Статті в журналах з теми "Semantics Formalisation"

Existing semantic formalisations of the Intel-x86 architecture cover only a small fragment of its available features that are relevant for the consistency semantics of multi-threaded programs as well as the persistency semantics of programs interfacing with non-volatile memory. We extend these formalisations to cover: (1) non-temporal writes, which provide higher performance and are used to ensure that updates are flushed to memory; (2) reads and writes to other Intel-x86 memory types, namely uncacheable, write-combined, and write-through; as well as (3) the interaction between these features. We develop our formal model in both operational and declarative styles, and prove that the two characterisations are equivalent. We have empirically validated our formalisation of the consistency semantics of these additional features and their subtle interactions by extensive testing on different Intel-x86 implementations.

AbstractWe present a semantic framework for the deductive verification of hybrid systems with Isabelle/HOL. It supports reasoning about the temporal evolutions of hybrid programs in the style of differential dynamic logic modelled by flows or invariant sets for vector fields. We introduce the semantic foundations of this framework and summarise their Isabelle formalisation as well as the resulting verification components. A series of simple examples shows our approach at work.

In Japanese, as for many other languages, quantification of countable nouns is realized with numeral phrases, consisting of the numeral and the c1assifier. Each noun has a restricted set of possible c1assifiers from an inventory of approximately 100. The association between noun and classifier is threefold: It can be of either the lexical, semantic, or morphological type. This article proposes a formalization of the numeral phrase-noun association in order to analyse them with a syntactic-semantic parser. The present work is part of a larger research project on the formal syntax and semantics of Japanese numeral constructions.

AbstractThe worker/wrapper transformation is a general technique for improving the performance of recursive programs by changing their types. The previous formalisation (A. Gill & G. Hutton, J. Funct. Program., vol. 19, 2009, pp. 227–251) was based upon a simple fixed-point semantics of recursion. In this paper, we develop a more structured approach, based upon initial-algebra semantics. In particular, we show how the worker/wrapper transformation can be applied to programs defined using the structured pattern of recursion captured by fold operators, and illustrate our new technique with a number of examples.

We propose a mathematical semantics for event-based architectures that serves two main purposes: to characterise the modularisation properties that result from the algebraic structures induced on systems by this discipline of coordination; and to further validate and extend the categorical approach to architectural modelling that we have been building around the language CommUnity with the ‘implicit invocation’, also known as ‘publish/subscribe’ architectural style. We then use this formalisation to bring together synchronous and asynchronous interactions within the same modelling approach. We see this effort as a first step towards a form of engineering of architectural styles. Our approach adopts transition systems extended with events as a mathematical model of implicit invocation, and a family of logics that support abstract levels of modelling.

AbstractCategorical compositional distributional semantics is a model of natural language; it combines the statistical vector space models of words with the compositional models of grammar. We formalise in this model the generalised quantifier theory of natural language, due to Barwise and Cooper. The underlying setting is a compact closed category with bialgebras. We start from a generative grammar formalisation and develop an abstract categorical compositional semantics for it, and then instantiate the abstract setting to sets and relations and to finite-dimensional vector spaces and linear maps. We prove the equivalence of the relational instantiation to the truth theoretic semantics of generalised quantifiers. The vector space instantiation formalises the statistical usages of words and enables us to, for the first time, reason about quantified phrases and sentences compositionally in distributional semantics.

The concept of form and its derivations belong to the most important concepts of Antiquity and Middle Ages. Modern formal approaches in logic, semantics etc. depend on this problematics, rarely exposing it to scientific scrutiny. The article deals with a way medieval discussions on form and essence are reflected in contemporary approaches to formalisation, resulting in the confrontation between substantialist and constructivist paradigms.

This article elaborates on Christopher Norris's claim that certain aspects of Derrida's work are amenable to formalisation in modal-logical terms. Norris contends that any adequate analysis of the logic behind Derrida's work must provide an account of the notions of possibility, necessity, and necessary possibility, particularly as they are related to Derrida's notion of iterability. This article examines the further hypothesis that Derrida's understanding of modality, according to which possibilities must be accounted for even if they are never realised, might even better be described in terms of possible worlds. In possible-worlds semantics, the conceptual meaning of a statement is constituted by the set of alternative contexts in which that statement is true. This article argues, however, that possible-worlds semantics would be unthinkable without the experience that one referent can be substituted for another. The possibility of this experience is best described in Derridean terms. Read through Derrida's thought of the trace, the properly semantic substitutions (of names in view of a thing and of things in view of a concept) may come to be seen as dependent on the substitution of the thing for itself; on what Derrida calls ‘the substitution of the unique for the unique’.

AbstractThis paper studies the relation between two recent extensions of propositional Equilibrium Logic, a well-known logical characterisation of Answer Set Programming. In particular, we show how Temporal Equilibrium Logic, which introduces modal operators as those typically handled in Linear-Time Temporal Logic (LTL), can be encoded into Infinitary Equilibrium Logic, a recent formalisation that allows the use of infinite conjunctions and disjunctions. We prove the correctness of this encoding and, as an application, we further use it to show that the semantics of the temporal logic programming formalism called TEMPLOG is subsumed by Temporal Equilibrium Logic.

Despite extensive research both on the theoretical and practical fronts, formalising, reasoning about, and implementing languages with variable binding is still a daunting endeavour – repetitive boilerplate and the overly complicated metatheory of capture-avoiding substitution often get in the way of progressing on to the actually interesting properties of a language. Existing developments offer some relief, however at the expense of inconvenient and error-prone term encodings and lack of formal foundations. We present a mathematically-inspired language-formalisation framework implemented in Agda. The system translates the description of a syntax signature with variable-binding operators into an intrinsically-encoded, inductive data type equipped with syntactic operations such as weakening and substitution, along with their correctness properties. The generated metatheory further incorporates metavariables and their associated operation of metasubstitution, which enables second-order equational/rewriting reasoning. The underlying mathematical foundation of the framework – initial algebra semantics – derives compositional interpretations of languages into their models satisfying the semantic substitution lemma by construction.

AbstractProlog's very useful expressive power is not captured by traditional logic programming semantics, due mainly to the cut and goal and clause order. Several alternative semantics have been put forward, exposing operational details of the computation state. We propose instead to redesign Prolog around structured alternatives to the cut and clauses, keeping the expressive power and computation model but with a compositional denotational semantics over much simpler states—just variable bindings. This considerably eases reasoning about programs, by programmers and tools such as a partial evaluator, with safe unfolding of calls through predicate definitions. Anif-then-elseacross clauses replaces most uses of the cut, but the cut's full power is achieved by anuntilconstruct. Disjunction, conjunction anduntil, along with unification, are the primitive goal types with a compositional semantics yielding sequences of variable-binding solutions. This extends to programs via the usual technique of a least fixpoint construction. A simple interpreter for Prolog in the alternative language, and a definition ofuntilin Prolog, establish the identical expressive power of the two languages. Many useful control constructs are derivable from the primitives, and the semantic framework illuminates the discussion of alternative ones. The formalisation rests on a term language with variable abstraction as in the λ-calculus. A clause is an abstraction on the call arguments, a continuation, and the local variables. It can be inclusive or exclusive, expressing a local case bound to a continuation by either a disjunction or anif-then-else. Clauses are open definitions, composed (and closed) with simple functional application β-reduction). This paves the way for a simple account of flexible module composition mechanisms.Cube, a concrete language with the exposed principles, has been implemented on top of a Prolog engine and successfully used to build large real-world applications.

Programming or scripting languages used in real-world systems are seldom designed with a formal semantics in mind from the outset. Therefore, developing well-founded analysis tools for these systems requires reverse-engineering a formal semantics as a first step. This can take months or years of effort. Can we (at least partially) automate this process? Though desirable, automatically reverse-engineering semantics rules from an implementation is very challenging, as found by Krishnamurthi, Lerner and Elberty. In this paper, we highlight that scaling methods with the size of the language is very difficult due to state space explosion, so we propose to learn semantics incrementally. We give a formalisation of Krishnamurthi et al.'s desugaring learning framework in order to clarify the assumptions necessary for an incremental learning algorithm to be feasible. We show that this reformulation allows us to extend the search space and express rules that Krishnamurthi et al. described as challenging, while still retaining feasibility. We evaluate enumerative synthesis as a baseline algorithm, and demonstrate that, with our reformulation of the problem, it is possible to learn correct desugaring rules for the example source and core languages proposed by Krishnamurthi et al., in most cases identical to the intended rules. In addition, with user guidance, our system was able to synthesize rules for desugaring list comprehensions and try/catch/finally constructs.

Multiple logic-based reconstructions of conceptual data modelling languages such as EER, UML Class Diagrams, and ORM exist. They mainly cover various fragments of the languages and none are formalised such that the logic applies simultaneously for all three modelling language families as unifying mechanism. This hampers interchangeability, interoperability, and tooling support. In addition, due to the lack of a systematic design process of the logic used for the formalisation, hidden choices permeate the formalisations that have rendered them incompatible. We aim to address these problems, first, by structuring the logic design process in a methodological way. We generalise and extend the DSL design process to apply to logic language design more generally and, in particular, by incorporating an ontological analysis of language features in the process. Second, we specify minimal logic profiles availing of this extended process, including the ontological commitments embedded in the languages, of evidence gathered of language feature usage, and of computational complexity insights from Description Logics (DL). The profiles characterise the essential logic structure needed to handle the semantics of conceptual models, therewith enabling the development of interoperability tools. There is no known DL language that matches exactly the features of thoseprofiles and the common core is small (in the tractable DL ALNI). Although hardly any inconsistencies can be derived with the profiles, it is promising for scalable runtime use of conceptual data models.

