process modeling able to automate and optimise business
procedures and to embed normative constraints. Fourth, we develop an
algorithm for compliance checking and discuss some computational issues
regarding the possibility of checking compliance runtime or of enforcing it
at design time.
 
- Guido Governatori and Antonino Rotolo.
-
On the complexity of temporal defeasible logic.
In Thomas Meyer and Eugenia Ternovska, editors, 13 International Workshop
on Non-Monotonic Reasoning (NMR 2010), CEUR Workshop Proceedings, 2010.
Abstract: In this paper we investigate the complexity of temporal
defeasible logic, and we propose an efficient algorithm to compute the
extension of a temporalised defeasible theory. We motivate the logic showing
how it can be used to model deadlines.
 
- Guido Governatori and Antonino Rotolo.
-
Norm
compliance in business process modeling.
In Mike Dean, John Hall, Antonino Rotolo, and Said Tabet, editors, RuleML
2010: 4th International Web Rule Symposium, number 6403 in LNCS, pages
194-209, Berlin, 2010. Springer. Copyrigth © 2010 Springer.
Abstract: We investigate the concept of norm compliance in
business process modeling. In particular we propose an extension of Formal
Contract Logic (FCL), a combination of defeasible logic and a logic of
violation, with a richer deontic language capable of capture many different
facets of normative requirements. The resulting logic, called Process
Compliance Logic (PCL), is able to capture both semantic compliance and
structural compliance. This paper focuses on structural compliance, that is
we show how PCL can capture obligations concerning the structure of a
business process.
 
- Guido Governatori and Rotolo Antonino.
-
Justice delayed is
justice denied: Logics for a temporal account of reparations and legal
compliance.
In João Leite, Paolo Torroni, Thomas Ågotnes, Guido Boella, and Leon van der Torre, editors, CLIMA XII, 12th International Workshop on
Computational Logic and Multi-Agent Sytems, number LNCS. Springer, 2011,
Copyrigth © 2011 Springer.
Abstract: In this paper we extend the logic of violation proposed
by Governatori and Rotolo with time, more precisely, we temporalise that
logic. The resulting system allows us to capture many subtleties of the
concept of legal compliance. In particular, the formal characterisation of
compliance can handle different types of legal obligation and different
temporal constraints over them. The logic is also able to represent, and
reason about, chains of reparative obligations, since in many cases the
fulfillment of these types of obligation still amount to legally acceptable
situations.
 
- Guido Governatori, Antonino
Rotolo and Vineet Padmanabhan.
- The
Cost of Social Agents. In 5th International Conference on
Autonomous Agents and Multi-Agent Systems (AAMAS06), ACM Press,
2006. Copyright © 2006 ACM.
Abstract: In this paper we follow the BOID (Belief,
Obligation, Intention, Desire) architecture to describe agents and
agent types in Defeasible Logic. We argue that the introduction of
obligations can provide a new reading of the concepts of intention and
intentionality. Then we examine the notion of social agent (i.e., an
agent where obligations prevail over intentions) and discuss some
computational and philosophical issues related to it. We show that
the notion of social agent either requires more complex computations
or has some philosophical drawbacks.
 
-
Guido Governatori, Antonino Rotolo, Régis Riveret, Monica Palmirani and Giovanni Sartor.
-
Variations of Temporal Defeasible Logic for Modelling Norm Modifications.
In Radboud Winkels, editor,
Proceedings of 11th International Conference on Artificial Intelligence and Law, 155-159. ACM Press, New York, 2007.
Copyright © 2007 ACM
Abstract: This paper proposes some variants of Temporal Defeasible Logic (TDL) to reason about normative modifications. These variants make it possible to differentiate cases in which, for example, modifications at some time change legal rules but their conclusions persist afterwards from cases where also their conclusions are blocked.
- Guido Governatori, Antonino Rotolo, and Rossella
Rubino.
-
Implementing temporal defeasible logic for modeling legal reasoning.
In 3rd Juris-Informatics Workshop (Jurisin 2009), LNAI, Berlin,
2010. Springer, Copyright © 2010 Springer.
Abstract: In this paper we briefly present an efficient
implementation of temporal defeasible logic, and we argue that it can be used
to efficiently capture the the legal concepts of persistence, retroactivity
and periodicity. In particular, we illustrate how the system works with a
real life example of a regulation.
 
- Guido Governatori, Antonino Rotolo, and
Giovanni Sartor.
-
Temporalised normative positions in defeasible
logic.
In Anne Gardner, editor, Procedings of the 10th International Conference
on Artificial Intelligence and Law, pages 25-34. ACM Press, 6-10 June
2005, Copyright © 2005 ACM.
Abstract:We propose a computationally oriented non-monotonic
multi-modal logic arising from the combination of temporalised agency and
temporalised normative positions. We argue about the defeasible nature of
these notions and then we show how to represent and reason with them in the
setting of Defeasible Logic.
 
