A structured argumentation framework for detaching conditional obligations

We present a general formal argumentation system for dealing with the detachment of conditional obligations. Given a set of facts, constraints, and conditional obligations, we answer the question whether an unconditional obligation is detachable by considering reasons for and against its detachment. For the evaluation of arguments in favor of detaching obligations we use a Dung-style argumentation-theoretical semantics. We illustrate the modularity of the general framework by considering some extensions, and we compare the framework to some related approaches from the literature.Comment: This is our submission to DEON 2016, including the technical appendi

Obligation, Free Choice, And The Logic Of Weakest Permissions

We introduce a new understanding of deontic modals that we call obligations as weakest permissions. We argue for its philosophical plausibility, study its expressive power in neighborhood models, provide a complete Hilbert-style axiom system for it and show that it can be extended and applied to practical norms in decision and game theory

A Social Pragmatic View on the Concept of Normative Consistency

The programmatic statement put forward in von Wright's last works on deontic logic introduces the perspective of logical pragmatics, which has been formally explicated here and extended so to include the role of norm-recipient as well as the role of norm-giver. Using the translation function from the language of deontic logic to the language of set-theoretical approach, the connection has been established between the deontic postulates, on one side, and the perfection properties of the norm-set and the counter-set, on the other side. In the study of conditions of rational norm-related activities it has been shown that diverse dynamic second-order norms related to the concept of the consistency norm-system hold: -- the norm-giver ought to restore ``classical'' consistency by revising an inconsistent system, -- the norm-recipient ought to preserve an inconsistent system by revision of its logic so that inconsistency does not imply destruction of the system. Dialetheic deontic logic of Priest is a suitable logic for the purpose since it preserves other perfection properties of the system

Extended static checking by calculation using the pointfree transform

The pointfree transform offers to the predicate calculus what the La- place transform offers to the differential/integral calculus: the possibility of chang- ing the underlying mathematical space so as to enable agile algebraic calculation. This paper addresses the foundations of the transform and its application to a calculational approach to extended static checking (ESC) in the context of ab- stract modeling. In particular, a calculus is given whose rules help in breaking the complexity of the proof obligations involved in static checking arguments. The close connection between such calculus and that of weakest pre-conditions makes it possible to use the latter in ESC proof obligation discharge, where point- free notation is again used, this time to calculate with invariant properties to be maintained. A connection with the “everything is a relation” lemma of Alloy is estab- lished, showing how close to each other the pointfree and Alloy notations are. The main advantage of this connection is that of complementing pen-and-paper pointfree calculations with model checking support wherever validating sizable abstract models.Fundação para a Ciência e a Tecnologia (FCT

The Bad Man and the Good Lawyer: A Centennial Essay on Holmes\u27s \u3ci\u3eThe Path of the Law\u3c/i\u3e

Although Justice Holmes did not much enjoy listening to speeches (he once wondered what makes the world throng to hear loose-fibred and coarse-grained men drool ), he had a remarkable gift for writing them. Holmes\u27s 1920 Collected Legal Papers includes a dozen speeches and addresses, all delivered to student audiences or lawyers\u27 associations, and there are unexpected pleasures to be found in every one. He had published all but four in a previous book of speeches, where he described them as chance utterances of faith and doubt.., for a few friends who will care to keep them. \u27 Among the four he omitted from his compendium of speeches are his only surviving full length addresses, Law in Science and Science in Law and The Path of the Law. These, Mark Howe observes, evidently seemed to Holmes to be something more significant than \u27chance utterances of faith and doubt. \u2

Security Policy Consistency

With the advent of wide security platforms able to express simultaneously all the policies comprising an organization's global security policy, the problem of inconsistencies within security policies become harder and more relevant. We have defined a tool based on the CHR language which is able to detect several types of inconsistencies within and between security policies and other specifications, namely workflow specifications. Although the problem of security conflicts has been addressed by several authors, to our knowledge none has addressed the general problem of security inconsistencies, on its several definitions and target specifications.Comment: To appear in the first CL2000 workshop on Rule-Based Constraint Reasoning and Programmin

The intuitionistic fragment of computability logic at the propositional level

This paper presents a soundness and completeness proof for propositional intuitionistic calculus with respect to the semantics of computability logic. The latter interprets formulas as interactive computational problems, formalized as games between a machine and its environment. Intuitionistic implication is understood as algorithmic reduction in the weakest possible -- and hence most natural -- sense, disjunction and conjunction as deterministic-choice combinations of problems (disjunction = machine's choice, conjunction = environment's choice), and "absurd" as a computational problem of universal strength. See http://www.cis.upenn.edu/~giorgi/cl.html for a comprehensive online source on computability logic

Language, Law, and Logic: Plain Legal Drafting for the Electronic Age

The achievement of current demands for clearer legal drafting in the United States (New York, 1973 and President\u27s Executive Order, 1978) and Great Britain (Renton Report, 1975) can be aided by applying modern logic to improve the language of the law. In considering how the expression of legal norms can be clarified by using some formal language techniques, particular attention will be given to alternatives for dealing with problems of inadvertent imprecision in current legal drafting, alternatives that facilitate human understanding as well as enhance the possibilities for analysis by computer. A brief sketch of the imprecision of the expression of legal norms will help place in context the discussion of this L-trio: language, law, and logic. This imprecision can be categorized into two types of uncertainty: the uncertainty that results from what is omitted in the writing and the uncertainty that results from what is written. Both of these types of uncertainty may be deliberate by the drafter of the document, or they may occur inadvertently. Here, attention is being focused on the inadvertent written uncertainties