В статье обсуждаются два решения, предложенные (Э. Кешетом и Ш. Чжу) для объяснения «дально-действия» (tele-scoping) - избирательной способности именных групп с универсальной семантикой связывать местоимения через границу предложения в зависимости от риторической структуры дискурса. Исходя из их сильных и слабых сторон мы формулируем требования к формализации, в которой семантический вклад самих риторических отношений состоит в том, что они задействуют различные операции обновления информации в дискурсе. В качестве первого шага в этом направлении предложено различать две операции обновления, одна из которых применяется в случаях «дально-действия». The paper makes a case for encoding different types of update operations directly in the rhetorical structure of discourse. First, I discuss two solutions for the puzzle of tele-scoping, i.e. the conditional ability of universal DPs to bind a pronoun across a sentential boundary, proposed by Ezra Keshet and by Shensheng Zhu. Basing on their relative advantages and disadvantages, I outline an agenda for a formalisation which, instead of linking discourse structure to some features of the interpretative pipeline, directly encodes different types of update into the interpretation of rhetorical relations. The degree to which this direction is worth pursuing is illustrated for tele-scoping, whose difference from cases where cross-sentential binding is impossible is argued to be that the latter use the “oblivious” type of update, which cannot preserve the values of universally quantified variables.

This paper discusses knowledge of opposites. In particular, attention is given to the linguistic notion of antonymy and how it represents oppositional relations that are commonly found in perception. The paper draws upon the long history of work on the formalisation of antonymy in linguistics and formal semantics, and also upon work on the perception of opposites in psychology, and an assessment is made of the main approaches. Treatments of these phenomena in linguistics and psychology posit that the principles of minimal difference and invariance are centrally important. It will be suggested that the standard approach employing meaning postulates fails to capture the relevant notion of antonymy, in part because it is not informed by these principles, and in part due to a number of other problems with this kind of approach, many of which may be overcome by building in the central principles from the beginning. The paper also discusses the issue of whether we can know that opposites necessarily exclude each other and, if so, how. This issue is intertwined with what is known as the colour incompatibility problem that Wittgenstein wrangled with at various times during his life. The paper assesses various solutions to these problems including an approach that was first put forward by Jerrold J. Katz. The relation between this approach and the theory of determinables and determinates is also examined. A further development upon this approach is proposed and then applied to the case of the formalisation of antonymy. It is argued that this approach avoids the problems suffered by the main approaches discussed earlier in the paper.

The Pi family of reversible programming languages for boolean circuits is presented as a syntax of combinators witnessing type isomorphisms of algebraic data types. In this paper, we give a denotational semantics for this language, using weak groupoids à la Homotopy Type Theory, and show how to derive an equational theory for it, presented by 2-combinators witnessing equivalences of type isomorphisms. We establish a correspondence between the syntactic groupoid of the language and a formally presented univalent subuniverse of finite types. The correspondence relates 1-combinators to 1-paths, and 2-combinators to 2-paths in the universe, which is shown to be sound and complete for both levels, forming an equivalence of groupoids. We use this to establish a Curry-Howard-Lambek correspondence between Reversible Logic, Reversible Programming Languages, and Symmetric Rig Groupoids, by showing that the syntax of Pi is presented by the free symmetric rig groupoid, given by finite sets and bijections. Using the formalisation of our results, we perform normalisation-by-evaluation, verification and synthesis of reversible logic gates, motivated by examples from quantum computing. We also show how to reason about and transfer theorems between different representations of reversible circuits.

The introduction of first-class type classes in the Coq system calls for a re-examination of the basic interfaces used for mathematical formalisation in type theory. We present a new set of type classes for mathematics and take full advantage of their unique features to make practical a particularly flexible approach that was formerly thought to be unfeasible. Thus, we address traditional proof engineering challenges as well as new ones resulting from our ambition to build upon this development a library of constructive analysis in which any abstraction penalties inhibiting efficient computation are reduced to a minimum.The basis of our development consists of type classes representing a standard algebraic hierarchy, as well as portions of category theory and universal algebra. On this foundation, we build a set of mathematically sound abstract interfaces for different kinds of numbers, succinctly expressed using categorical language and universal algebra constructions. Strategic use of type classes lets us support these high-level theory-friendly definitions, while still enabling efficient implementations unhindered by gratuitous indirection, conversion or projection.Algebra thrives on the interplay between syntax and semantics. The Prolog-like abilities of type class instance resolution allow us to conveniently define a quote function, thus facilitating the use of reflective techniques.

AbstractMajor advances have recently been made in merging language and vision representations. Most tasks considered so far have confined themselves to the processing of objects and lexicalised relations amongst objects (content words). We know, however, that humans (even pre-school children) can abstract over raw multimodal data to perform certain types of higher level reasoning, expressed in natural language byfunction words. A case in point is given by their ability to learn quantifiers, i.e. expressions likefew,someandall. From formal semantics and cognitive linguistics, we know that quantifiers are relations over sets which, as a simplification, we can see as proportions. For instance, inmost fish are red,mostencodes the proportion of fish which are red fish. In this paper, we study how well current neural network strategies model such relations. We propose a task where, given an image and a query expressed by an object–property pair, the system must return a quantifier expressing which proportions of the queried object have the queried property. Our contributions are twofold. First, we show that the best performance on this task involves coupling state-of-the-art attention mechanisms with a network architecture mirroring the logical structure assigned to quantifiers by classic linguistic formalisation. Second, we introduce a new balanced dataset of image scenarios associated with quantification queries, which we hope will foster further research in this area.

AbstractIntuitionistic logic formalises the foundational ideas of L.E.J. Brouwer’s mathematical programme of intuitionism. It is one of the earliest non-classical logics, and the difference between classical and intuitionistic logic may be interpreted to lie in the law of the excluded middle, which asserts that either a proposition is true or its negation is true. This principle is deemed unacceptable from the constructive point of view, in whose understanding the law means that there is an effective procedure to determine the truth of all propositions. This understanding of the distinction between the two logics supports the view that negation plays a vital role in the formulation of intuitionistic logic.Nonetheless, the formalisation of negation in intuitionistic logic has not been universally accepted, and many alternative accounts of negation have been proposed. Some seek to weaken or strengthen the negation, and others actively supporting negative inferences that are impossible with it.This thesis follows this tradition and investigates various aspects of negation in intuitionistic logic. Firstly, we look at a problem proposed by H. Ishihara, which asks how effectively one can conserve the deducibility of classical theorems into intuitionistic logic, by assuming atomic classes of non-constructive principles. The classes given in this section improve a previous class given by K. Ishii in two respects: (a) instead of a single class for the law of the excluded middle, two classes are given in terms of weaker principles, allowing a finer analysis and (b) the conservation now extends to a subsystem of intuitionistic logic called Glivenko’s logic. This section also discusses the extension of Ishihara’s problem to minimal logic.Secondly, we study the relationship between two frameworks for weak constructive negation, the approach of D. Vakarelov on one hand and the framework of subminimal negation by A. Colacito, D. de Jongh, and A. L. Vargas on the other hand. We capture a version of Vakarelov’s logic with the semantics of the latter framework, and clarify the relationship between the two semantics. This also provides proof-theoretic insights, which results in the formulation of a cut-free sequent calculus for the aforementioned system.Thirdly, we investigate the ways to unify the formalisations of some logics with contra-intuitionistic inferences. The enquiry concerns paraconsistent logics by R. Sylvan and A. B. Gordienko, as well as the logic of co-negation by G. Priest and of empirical negation by M. De and H. Omori. We take Sylvan’s system as basic, and formulate the frame conditions of the defining axioms of the other systems. The conditions are then used to obtain cut-free labelled sequent calculi for the systems.Finally, we consider L. Humberstone’s actuality operator for intuitionistic logic, which can be seen as the dualisation of a contra-intuitionistic negation. A compete axiomatisation of intuitionistic logic with actuality operator is given, and comparisons are made for some related operators.Abstract prepared by Satoru Niki.E-mail:Satoru.Niki@rub.de

Artifact systems are a novel paradigm for specifying and implementing business processes described in terms of interacting modules called artifacts. Artifacts consist of data and lifecycles, accounting respectively for the relational structure of the artifacts’ states and their possible evolutions over time. In this paper we put forward artifact-centric multi-agent systems, a novel formalisation of artifact systems in the context of multi-agent systems operating on them. Differently from the usual process-based models of services, we give a semantics that explicitly accounts for the data structures on which artifact systems are defined. We study the model checking problem for artifact-centric multi-agent systems against specifications expressed in a quantified version of temporal-epistemic logic expressing the knowledge of the agents in the exchange. We begin by noting that the problem is undecidable in general. We identify a noteworthy class of systems that admit bisimilar, finite abstractions. It follows that we can verify these systems by investigating their finite abstractions; we also show that the corresponding model checking problem is EXPSPACE-complete. We then introduce artifact-centric programs, compact and declarative representations of the programs governing both the artifact system and the agents. We show that, while these in principle generate infinite-state systems, under natural conditions their verification problem can be solved on finite abstractions that can be effectively computed from the programs. We exemplify the theoretical results here pursued through a mainstream procurement scenario from the artifact systems literature.