- Guido Governatori and Shazia Sadiq.
-
The journey to business process
compliance.
In Jorge Cardoso and Wil van der Aalst, editors, Handbook of Research on
BPM, IGI Global, 2009.
Abstract: It is a typical scenario that many organisations have
their business processes specified independently of their business
obligations (which includes contractual obligations to business partners, as
well as obligations a business has to fulfil against regulations and industry
standards). This is because of the lack of guidelines and tools that
facilitate derivation of processes from contracts but also because of the
traditional mindset of treating contracts separately from business processes.
This chapter will provide a solution to one specific problem that arises from
this situation, namely the lack of mechanisms to check whether business
processes are compliant with business contracts. The chapter begins by
defining the space for business process compliance and the eco-system for
ensuring that process are compliant. The key point is that compliance is a
relationship between two sets of specifications: the specifications for
executing a business process and the specifications regulating a business.
The central part of the chapter focuses on a logic based formalism for
describing both the semantics of normative specifications and the semantics
of compliance checking procedures.
 
- Guido Governatori and Giovanni Sartor.
-
Burdens
of proof in monological argumentation.
In Radboud Winkels, editor, Legal Knowledge and Information Systems JURIX
2010: The Twenty-Third Annual Conference, Frontiers in Artificial
Intelligence and Applications, Amsterdam, 2010. IOS Press.
Abstract: We shall argue that burdens of proof are relevant also
to monological reasoning, i.e., for deriving the conclusions of a
knowledge-base allowing for conflicting arguments. Reasoning with burdens of
proof can provide a useful extension of current argument-based non-monotonic
logics, at least a different perspective on them. Firstly we shall provide an
objective characterisation of burdens of proof, assuming that burdens
concerns rule antecedents (literals in the body of rules), rather than
agents. Secondly, we shall analyse the conditions for a burden to be
satisfied, by considering credulous or skeptical derivability of the
concerned antecedent or of its complement. Finally, we shall develop a method
for developing inferences out of a knowledge base merging rules and proof
burdens in the framework of defeasible logic.
 
- Guido Governatori and Andrew Stranieri.
-
Towards the application of association rules
for defeasible rules discovery.
In Bart Verheij, Arno Lodder, Ronald P. Loui, and Antoniette J. Muntjerwerff,
editors, Legal Knowledge and Information Systems, pages 63-75,
Amsterdam, 2001. JURIX, IOS Press.
Abstract:In this paper we investigate the feasibility of
Knowledge Discovery from Database (KDD) in order to facilitate the discovery
of defeasible rules that represent the ratio decidendi underpinning legal
decision making. Moreover we will argue in favour of Defeasible Logic as the
appropriate formal system in which the extracted principles should be
encoded.
 
- Guido Governatori and Duy~Hoang Pham.
-
A
defeasible logic for modelling policy-based intentions and motivational
attitudes.
International Journal of Business Process Integration and
Management, 5(4), 2009.
Abstract: We introduce the DR-CONTRACT architecture to represent
and reason on e-Contracts. The architecture extends the DR-device
architecture by a deontic defeasible logic of violation. We motivate the
choice for the logic and we show how to extend RuleML to capture the notions
relevant to describe e-contracts for a monitoring perspective in Defeasible
Logic.
 
- Guido Governatori, Subhasis Thakur, and Duy Hoang
Pham.
-
A
compliance model of trust.
In Enrico Francesconi, Giovani Sartor, and Daniela Tiscornia, editors,
Legal Knowledge and Information Systems (Jurix 2008),
Frontieres in Artificial Intelligence and Applications 189, pages
118-127. IOS Press, 2008.
Abstract: We present a model of past interaction trust model
based on compliance of expected behaviours.
 
- Benjamin Johnston and Guido Governatori.
-
Induction of defeasible logic theories
in the legal domain.
In Giovanni Sartor, editor, Procedings of the 9th International
Conference on Artificial Intelligence and Law, pages 204-213. IAAIL, ACM
Press, 2003. Copyright
© 2003 ACM.
Abstract:The market for intelligent legal information systems
remains relatively untapped and while this might be interpreted as an
indication that it is simply impossible to produce a system that satisfies
the needs of the legal community, an analysis of previous attempts at
producing such systems reveals a common set of deficiencies that in-part
explain why there have been no overwhelming successes to date. Defeasible
logic, a logic with proven successes at representing legal knowledge, seems
to overcome many of these deficiencies and is a promising approach to
representing legal knowledge. Unfortunately, an immediate application of
technology to the challenges in this domain is an expensive and
computationally intractable problem. So, in light of the benefits, we seek to
find a practical algorithm that uses heuristics to discover an approximate
solution. As an outcome of this work, we have developed an algorithm that
integrates defeasible logic into a decision support system by automatically
deriving its knowledge from databases of precedents. Experiments with the new
algorithm are very promising - delivering results comparable to and
exceeding other approaches.
 