The last decade witnessed a surge of new research in pragmatics, fuelled by the emergence of new theoretical frameworks, an increased interest in the semantics-pragmatics interface, and the establishment of experimental pragmatics as a new research paradigm. Many of these developments concern the line of pragmatics which originated with the work of H. Paul Grice. Of new theoretical frameworks, we may mention different variants of optimality and game theoretic approaches, localist semantic theories of embedded implicatures, logical globalist formalisations of Gricean pragmatics, and multi-layered semantics for conventional implicatures. At the same time, research in older frameworks such as Neo-Gricean and Post-Gricean pragmatics continued, and new investigations of speech act and presupposition theory emerged. This development led to a diversification of theoretical approaches, a synthesis of which is desirable but not to be expected in the near future. This issue is intended as a contribution to the enhancement of mutual awareness and the discussion of each other’s results.

We provide an analysis of French clitic pronouns in multimodal categorial grammars. This analysis is a simplification of the one by Esther Kraak along the lines of Raffaela Bernardi and Richard Moot for quantifier scope. As expected from the categorial setting, our formalisation provides an easy way to compute semantic representations even when there are clitic climbing and control phenomena.

During various learning activities, teachers and students need to clarify, explore and share their understanding of reading materials. For doing this, they must make explicit the mental representation constructed during the reading process. In this article, we propose an approach combining semantic annotations and semantic networks as formal means for elicitation, structuring, formalisation, analysis and sharing of teachers’ and students’ understanding of textual materials that they are asked to read in learning tasks. In the proposed approach, teachers can create learning tasks, in which students are asked to semantically annotate a text by associating portions of it to resources described in a Knowledge Base (KB) in accordance with a provided ontology. New instances can be created by students or teachers in the KB during the annotation process. We show how semantic networks can be used to visualise extracts of the resulting KB, and to help people organise their comprehension of texts. In addition, teachers can assess student evolution by analysing the semantic networks that each one produces during the reading and annotation process. This approach is implemented by using our annotation tool, integrated with a digital repository and a virtual learning environment. An empirical evaluation of the benefits of the proposed approach in a literature case study confirms that it facilitates information extraction, sharing and analysis, contributing to leverage teaching and learning.

AbstractFirst-order formalisations are often preferred to propositional ones because they are thought to underwrite the validity of more arguments. We compare and contrast the ability of some well-known logics—these two in particular—to formally capture valid and invalid arguments. We show that there is a precise and important sense in which first-order logic does not improve on propositional logic in this respect. We also prove some generalisations and related results of philosophical interest. The rest of the article investigates the results’ philosophical significance. A first moral is that the correct way to state the oft-cited superiority of first-order logic vis-à-vis propositional logic is more nuanced than often thought. The second moral concerns semantic theory; the third logic’s use as a tool for discovery. A fourth and final moral is that second-order logic’s transcendence of first-order logic is greater than first-order logic’s transcendence of propositional logic.

This paper deals with a group of contemporary legal texts which have the form of statutes. The author describes the anaphoric relation between nominal groups (NG) constituted by an event-driven element and sentences which are linearly prior to these groups, the so-called antecedents. The analysis, founded on principles of syntax with a semantic basis, provides observations about restrictions in the formalisation of elements of the semantic base whose elements can be connected with the use of NG. The disclosure of elements of the content plan, excluding exceptions, entails a condensation which causes that categorical meanings that are the most intensely governed and communicatively relevant are fulfilled on the surface. The inability to reproduce the meaning of the “grammatical agent” causes that NG with a constitutive event-driven element are an indication of the depersonalisation attributed to legal texts. The repeatability of NG, mainly one- and two-component phrases, as well as their initial location in an utterance are factors depicting another feature of statutes: syntactic schematism. The author also demonstrates that the system of intratextual references is not the same in various variants of the Polish language. In the statute, as a genre of the legal language, its specific nature is already noticeable within one of the systematising units of the legal text, i.e. the article. The specific nature of the examined relation is conditioned by (1) the proper arrangement of structures connected with a network of references, and (2) the manner of their denotation. These features are the results of adherence to the editorial principles of legal texts.

The religious transition in the Late Viking Age examined on the basis of Harvey Whitehouse’s theory of religious modalityThe point of no return in the transition between pagan and Christian religious systems is pinpointed as the inscription on a rune stone erected between the two burial mounds at Jelling. Since the religious change did not take place exclusively in the Late Viking Age, the time frame of this article is restricted to before AD 1000. The main geographical area from which empirical data are available is loosely defined as that comprising present day Scandinavia and Northern Germany.The archaeological evidence employed by earlier scholars in examining the religious transition in this area falls mainly into three categories: burials, cult sites and the site of Jelling. The interpretation reached on the basis of these finds was that the transition from Paganism to Christianity occurred without conflict because the structure of the pagan cult was the same as that in the Christian Church. This interpretation appears somewhat unfounded in the archaeological record. By using Harvey Whitehouse’s theory of divergent modes of religiosity (DMR), the aim of this article is to gain a more detailed and consistent picture of the religious mode prior to the transition from Paganism to Christianity.In short, Harvey Whitehouse’s theory claims that all religiosity is either imagistic or doctrinal, depending on how the participants in various religions organise their rituals and how they create religious meaning.The imagistic mode is characterised by low frequency, high arousal (often violent) rituals where religious meaning is created by what Harvey Whitehouse calls spontaneous exegetical reflection. In combination, these activate the episodic memory when participating in religious activities. The participants in imagistic rituals often live in societies with a low degree of centralisation and often with weak or even no ritual leadership. This religious mode also has a small-scale and slow geographical spread because of the personal nature of the rituals.The doctrinal mode is characterised by high-frequency rituals with low arousal, where religious meaning is taught by logical, integrated narratives. In combination, these activate the semantic memory when participating in such rituals. This mode is found in societies with a high degree of centralisation and is carried by a strong religious leadership, making a large-scale and rapid spread possible.The DMR theory has 12 defining variables which have opposing qualities depending on the modality distinguishable in the archaeological record. The idea is to apply the DMR theory to selected archaeological sources consisting of the following find categories: burials, burial sites, central places and monumental burials.The first find category discussed is the burials and burial sites of the Late Viking Age. This category contains much information relevant to several variables in DMR. When specific combinations of weapons and equestrian grave goods, and special grave constructions, are considered, the evidence seems to suggest that, on a regional level, there are clear similarities between these types of burials, corresponding to the doctrinal modality. Based on an interpretation of similarities existing over a significant time period, it is assumed that a control of the narrative underlines the ritual objects employed. In contrast, the burial sites described in the case studies from the Late Viking Age seem to reflect a hierarchical organization of the burial sites and a distribution of the overall number of grave goods in the graves which shows traits resembling imagistic modality. Since the latter sites show a segmented heterogeneous distribution of grave goods, they are interpreted as an expression of a small-scale, exclusive religious burial system. This is also reflected in the gender and age distribution of the skeletal remains with a secure dating to the Late Viking Age. The material here clearly shows that a large proportion of the living population was denied access to the burial sites, and since almost all skeletal remains were found on burial sites, this is interpreted as corresponding to imagistic modality for the society as a whole.The central places are relevant because it is here we find the remains of cult buildings from the periods leading up to the Viking Age. The archaeological record reveals that there were specific buildings where different rituals were performed over a considerable period of time. The various objects found in the buildings, such as bracteates, gold foil figures and drinking vessels, are mentioned in the context of their religious interpretation. The conclusion reached is that the objects seem to undergo a degree of formalisation towards a more abstract expression, which I claim is based on a greater dependency on narratives in understanding and recognising the images depicted on the objects. This dependency on religious narratives corresponds to the doctrinal modality. On the other hand, the fact that these central places had such long periods of activity, and that they are located within the chieftains’ farmsteads, seems to indicate that the rituals performed within the buildings were not “public” in a broad sense, but were generally exclusive and thus an imagistic trait.The final archaeological source comprises the monumental long-ship burials dating from the Late Viking Age. An interpretation proposed by Tejrne Gansum, based on the evidence from the long-ship burial at Oseberg in Norway, claims that these burials were constructed as public events, where significant sacrifices of valuables, livestock and even people were performed on the ship like on the stage of a theatre. These burials are considered to be violent and to represent events which quite easily could activate episodic memory; they are therefore considered to be manifestations of imagistic modality.The two foreign written sources, the chronicle of Adam of Bremen and the travel accounts of Ibn Fadlan, were chosen because much of the information they contain can be verified by the archaeological record. Adam of Bremen’s account confirms that there were specific buildings where the cult and rituals were performed. The specific drinking and sacrificial rituals described in the text also correspond to evidence in the archaeological record. It is also noted that the frequency of these rituals was very low. In Ibn Fadlan’s travelogue, a supposed Viking ship burial is described. This source provides a large amount of information, not all of which, however, can be confirmed by the archaeological record. The verifiable information shows that the choice of sacrificial objects and the drinking rituals were consistent with Adam of Bremen’s chronicle. Apart from these observations, it is also noted that the spectators were not given specific information by the participants in the ritual, yet they still knew which actions were taking place inside the tent erected on the ship. What is described here seems to fit with imagistic modality.The conclusion reached in this article is that the structure of the pre-Christian religion was not identical to that of the Christian religion, but that there were significant similarities. These similarities are due to the fact that the nobility of the pre-Christian period made great use of religious narrative and were therefore accustomed to control and strong religious leadership indicative of doctrinal modality. The peaceful shift in religion is most likely due to the circumstance that it was the same nobility that erected cult houses in the Viking Age which were also responsible for the construction and ownership of the first wooden churches. Their willingness to change must have been based on personal sympathies towards the Christian message.Njal J. GeertzRingkøbing-Skjern Museum

AbstractIn this theoretical paper, we consider the notion of semantic competence and its relation to general language understanding—one of the most sough-after goals of Artificial Intelligence. We come back to three main accounts of competence involving (a) lexical knowledge; (b) truth-theoretic reference; and (c) causal chains in language use. We argue that all three are needed to reach a notion of meaning in artificial agents and suggest that they can be combined in a single formalisation, where competence develops from exposure to observable performance data. We introduce a theoretical framework which translates set theory into vector-space semantics by applying distributional techniques to a corpus of utterances associated with truth values. The resulting meaning space naturally satisfies the requirements of a causal theory of competence, but it can also be regarded as some ‘ideal’ model of the world, allowing for extensions and standard lexical relations to be retrieved.

AbstractWe compare the expressive power of three programming abstractions for user-defined computational effects: Plotkin and Pretnar’s effect handlers, Filinski’s monadic reflection, and delimited control. This comparison allows a precise discussion about the relative expressiveness of each programming abstraction. It also demonstrates the sensitivity of the relative expressiveness of user-defined effects to seemingly orthogonal language features. We present three calculi, one per abstraction, extending Levy’s call-by-push-value. For each calculus, we present syntax, operational semantics, a natural type-and-effect system, and, for effect handlers and monadic reflection, a set-theoretic denotational semantics. We establish their basic metatheoretic properties: safety, termination, and, where applicable, soundness and adequacy. Using Felleisen’s notion of a macro translation, we show that these abstractions can macro express each other, and show which translations preserve typeability. We use the adequate finitary set-theoretic denotational semantics for the monadic calculus to show that effect handlers cannot be macro expressed while preserving typeability either by monadic reflection or by delimited control. Our argument fails with simple changes to the type system such as polymorphism and inductive types. We supplement our development with a mechanised Abella formalisation.

AbstractCrispin Wright in his 1982 paper argues for strict finitism, a constructive standpoint that is more restrictive than intuitionism. In its appendix, he proposes models of strict finitistic arithmetic. They are tree-like structures, formed in his strict finitistic metatheory, of equations between numerals on which concrete arithmetical sentences are evaluated. As a first step towards classical formalisation of strict finitism, we propose their counterparts in the classical metatheory with one additional assumption, and then extract the propositional part of ‘strict finitistic logic’ from it and investigate. We will provide a sound and complete pair of a Kripke-style semantics and a sequent calculus, and compare with other logics. The logic lacks the law of excluded middle and Modus Ponens and is weaker than classical logic, but stronger than any proper intermediate logics in terms of theoremhood. In fact, all the other well-known classical theorems are found to be theorems. Finally, we will make an observation that models of this semantics can be seen as nodes of an intuitionistic model.

<p>Apt and van Emden have studied the semantics of logic programming by means of fixed point methods. From a model theoretic point of view, their formalisation is very nice. Least and greatest fixed points correspond to least and greatest Herbrand-models respectively.</p><p>Viewed operationally, there is an ugly asymmetry. The least fixed point expresses finite computability, but the greatest fixed point denotes negation by <em>trans</em>-finite failure, i.e. the underlying operator is not omega-continuous for decreasing chains in general.</p><p>We use the notion of finite computability inherent in Scott domains to build a domainlike construction (the cd-domain) that offers omega-continuity for increasing and decreasing chains equally. On this basis negation by finite failure is expressed in terms of a fixed point.</p><p>The fixed point semantics of Apt and van Emden is very abstract concerning the concept of substitution, although it is fundamental for any implementation. Hence it becomes quite tedious to prove the correctness of a concrete resolution algorithm. The fixed point semantics of this paper offers an intermediate step in this respect. Any commitments to specific resolution strategies are avoided, and the semantics may be the basis of sequential and parallel implementations equally. Simultaneously the set of substitution dataobjects is structured by a Scott information theoretic partial order, namely the cd-domain.</p>

AbstractDefinite descriptions are widely discussed in linguistics and formal semantics, but their formal treatment in logic is surprisingly modest. In this article we present a sound, complete, and cut-free tableau calculus $${\textbf{TC}}_{R_{\lambda }}$$ TC R λ for the logic $${\textbf{L}}_{R_{\lambda }}$$ L R λ being a formalisation of a Russell-style theory of definite descriptions with the iota-operator used to construct definite descriptions, the lambda-operator forming predicate-abstracts, and definite descriptions as genuine terms with a restricted right of residence. We show that in this setting we are able to overcome problems typical of Russell’s original theory, such as scoping difficulties or undesired inconsistencies. We prove the Craig interpolation property for the proposed theory, which, through the Beth definability property, allows us to check whether an individual constant from a signature has a definite description-counterpart under a given theory.

Amalgamation is a well-known concept for graph transformations that is used to model synchronised parallelism of rules with shared subrules and corresponding transformations. This concept is especially important for an adequate formalisation of the operational semantics of statecharts and other visual modelling languages, where typed attributed graphs are used for multiple rules with nested application conditions. However, the theory of amalgamation for the double-pushout approach has so far only been developed on a set-theoretical basis for pairs of standard graph rules without any application conditions.For this reason, in the current paper we present the theory of amalgamation for$\mathcal{M}$-adhesive categories, which form a slightly more general framework than (weak) adhesive HLR categories, for a bundle of rules with (nested) application conditions. The two main results are the Complement Rule Theorem, which shows how to construct a minimal complement rule for each subrule, and the Multi-Amalgamation Theorem, which generalises the well-known Parallelism and Amalgamation Theorems to the case of multiple synchronised parallelism. In order to apply the largest amalgamated rule, we use maximal matchings, which are computed according to the actual instance graph. The constructions are illustrated by a small but meaningful running example, while a more complex case study concerning the firing semantics of Petri nets is presented as an introductory example and to provide motivation.

Do two conventions of international environmental law necessarily endow the same word with the same meaning? A single counterexample is enough to answer in the negative: this is the case of the term “resource” in the United Nations Convention on the Law of the Sea (UNCLOS) and the Convention on Biological Diversity (CBD). Beyond this result, we tackle the questions, raised by the method of analysis implemented, about the semantics of legal texts, a source of interpretative flexibility but also of cognitive amalgamations and confusions of various types. A conceptual graph is associated with each proposition or sentence comprising the term “resource.” Some expressions, especially those of a deontic nature and noun phrases naming a group of interrelated entities or a fact, are encoded in nested graphs. The scope of a term is revealed by the neighbourhood of its uses. Neighbouring expressions, positioned along the paths of conceptual graphs, are ranked owing to their distance from the target expression. Then the neighbours the most contributing to the distributional meaning of the targets are classified in a coarse taxonomy, providing basic ontological traits to “resource” and related expressions in each convention. Although the two conventions rely on the same language, the weak overlap of their respective neighbourhoods of the term “resource” and associated expressions and their contrasted ontological anchorages highlight idiosyncratic meanings and, consequently, divergent orientations and understandings regarding the protection and conservation of resources, especially of living resources. Thus, the complexity of legal texts operates both in the gap between language semantics and cognitive understanding of the concepts used, and in the interpretative flexibility and opportunities for confusion that the texts offer but that the elementary operations of formalisation allow to deconstruct and clarify.