- Vineet Padmanabhan, Guido Governatori,
Shazia Sadiq, Robert Colomb and Antonino Rotolo.
-
Process Modelling: The Deontic Way.
In Markus Stumptner, Sven Hartmann
and Yasushi Kiyoki, editors, Database Technology
2006, number 53 in Conference Research and Practice of Information
Technology. Australian Computer Science Association, ACS,
16-19 January 2006. Copyright © 2006
ACS.
Abstract:Current enterprise systems rely heavily on the modelling and
enactment of business processes. One of the key criteria for a
business process is to represent not just the behaviours of the
participants but also how the contractual relationships among them
evolve over the course of an interaction.
In this paper we provide a framework in which one can define policies/
business rules using deontic assignments to represent the
contractual relationships.
To achieve this end we use a combination of deontic/normative concepts
like proclamation, directed obligation and
direct action to account for a deontic theory of commitment
which in turn can be used to model business processes in their
organisational settings. In this way we view a business process
as a social interaction process for the purpose of doing
business. Further, we show how to extend the i* framework, a
well known organisational modelling technique, so as to accommodate
our notion of deontic dependency.
 
- Monica Palmirani, Guido Governatori, and Giuseppe
Contissa.
-
Temporal
dimensions in rules modelling.
In Radboud Winkels, editor, Legal Knowledge and Information Systems JURIX
2010: The Twenty-Third Annual Conference, Frontiers in Artificial
Intelligence and Applications, Amsterdam, 2010. IOS Press.
Abstract: Typically legal reasoning involves multiple temporal
dimensions. The contribution of this work is to extend LKIF-rules (LKIF is a
proposed mark-up language designed for legal documents and legal knowledge in
ESTRELLA Project [3]) with temporal dimensions. We propose an XML-schema to
model the various aspects of the temporal dimensions in legal domain, and we
discuss the design choices. We illustrate the use of the temporal dimensions
in rules with the help of real life examples.
 
- Monica Palmirani, Guido Governatori, and Contissa
Giuseppe.
-
Modelling
temporal legal rules.
In Tom van Engers, editor, Proceedings of the 13th International
Conference on Artificial Intelligence and Law (ICAIL 2011). ACM Press,
2011. Copyrigth © 2011 ACM Press.
Abstract: Legal reasoning involves multiple temporal dimensions
but the existing state of the art of legal representation languages does not
allow us to easily combine expressiveness, performance and legal reasoning
requirements. Moreover we also aim at the combination of legal temporal
reasoning with the defeasible logic approach, maintaining a computable
complexity. The contribution of this work is to extend LKIF-rules with
temporal dimensions and defeasible tools, extending our previous work.
 
-
Régis Riveret, Antonino Rotolo and Guido Governatori.
-
Interaction between Normative Systems and Cognitive agents in
Temporal Modal Defeasible Logic. In Guido Boella, Leon van der
Torre and Harko Verhagen, editors, Normative Multi-agent
Systems. Dagstuhl Seminar Proceedings 7122. Internationales
Begegnungs- und Forschungszentrum fuer Informatik (IBFI), Schloss
Dagstuhl, Germany, Dagstuhl, Germany, 2007.
Abstract: While some recent frameworks on cognitive agents
addressed the combination of mental attitudes with deontic concepts,
they commonly ignore the representation of time. We propose in this
paper a variant of Temporal Modal Defeasible Logic to deal in
particular with temporal intervals.
 
-
Bram Roth, Régis Riveret, Antonino Rotolo and Guido Governatori.
-
Strategic Argumentation: A Game Theoretical Investigation.
In Radboud Winkels, editor,
Proceedings of 11th International Conference on Artificial Intelligence and Law, pp. 81-90. ACM Press, New York, 2007.
Copyright © 2007 ACM
Abstract: Argumentation is modelled as a game where the payoffs are measured in terms of the probability that the claimed conclusion is, or is not, defeasibly provable, given a history of arguments that have actually been exchanged, and given the probability of the factual premises. The probability of a conclusion is calculated using a standard variant of Defeasible Logic, in combination with standard probability calculus. It is a new element of the present approach that the exchange of arguments is analysed with game theoretical tools, yielding a prescriptive and to some extent even predictive account of the actual course of play. A brief comparison with existing argument-based dialogue approaches confirms that such a prescriptive account of the actual argumentation has been almost lacking in the approaches proposed so far.
- Miao Wang and Guido Governatori.
- A Logic
Framework of Normative-based Contract Management. Formal Methods in
Electronic Commerce 2007. Stanford University, Palo Alto, CA. June 4,
2007.
Abstract: We explore of the feasibility of the
computationally oriented institutional agency framework proposed by
Governatori and Rotolo testing it against an industrial strength scenario. In
particular we show how to encode in defeasible logic the dispute resolution
policy described in Article 67 of FIDIC.