The GRAphe Fonctionnel de Commande Étapes Transitions (GRAFCET) is a powerful graphical modeling language for the pecification of controllers in discrete event systems.It uses expressions to express the conditions of transitions and conditional actions as well as the logical and arithmetic expressions assigned to stored actions. However, several research works has focused on the transformation of Grafcet specifications (including expressions) into control code for embedded systems. To make it easier to edit valid Grafcet models and generate code, it is necessary to propose a formalization of the Grafcet expression language permitting to validate its constructs and provide an appropriate semantics. For this, we propose a context-free grammar that generates the whole set of Grafcet expressions, by extending the usual grammars of logical and arithmetic expressions. We also propose a metamodel and an associated semantics of Grafcet expressions to facilitate the implementation of the Grafcet language. A parser of the expressions Grafcet emph G7Expr is then obtained thanks to the generator of parsers ANTLR, while the metamodel is implemented in the Eclipse EMF Model Driven Engineering (MDE) environment. The combination of the two tools makes it possible to analyze and automatically build Grafcet expressions when editing and synthesizing Grafcet models. Le GRAphe Fonctionnel de Commande Étapes Transitions (GRAFCET) est un puissant lan-gage de modélisation graphique pour la spécification de contrôleurs dans des systèmes à événe-ments discrets. Il fait usage des expressions pour exprimer les conditions de franchissement des transitions et des actions conditionnelles ainsi que les expressions logiques et arithmétiques assi-gnées aux actions stockées. Cependant, de nombreux travaux se sont penchés sur la transformation de spécifications Grafcet (y compris les expressions) en code de contrôle pour systèmes embar-qués. Pour faciliter l'édition de modèles Grafcet valides et la génération du code de contrôle, il est judicieux de proposer une formalisation du langage des expressions Grafcet, permettant de valider ses constructions et d'en pourvoir une sémantique appropriée. Pour cela, nous proposons une gram-maire hors-contexte qui génère tout l'ensemble des expressions Grafcet, en étendant les grammaires usuelles des expressions arithmétiques et logiques. Nous proposons également un métamodèle et une sémantique associée des expressions Grafcet pour faciliter la mise en oeuvre du langage Grafcet sous la forme d'un parseur des expressions Grafcet G7Expr obtenu grce au générateur d'analyseurs syntaxiques ANTLR, alors que le métamodèle est mis en oeuvre dans l'environnement d'Ingénie-rie Dirigée par les Modèles (IDM) Eclipse EMF. L'association des deux outils permet d'analyser et de construire automatiquement les expressions Grafcet lors de l'édition et la synthèse des modèles Grafcet.

AbstractDigital technologies are becoming more pervasive and industrial companies are exploiting them to enhance the potentialities related to Prognostics and Health Management (PHM). Indeed, PHM allows to evaluate the health state of the physical assets as well as to predict their future behaviour. To be effective in developing PHM programs, the most critical assets should be identified so to direct modelling efforts. Several techniques could be adopted to evaluate asset criticality; in industrial practice, criticality analysis is amongst the most utilised. Despite the advancement of artificial intelligence for data analysis and predictions, the criticality analysis, which is built upon both quantitative and qualitative data, has not been improved accordingly. It is the goal of this work to propose an ontological formalisation of a multi-attribute criticality analysis in order to i) fix the semantics behind the terms involved in the analysis, ii) standardize and uniform the way criticality analysis is performed, and iii) take advantage of the reasoning capabilities to automatically evaluate asset criticality and associate a suitable maintenance strategy. The developed ontology, called MOCA, is tested in a food company featuring a global footprint. The application shows that MOCA can accomplish the prefixed goals; specifically, high priority assets towards which direct PHM programs are identified. In the long run, ontologies could serve as a unique knowledge base that integrate multiple data and information across facilities in a consistent way. As such, they will enable advanced analytics to take place, allowing to move towards cognitive Cyber Physical Systems that enhance business performance for companies spread worldwide.

Habitual Verbs Expressing Pure Causativity in the Bulgarian Language: A Syntactic-Lexicographic ApproachThis article presents the semantics and syntax of habitual verbs expressing pure causativity in Bulgarian. The linguistic data is modelled according to the predicate-argument theory with a particular focus on syntactic condensation processes. The lexical units under investigation are presented in the form of a semantic-syntactic dictionary with examples of different types of formalisations of the two opened argument positions (“cause” and “effect”). The latter of the two positions is less compatible with non-abstract nouns as the only formal exponent of the proposition. The following units were selected for the study: Bul. води, довежда, докарва, идва от (причината), предизвиква, причинява, произлиза, произтича. Habitualne czasowniki wyrażające czystą kauzację w języku bułgarskim: w ujęciu syntaktyczno-leksykograficznymW artykule omówiono semantykę i składnię habitualnych czasowników wyrażających czystą kauzację w języku bułgarskim. Dane językowe zostały wymodelowane w oparciu o teorię predykatowo-argumentową ze szczególnym naciskiem położonym na procesy kondensacji syntaktycznej. Zbadane jednostki zostały zaprezentowane w formie semantyczno-syntaktycznego słownika z przykładami różnych typów formalizacji obu otwartych pozycji argumentowych („przyczyny” i „skutku”). Druga z omawianych pozycji jest mniej kompatybilna z rzeczownikami nieabstrakcyjnymi w funkcji jedynego wykładnika propozycji. Do badania wybrano następujące jednostki: bg. води, довежда, докарва, идва от (причината), предизвиква, причинява, произлиза, произтича.

AbstractOpen texture is a kind of semantic indeterminacy first systematically studied by Waismann. In this paper, extant definitions of open texture will be compared and contrasted, with a view towards the consequences of open-textured concepts in mathematics. It has been suggested that these would threaten the traditional virtues of proof, primarily the certainty bestowed by proof-possession, and this suggestion will be critically investigated using recent work on informal proof. It will be argued that informal proofs have virtues that mitigate the danger posed by open texture. Moreover, it will be argued that while rigor in the guise of formalisation and axiomatisation might banish open texture from mathematical theories through implicit definition, it can do so only at the cost of restricting the tamed concepts in certain ways.

This work applies knowledge engineering’s techniques to medieval illuminations. Inside it, an illumination is considered as a knowledge graph which was used by some elites in the Middle Ages to represent themselves as a social group and exhibit the events in their lives, and their cultural values. That graph is based on combinations of symbolic elements linked each to others with semantic relations. Those combinations were used to encode visual metaphors and influential messages whose interpretations are sometimes tricky for not experts. Our work aims to describe the meaning of those elements through logical modelling using ontologies. To achieve that, we construct logical reasoning rules and simulate them using artificial intelligence mechanisms. The goal is to facilitate the interpretation of illuminations and provide, in a future evolution of current social media, logical formalisation of new encoding and information transmission services.

Knowledge visualization (KV) and knowledge representation (KR) are distinguished, though both are knowledge management processes. Knowledge visualization is subject to humans, whereas knowledge representation – to computers. In computing, knowledge representation leverages reasoning of software agents. Thus, KR is a branch of artificial intelligence. The subject matter of KR is representation methods. They are classified into (1) knowledge level and symbol level representations; (2) procedural and declarative representations; (3) logic-based, rule-based, frame- or object-based representations (supporting inference by inheritance); and (4) semantic networks. In legal informatics, methods of legal knowledge representation (LKR) are dealt with. An essential feature of LKR is the representation of deep knowledge, which is mainly tacit. It is easily understood by professional jurists and hardly by amateurs from outside law. This knowledge comprises the teleology of law and a whole implicit framework of legal system. The paper focuses on (1) identifying key features of KV and KR in the legal domain; and (2) distinguishing between visualization, symbolization, formalisation and mind mapping.

Biodiversity research expeditions to the globe’s most biodiverse areas have been conducted for several hundred years. Natural history museums contain a wealth of historical materials from such expeditions, but they are stored in a fragmented way. As a consequence links between the various resources, e.g., specimens, illustrations and field notes, are often lost and are not easily re-established. Natural history museums have started to use persistent identifiers for physical collection objects, such as specimens, as well as associated information resources, such as web pages and multimedia. As a result, these resources can more easily be linked, using Linked Open Data (LOD), to information sources on the web. Specimens can be linked to taxonomic backbones of data providers, e.g., the Encyclopedia Of Life (EOL), the Global Biodiversity Information Facility (GBIF), or publications with Digital Object Identifiers (DOI). For the content of biodiversity expedition archives, (e.g. field notes), no such formalisations exist. However, linking the specimens to specific handwritten notes taken in the field can increase their scientific value. Specimens are generally accompanied by a label containing the location of the site where the specimen was collected, the collector’s name and the classification. Field notes often augment the basic metadata found with specimens with important details concerning, for instance, an organism’s habitat and morphology. Therefore, inter-collection interoperability of multimodal resources is just as important as intra-collection interoperability of unimodal resources. The linking of field notes and illustrations to specimens entails a number of challenges: historical handwritten content is generally difficult to read and interpret, especially due to changing taxonomic systems, nomenclature and collection practices. It is vital that: the content is structured in a similar way as the specimens, so that links can more easily be re-established either manually or in an automated way; for consolidation, the content is enriched with outgoing links to semantic resources, such as Geonames or Virtual International Authority File (VIAF); and this process is a transparent one: how links are established, why and by whom, should be stored to encourage scholarly discussions and to promote the attribution of efforts. the content is structured in a similar way as the specimens, so that links can more easily be re-established either manually or in an automated way; for consolidation, the content is enriched with outgoing links to semantic resources, such as Geonames or Virtual International Authority File (VIAF); and this process is a transparent one: how links are established, why and by whom, should be stored to encourage scholarly discussions and to promote the attribution of efforts. In order to address some of these issues, we have built a tool, the Semantic Field Book Annotator (SFB-A), that allows for the direct annotation of digitised (scanned) pages of field books and illustrations with Linked Open Data (LOD). The tool guides the user through the annotation process, so that semantic links are automatically generated in a formalised way. These annotations and links are subsequently stored in an RDF triplestore. As the use of the Darwin Core standard is considered best practice among collection managers for the digitisation of their specimens, our tool is equipped with an ontology based on Darwin Core terms, the NHC-Ontology, which extends the Darwin Semantic Web (DSW) ontology. The tool can annotate any image, be it an image of a specimen with a textual label, an illustration with a textual label or a handwritten species description. Interoperability of annotations between the various resources within a collection is therefore ensured. Terms in the ontology are structured using OWL web ontology language. This allows for more complex tasks such as OWL reasoning and semantic queries, and facilitates the creation of a richer knowledge base that is more amenable to research.

The purpose of the paper is to definite the features of the military view of the current stage of the Russian-Ukrainian war, as one of the part of its contemporary «multiplex» vision. The research methodology combines quantitative (content analysis, statistical calculations) and qualitative (structural semiotic-semantic analysis) methods with culturological interpretation of the outcomes. Moreover, some personal observations of the authors on social platforms in Ukraine have been used. The scientific novelty consists in the theoretical reconstruction of the visual image of «war through the eyes of the military», which is markedly different from every day and journalistic assumptions about it. Conclusions. As a result of a quantitative content-analysis of the photocontent of the official Facebook-page of the Kholodny Yar 93rd separate mechanised brigade, the most popular among the 23 infantry brigades of the Armed Forces of Ukraine, the authors came to the conclusion that it forms a special point of view – «war through the eyes of the military». Paradoxically, the war does not look like a chain of combat operations with the massive use of tanks, artillery, and other weapons, the result of which is the destruction of the maximum number of enemies. It appears as a special type of human existence. This was the result of the intersection of the «peaceful» beliefs of the Operator, the professional media people who generated this content, and the real combat environment in which the shooting took place. The specified vision performs a motivational function for the active pro-Ukrainian community, which is the main audience of this page. Recognition of the peculiarities of other visions of the Russian-Ukrainian war current phase, for example, a purely journalistic one, can become a relevant direction of further research, an important component of the scientific formalisation of the modern view of it. Key words: content-analysis, media, military vision, Russian-Ukrainian war, Ukrainian culture, Facebook.

Understanding the specifics of creativity, the features of the artistic method of not a single artist can be achieved without a meaningful analysis of their works. The purpose of this study is to analyse three works by the Czech artist A. Mucha “Madonna of the Lilies”, the Poster for “The Lottery of the Union of Southwest Moravia” and the Poster for “The Slav Epic Exhibition”, to reveal the programmatic content of each of these works, as well as their general artistic idea. The works by A. Mucha were analysed using the method proposed and justified in the field of theory and history of culture by the Russian scientist V.I. Zhukovsky. This technique determined the logic of analysis of the selected works. Such methods as observation, formalisation, analysis, synthesis, analogy, extrapolation and interpretation were applied. The result of a methodical analysis of the three selected works by A. Mucha testifies to the programmatic creativity of the artist, to a single semantic regularity in his works. The key theme uniting all three works being analysed is the theme of divine patronage of the homeland (native land, people). However, the authors draw attention to a number of aspects of visualisation of this topic in each of the works. If the work “Madonna of the Lilies” expresses the idea of patronage in its very initial moment, the moment of faith in patronage coming from above, then in the poster of the lottery divine patronage becomes doubtful. Nevertheless, the analysis of the poster for “the Lottery of the Union of Southwest Moravia” revealed a number of artistic signs indicating the possibility of a revival of faith in patronage. Based on the interpretation of these signs, such conditions for the revival of faith as the lack of fear “to look and see, to fight” were formulated. Confirmation of the idea of revival is expressed in the third analysed work of the artist, i.e. the poster for “The Slav Epic Exhibition”. Methodical analysis allowed us to characterise this work as a statement of fulfilled expectations, prosperity and dawn at the same time. The terms “death, withering, fossil”, which are defined as temporary phenomena, act as a programmatic condition expressed through the artistic signs of the work

Cute pictures of animals feature as an inoffensive and adorable background to the contemporary online experience with cute content regularly shared on social media platforms. Indeed the demand for cuteness is so strong in the current cultural milieu that some animals become recognisable animal celebrities in the process (Hepola). However, despite the existence of this professionalisation in some sections of the cute economy, amateurs produce the majority of cute content that circulates online. This is largely because one of the central contributors to this steady stream of cute animal pictures is the subforum Aww, hosted on the online community Reddit. Aww is wholly dedicated to pictures of cute things and allows users to directly submit cute content directly to the site. Aww is one of the default subforums that new Reddit users are automatically subscribed to and is immensely popular, featuring over 4.2 million dedicated subscribers as well as untold casual visits. The section is self-described as: “Things that make you go AWW! -- like puppies, and bunnies, and so on...Feel free to post pictures, videos and stories of cute things” ("The cutest things on the internet!"). Users upload cute animal photos that they have taken and wait for the Reddit community to vote on their favourite pictures. The voting mechanism helps users to acknowledge their favourite posts, with the most popular featured on the front page of Aww (for a detailed critique of this process see van der Nagel 2013). The user-generated model of the site means that instead of visitors being confronted with a formally curated selection of cute animal photos, Aww offers a constantly changing mixture of amateur, semi-pro and professional content. Aww - and Reddit more generally - stand as an emblematic example of participatory culture (Jenkins 2006), with users playing an active role in the production and curation of online content. However, given the commercial nature of many user-generated content sites, this amateur media activity is becoming increasingly subject to intellectual property claims and conflicts (see Burgess; Kennedy). Across the internet there are growing tensions between website operators and amateur producers. As Jenny Kennedy (132) notes, while these platforms promote a public rhetoric of “sharing”, these corporate narratives “downplay their economic power” and imply “that they do not control the practices contained within their sites”. Subsequently, the expectations of users regarding how content is managed and organised can differ substantially from the corporate goals of social media companies. This paper contributes to the growing body of literature interested in the politics of amateur media production (see Hunter and Lastowka; Benkler; Burgess; Kennedy) by exploring the emergence of attribution norms and informal enforcement measures in and around the Aww online community. In contrast to professional content creators, amateurs often have fewer resources on hand to protect their copyrighted work and are also challenged by a pervasive online rhetoric that suggests that popular content essentially “belongs to the Internet” (Douglas). A number of communities on Reddit have questioned the company’s handling of amateur content with users suggesting that Reddit actively seeks to de-contextualise original content and not attribute original creators. By examining how amateur creators and online communities regulate content online, I interrogate the power relations that exist between social media platforms and users and explore how the corporate rhetoric of participatory culture interacts with the legal framework of copyright law. This article also contributes to existing legal scholarship on communities of practice and norms-based intellectual property systems. This literature has explored how social norms effectively regulate the protection of, among other things, recipes (Fauchart and Von Hippel), fashion design (Raustiala and Sprigman) and stand-up comedy routines (Oliar and Sprigman), in situations where copyright law does not function as an effective regulatory mechanism. Often these norms are in line with copyright law protections, but in other cases they diverge from these legal principles. In this paper I suggest that particular sections of Reddit function in a similar way, with their own set of self-governing norms, and that these norms largely align with the philosophical aims of copyright law. The paper begins by outlining a series of recent debates that have occurred between amateur media creators and Reddit, before exploring how norms are regulated on Reddit subforums Aww and Karma Court. I then offer some brief conclusions on the value of paying attention to how social norms structure forms of “sharing” (see Kennedy) and provide a useful way for amateur media producers to protect their content without going through formal legal processes. Introducing Reddit and the Confused Politics of Amateur Content Reddit is a social news site, a vibrant community and one of the most popular websites online. It stands as the most visible iteration of a long-standing tradition of user-generated and managed news, one that goes back to websites like Slashdot, which operated in the mid to late-90s. Founded in 2005 Reddit was launched after only one funding round of venture capital, receiving $100k in seed funding from Y Combinatory (Miller). Despite some early rivalry between Reddit and competitor site Digg, Reddit had enough potential to be purchased by Condé Nast for an estimated $20 million (Carr). Reddit’s audience numbers have grown exponentially in the last few years, with the site currently receiving over 5 billion page views and 114 million unique visitors per month (“About Reddit”). It has also changed focus significantly in the last few years with the site now “as much about posting interesting or funny pictures as it is about news” (Sepponen). Reddit hosts a number of individual subforums (called subreddits), which focus on a particular topic and function essentially like online bulletin boards. The front-page of Reddit showcases the most popular content from across the whole website, and user-generated content features heavily here. Amateur media cannot spread without the structural support of social media platforms, but this support is qualified in particular ways. Reddit stands as a paradigmatic case. Users on Reddit are “incentivized to submit direct links to images, because viewers can get to them more easily” (Douglas) and the website encourages amateur creators to use a preferred content server – Imgur – to host images. The Imgur service provides a direct public link to an image – even bypassing the Reddit discussion page – and with its free hosting and limited ads it has become a popular service and is used by most Reddit users (Slater-Robins). For the majority of Reddit users this is an unproblematic partnership. Imgur is free, effective and fast. However, a vocal minority of Reddit users and amateur creators claim that the partnership between Reddit and Imgur has created the equivalent of an online ghetto (Douglas).As Nick Douglas explains, when using services like Imgur there is no requirement to either provide an external link to a creators website or to attribute the creator, limiting the ability for an amateur creator to gain exposure. It also bypasses existing revenue streams that may have been set up by creators, including ad-supported websites or online stores offering merchandise. As a result creators have little opportunity to benefit either economically or reputationally from this system. This occurs to such an extent that “there are actually warnings against submitting your own [original] work” to particular subforums on Reddit (Douglas). For example, some forum moderators require submissions to either “link directly to a specific image file or to a website with minimal ads” (“Reddit Pics”). It is in this context, that the posting of original content without attribution is not actively policed. There are a number of complaints circulating within the Reddit community about these practices (see “Ok, look people. I know you heart Imgur, but webcomics? Just link to the freaking site”; “The problem with reddit”). Many creators have directly protested against this aspect of Reddit’s structural organisation. Blogger Benjamin Grelle (a.k.a The Frogman) and writer Chris Menning are two notable examples. Grelle’s protest was witty and dramatic. He wrote a blog post featuring a picture of an email he sent to Imgur offering the company a choice: send him a huge novelty check for $10,000 or alternatively, add a proper attribution system that allows artists, photographers and content creators to properly credit their work. Grelle estimates that his work generated around $20,000 in ad revenue for Imgur; however the structure of Reddit and Imgur meant he earned little income from the “viral” success of his content. Grelle claimed he was happy for his work to be shared, but attribution meant that it was more likely a fan would follow the link to his website and provide him with some financial recompense for his work. Unsurprisingly, Grelle didn’t receive a paycheck and so in response has developed a unique way to gain exposure. He has started to insert himself into his work, “[s]o when you see a stolen Frogman piece, you still see Ben Grelle’s face” (Douglas). Chris Menning posted a blog about being banned from Reddit, hoping to bring to light some of the inequalities that persist around Reddit’s current structure. He began by noting that he had received a significant amount of traffic from them in the past. He had responded in kind by looking to create original content for particular subforums, knowing what a particular community would enjoy. However, his habit of providing the link to his own website along with the content he posted saw him get labelled as a spammer and banned by administrators. Menning chose not to fight the ban:It seems that the only way I could avoid [getting banned] is if I were to relinquish any rights to my original content and post it exclusively to Imgur. In effect, reddit punishes the creation of original content, and rewards content theft (Menning). Instead he decided to quit Reddit, claiming that Reddit’s approach would carry long-term consequences as the platform provided little incentive for creators to produce wholly original content. It is worth noting that neither Menning nor Grelle turned to legal avenues in order to gain financial restitution. Considering the nature of the practices they were complaining about, compensation in the form of an injunction or damages would have certainly been possible. In Benjamin’s case, a user had combined a number of his copyrighted works into one image and posted the image to Imgur without attribution --this infringed Grelle’s copyright in his work as well as his moral right to be attributed as the creator of the work. However, the public comments of both creators suggest that despite the possibility of legal success, their issue was not so much to do with their individual cases but rather the broader structural issues at play within Reddit. While they might gain individually from a successful legal challenge, over the long term Reddit would continue to be a fraught place for amateur and semi-professional content creators. Certain parts of the Reddit community appear to be sympathetic to these issues, and the complaints of dissenting users like Menning and Grelle have received active support from some users and moderators on the site. This has led to changes in the way content is being posted and managed on Aww, and has also driven the emergence of a satirical user-run court entitled Karma Court. In these spaces moderators and members establish community norms, regularly police the correct attribution of works and challenge the de-contextualisation of content overtly encouraged by Reddit, Imgur and other subforums. In the following section I will examine both Aww and Karma Court in order to explore how these norms are established and negotiated by both moderators and users alike. reddit.com/r/aww: The Online Hub of Cute Animal Pictures As we have seen, the design of Reddit and Imgur creates a number of problems for amateur creators who wish to protect their intellectual property. To address these shortcomings, the Aww community has created its own informal regulatory systems. Volunteer moderators play a crucial role: they establish informal codes of conduct for the Aww community and enforce various rules about how the site should be used. One of these rules relates to attribution. Users are asked to to “post original content whenever possible or attribute original content creators” ("The cutest things on the internet!"). Due to the volunteer nature of the work and the size of the Aww sub-reddit, moderator enforcement is haphazard. Consequently, responsibility falls on the wider user community to self-police. Despite its informal nature, this process manages to facilitate a fairly consistent standard of attribution. In this way it functions as an informal method of intellectual property protection. It is worth noting however that this commitment to original content is not solely due to the moral character of Aww users. A significant motivation is the distribution of karma points amongst Reddit users. Karma, which represents your good standing within the Reddit community, can be earned through user likes and votes – these push the most popular content to the front page of each subforum. Thus karma stands as a numerical representation of a user’s value to Reddit. This ostensibly democratic system has the paradoxical effect of fuelling intellectual property violations on the site. Users often repost other users’ jpegs, animated gifs, and other content, in order to reap the social and cultural capital that comes with posting a popular picture. In some cases they claim authorship of the content; in other cases they simply re-post content that they feel “belongs to the internet” (Douglas). Some content is so popular or pervasive online (this content that is often described as “viral”) that users feel there is little reason or need to attribute content. This helps to explain the persistence of ownership and attribution conflicts on Reddit. In the eyes of some users and moderators the management of these rights and the correct distribution of karma are seen to be vital to the long-term functioning of site. The karma system offers a numerical representation of each contributor’s value. Re-posting already successful content and claiming it as your own challenges the proper functioning of the karma system and potentially ‘inhibits the innovative potential of contributions (Richterich). On Aww the re-posting of original content is viewed as a taboo act that breaches these norms. The poster is seen to have engaged in deceptive conduct in order to gain karma for their user profile. In addition there is a strong ethic that runs through these comment threads that the original creator deserves attribution. There is a presumption that this attribution is vital in order to increasing the possible marketability of the posted content and to recognise and courage creators within the community. This sort of community-driven regulation contrasts with the aforementioned site design of Reddit and Imgur, which frustrates effective authorship attribution practices. Aww users, in contrast, have shown a willingness to defend what they see as the intellectual property rights of content creators.A series of recent examples outline how this process works in practice. User “moonlikeme123” posted a picture of a cat with its hands on the steering wheel of a car. The picture was entitled “we don’t need to ask for directions, Helen”. During the same day, three separate users had identified the picture as a repost, with one noting that the same picture was already on the front page of Aww. “moonlikeme123” received no karma points for the picture. In a second example, the user “nibblur” posted a photo of a kitten “hunting” a toy mouse. Within a day, one enterprising user had identified the original photographer – “torode”, an amateur photographer – and linked to his Reddit profile (see fig. 2) ("ferocious cat hunting its prey: aww."). One further example: on 15 July 2013 “Cuzacelmare” posted a picture of two dogs comforting each other – an image which had originally been posted by “lauface”. Again, users were quick to point out the lack of attribution and the attempt to claim someone else’s content as their own (“Comforting her sister during a storm: aww). It is worth noting that some Reddit users consider attributing content to be entirely without benefit. Some deride karma as “meaningless” and suggest that as a significant amount of content online is regularly reposted elsewhere, there is little harm done in re-posting what is essentially amateur content destined to be lost in the bowels of the internet. For example, the comments that follow Cuzacelmare’s reflect an ambivalence about reposting, suggesting that users weigh up the benefits of exposure gained by the re-posting against the lack of attribution granted and the increasingly decontextualized nature of the photo itself:Why does everyone get so bitchy about reposts. Not everyone is on ALL the time or has been on Rreddit since it was created. I mean if you've seen it already ignore it. It's just picture you aren't forced to click the link. [sic] (“Comforting her sister during a storm: aww”)We're arguing semantics, but any content that gets attention can benefit the creator, whether it's reddit or Youtube (“Comforting her sister during a storm: aww”) Such discussions are common on comment threads following re-posts by other users. They underline the conflicted status of this ephemeral media and the underlying frictions that are part of these processes. These discussions underline the fact that on Reddit the “sharing” (Kennedy) and “spreading” (Jenkins et al.) of content is not seen as an unquestioned positive but rather as a contestable structural feature that needs to be constantly negotiated and discussed. These informal methods of identification, post-hoc attribution and criticism in comment threads have been the long-standing method used to redress questions of attribution and ownership of content on Reddit. However in recent times, Reddit users have turned to satirical methods of formal adjudication for particularly egregious cases. A sub-reddit, Karma Court, now functions as an informal tribunal in which punishment is meted out for “the abuse of karma and general contemptible actions heretofore identified as wrongdoing” (“Constitution and F.A.Q of the Karma Court”). Due to its double function as both an adjudicator and satire of users overly-invested in online debates, there is no limit to the possible “crimes” a user may be charged with. The following charges are only presented as guidelines and speak to common negative experiences on online: (1). Douchebaggery - When one is being a douche.(2). Defamation - Tarnishing another redditor's [user’s] username.(3). Public Indecency - When a user flexes his or her 'e-peen' with the intent to shame other users.(4). OhShit.exe - Intentional reposting that results in reddit Gold.(5). GrandTheft.jpg - Reposting while claiming credit for the post.(6). Obstruction of Justice - Impeding or interfering with an investigation, such as submitting false screenshots, deleting evidence, or providing false evidence to the court.(7). Other - Literally anything else you want. We like creative names for charges.(“Constitution and F.A.Q of the Karma Court”) In Karma Court, legal representation can be sourced from a list of attorneys and judges, populated by users who volunteer to help adjudicate the case. They are required to have been a Reddit member for over six months. The only punishment is a public shaming. Interestingly Karma Court has developed a fair reposting clause that attempts to manage the complex debates around reposting and attribution. Under the non-binding satirical clause, users are able to repost content if it has not featured on the front page of a sub-reddit for seven or more days, if the re-poster acknowledges in the title or description that they are re-posting or if the original poster has less than 30,000 link karma (which means that the original poster has not substantially contributed to the Reddit community). If a re-poster does not adhere by these rules and claims a re-post as their own original content (or “OC”), they can be charged with “grandtheft.jpg” and brought to trial by another Reddit user. As one of the most popular subforums, a number of cases have emerged from Aww. The aforementioned re-poster “Cuzacelmare” (“I am bringing /U/ Cuzacelmare to trial …”) was “charged” through this process and served with a summons after denying “cute and innocent animals of that subreddit of their much deserved karma”. Similar cases to do with re-posting without attribution on Aww involve “FreshCorio” (“Reddit vs. U/FreshCorio …”) and “ninjacollin” (“People of Reddit vs. /U/ ninjacollin”) who were also brought to karma court. In each case prosecutors were adamant that false authorship claims needed to be punished. With these mock trials run by volunteers it takes time for arguments to be heard and judgment to occur; however “ninjacollin” expedited the legal process by offering a full confession. As a new user, “ninjacollin” was reprimanded severely for his actions and the users on Karma Court underlined the consequences of not identifying original content creators when re-posting content. Ownership and Attribution: Amateur Media, Distribution and Law The practices outlined above offer a number of alternate ways to think about amateur media and how it is distributed. An increasingly complex picture of content attribution and circulation emerges once we take into account the structural operation of Reddit, the intellectual property norms of users, and the various formal and informal systems of regulation that are appearing on the site. Such practices require users to negotiate complex questions of ownership between each other and in relation to corporate bodies. These negotiations often lead to informal agreements around a set of norms to regulate the spread of content within a particular community, suggesting that the lack of a formal legal process in these debates does not mean that there is an absence of regulation. As noted throughout this paper, the spread of online content often involves progressive de-contextualisation. Website design features often support this process in the hopes of encouraging content to spread in a fashion amenable to their corporate goals. Considering this tendency for content to be decontextualized online, the presence of attribution norms on subforums like Aww is significant. Instead of remixing, spreading and re-purposing content indiscriminately, users retain a concept of ownership and attribution that tracks closely to the basic principles of copyright law. Rather than users radically redefining concepts of attribution and ownership, as prefigured in some of the more utopian accounts of participatory media, the dominant norms of the Reddit community extend a discourse of copyright and ownership. As well as providing a greater level of detail to contemporary debates around amateur media and its viral or spreadable nature (Burgess; Jenkins; Jenkins et al), this analysis offers some lessons for copyright law. The emergence of norms in particular Reddit subforums which govern the use of copyrighted content and the use of a mock court structure suggests that online communities have the capacity to engage in forms of redress for amateur creators. These organic forms of copyright management operate adjacent to formal legal structures of copyright law. However, they are more accessible and practical for amateur creators, who do not always have the money to hire lawyers, especially when the market value of their content might be negligible. The informal regulatory systems outlined above may not operate perfectly but they reveal communities who are willing to engage foundational conversations around the importance of attribution and ownership. Following the existing literature (Fauchart and Von Hippel; Raustiala and Sprigman; Schultz; Oliar and Sprigman), I suggest that these online social norms provide a useful form of alternative protection for amateur creators. Acknowledgements Thanks to Ramon Lobato and Emily van der Nagel for comments and productive discussions around these issues. I am also grateful to the two anonymous peer reviewers for their assistance in developing this argument. References “About Reddit.” Reddit, 2014. 29 Apr. 2014 ‹http://www.reddit.com/about/›. Benkler, Yochai. The Wealth of Networks: How Social Production Transforms Markets and Freedom. New Haven: Yale University Press, 2006. Burgess, Jean. “YouTube and the Formalisation of Amateur Media.” Amateur Media: Social, Cultural and Legal Perspectives. In Dan Hunter, Ramon Lobato, Megan Richardson, and Julian Thomas, eds. Oxford: Routledge, 2012. Carr, Nicholas. “Left Alone by Its Owner, Reddit Soars.” The New York Times: Business, 2 Sep. 2012. “Comforting Her Sister during a Storm: aww.” reddit: the front page of the internet, 15 July 2013. “Constitution and F.A.Q of the Karma Court.” reddit: the front page of the internet, 2014. Douglas, Nick. “Everything on the Internet Gets Stolen: Here’s How You Should Feel about That.” Slacktory, 8 Sep. 2009. Fauchart, Emmanual, and Eric von Hippel. “Norms-Based Intellectual Property Systems: The Case of French Chefs.” Organization Science 19.2 (2008): 187 - 201 "Ferocious Cat Hunting Its Prey: aww." reddit: the front page of the internet, 4 April 2013. 29 Apr. 2014 ‹http://www.rreddit.com/r/aww/comments/1bobcp/ferocious_cat_hunting_its_prey/›. Hepola, Sarah. “The Internet is Made of Kittens.” Salon.com, 11 Feb. 2009. 29 Apr. 2014 ‹http://www.salon.com/2009/02/10/cat_internet/›. Hunter, Dan, and Greg Lastowka. “Amateur-to-Amateur.” William & Mary Law Review 46 (2004): 951 - 1030. “I Am Bringing /U/ Cuzacelmare to Trial on the Basis of Being One of the Biggest _______ I’ve Ever Seen, by Reposting Cute Animal Pictures to /R/Awww. Feels.Jpg.” reddit: the front page of the internet, 21 March 2013. Jenkins, Henry. Convergence Culture: Where Old and New Media Collide. New York: New York University Press, 2006. Jenkins, Henry, Sam Ford, and Joshua Green. Spreadable Media: Creating Value and Meaning in a Networked Culture. New York: New York University Press, 2013. Menning, Chris. "So I Got Banned from Reddit" Modern Primate, 23 Aug. 2012. Miller, Keery. “How Y Combinator Helped Shape Reddit.” Bloomberg Businessweek, 26 Sep. 2007. 29 Apr. 2014 ‹http://www.businessweek.com/stories/2007-09-26/how-y-combinator-helped-shape-redditbusinessweek-business-news-stock-market-and-financial-advice›. “Ok, Look People. I Know You Heart Imgur, But Webcomics? Just Link to the Freaking Site.” reddit: the front page of the internet, 22 Aug. 2011. Oliar, Dotan, and Christopher Sprigman. “There’s No Free Laugh (Anymore): The Emergence of Intellectual Property Norms and the Transformation of Stand-Up Comedy.” Virginia Law Review 94.8 (2009): 1787 – 1867. “People of reddit vs. /U/Ninjacollin for Grandtheft.jpg.” reddit: the front page of the internet, 30 Jan. 2013. Raustiala, Kal, and Christopher Sprigman. “The Piracy Paradox: Innovation and Intellectual Property in Fashion Design”. Virginia Law Review 92.8 (2006): 1687-1777. “Reddit v. U/FreshCorio. User Uploads Popular Repost Picture of R/AWW and Claims It Is His Sister’s Cat. Falsely Claims It Is His Cakeday for Good Measure.” reddit: the front page of the internet, 12 Apr. 2013. 29 Apr. 2014 ‹http://www.reddit.com/r/KarmaCourt/comments/1c7vxz/reddit_vs_ufreshcorio_user_uploads_popular_repost/›. “Reddit Pics.” reddit: the front page of the internet, 2014. 29 Apr. 2014 ‹http://www.reddit.com/r/pics/›. Richterich, Annika. “’Karma, Precious Karma!’ Karmawhoring on Reddit and the Front Page’s Econometrisation.” Journal of Peer Production 4 (2014). 29 Apr. 2014 ‹http://peerproduction.net/issues/issue-4-value-and-currency/peer-reviewed-articles/karma-precious-karma/›. Schultz, Mark. “Fear and Norms and Rock & Roll: What Jambands Can Teach Us about Persuading People to Obey Copyright Law.” Berkley Technology Law Journal 21.2 (2006): 651 – 728. Sepponen, Bemmu. “Why Redditors Gave Imgur a Chance.” Social Media Today, 20 July 2011. Slater-Robins, Max. “From Rags to Riches: The Story of Imgur.” Neowin, 21 Apr. 2013. "The Cutest Things on the Internet!" reddit: the front page of the internet, n.d. “The Problem with reddit.” reddit: the front page of the internet, 23 Aug. 2012. 29 Apr. 2014 ‹http://www.rreddit.com/r/technology/comments/ypbe2/the_problem_with_rreddit/›. Van der Nagel, Emily. “Faceless Bodies: Negotiating Technological and Cultural Codes on reddit gonewild.” Scan: Journal of Media Arts Culture 10.2 (2013). "We Don’t Need to Ask for Directions, Helen: aww." reddit: the front page of the internet, 30 June 2013. 29 Apr. 2014 ‹http://www.rreddit.com/r/aww/comments/1heut6/we_dont_need_to_ask_for_directions_helen/›.