Cathy Legg

Wikipedia is a goldmine of information; not just for its many readers, but also for the growing community of researchers who recognize it as a resource of exceptional scale and utility. It represents a vast investment of manual effort and judgment: a huge, constantly evolving tapestry of concepts and relations that is being applied to a host of tasks. This article provides a comprehensive description of this work. It focuses on research that extracts and makes use of the concepts, relations, facts and descriptions found in Wikipedia, and organizes the work into four broad categories: applying Wikipedia to natural language processing; using it to facilitate information retrieval and information extraction; and as a resource for ontology building. The article addresses how Wikipedia is being used as is, how it is being improved and adapted, and how it is being combined with other structures to create entirely new resources. We identify the research groups and individuals involved, and how their work has developed in the last few years. We provide a comprehensive list of the open-source software they have produced.

This paper seeks an explanation for the challenges faced by Semantic Web developers in achieving their vision, compared to the staggering near-instantaneous success of the World Wide Web. To this end it contrasts two broad philosophical understandings of meaning and argues that the choice between them carries real consequences for how developers attempt to engineer the Semantic Web. The first is Rene Descartes' “private,” static account of meaning (arguably dominant for the last four-hundred years in Western thought), which understands the meanings of signs as whatever their producers intend them to mean. The second is Charles Peirce's still relatively unknown “public,” evolutionary account of meaning, according to which the meaning of signs just is the way they are interpreted and used to produce further signs. It is argued that only the latter approach can avoid the unmanageable attempts to “preprocess” interpretation of signs on the Web that have dogged the project in its many stages, and thereby do justice to the scale, rapid changeability, and exciting possibilities of online information today.

This paper takes indexicality as a case-study for critical examination of the distinction between semantics and pragmatics as currently conceived in mainstream philosophy of language. Both a ‘pre-indexical’ and ‘post-indexical’ analytic formal semantics are examined and found wanting, and instead an argument is mounted for a ‘properly pragmatist pragmatics’, according to which we do not work out what signs mean in some abstract overall sense and then work out to what use they are being put; rather, we must understand to what use signs are being put in order to work out what they mean.

Wittgenstein's discussion of rule-following is widely regarded to have identified what Kripke called "the most radical and original sceptical problem that philosophy has seen to date". But does it? This paper examines the problem in the light of Charles Peirce's distinctive "scientific hierarchy". Peirce identifies a phenomenological inquiry which is prior to both logic and metaphysics, whose role is to identify the most fundamental philosophical categories. His third category, particularly salient in this context, pertains to general predication. Rule-following scepticism, the paper suggests, results from running together two questions: "How is it that I can project rules?", and, "What is it for a given usage of a rule to be right?". In Peircean terms the former question, concerning the irreducibility of general predication (to singular reference), must be answered in phenomenology, while the latter, concerning the difference between true and false predication, is answered in logic. A failure to appreciate this distinction, it is argued, has led philosophers to focus exclusively on Wittgenstein's famous public account of rule-following rightness, thus overlooking a private, phenomenological dimension to Wittgenstein's remarks on following a rule which gives the lie to Kripke's reading of him as a sceptic

A commentary on a paper by Aaron Sloman. Sloman argues that in order to make progress in AI, consciousness, "should be replaced by more precise and varied architecture-based concepts better suited to specify what needs to be explained by scientific theories". This original vision of philosophical inquiry as mapping out 'design-spaces' for a contested concept seeks to achieve a holistic, synthetic understanding of what possibilities such spaces embody. It therefore does not reduce to either "relations of ideas" or "matters of fact" in Hume's famous dichotomy. It is also interestingly opposite to a current vogue for 'experimental philosophy'

This piece is from a book of Charles Peirce quotes and accompanying discussions. It explores the following quote from 1902: ". . . the main reason logic is unsettled is that thirteen different opinions are current as to the true aim of the science. Now this is not a logical difficulty, but an ethical difficulty; for ethics is the science of aims. Secondly, it is true that ethics has been, and always must be, a theatre of discussion for the reason that its study consists in the gradual development of a distinct recognition of a satisfactory aim. It is a science of subtleties, no doubt; but it is not logic, but the development of the ideal, which really creates and resolves the problems of ethics."

This paper offers an expressivist account of logical form, arguing that in order to fully understand it one must examine what valid arguments make us do (or: what Achilles does and the Tortoise doesn’t, in Carroll’s famed fable). It introduces Charles Peirce’s distinction between symbols, indices and icons as three different kinds of signification whereby the sign picks out its object by learned convention, by unmediated indication, and by resemblance respectively. It is then argued that logical form is represented by the third, iconic, kind of sign. It is noted that icons uniquely enjoy partial identity between sign and object, and argued that this holds the key to Carroll’s puzzle. Finally, from this examination of sign-types metaphysical morals are drawn: that the traditional foes metaphysical realism and conventionalism constitute a false dichotomy, and that reality contains intriguingly inference-binding structures.

This substantial book is a highly original and thorough work of synthetic first philosophy. Although it has some recognizable roots in the Kantian/Sellarsian tradition of the Pittsburgh school, it adds a wealth of precise discussion of examples from science and mathematics, made possible by Macbeth's dual training in arts and sciences. It presents a developmental story of human reason bootstrapping itself towards greater power and clarity through the Western tradition (which is the sole purview of the discussion). This development is divided into three distinct stages, which might be summarized very roughly as knowledge of: i) Objects, ii) Concepts applied to Objects and iii) Concepts alone.

Much discussion of meaning by philosophers over the last 300 years has been predicated on a Cartesian first-person authority (i.e. “infallibilism”) with respect to what one’s terms mean. However this has problems making sense of the way the meanings of scientific terms develop, an increase in scientific knowledge over and above scientists’ ability to quantify over new entities. Although a recent conspicuous embrace of rigid designation has broken up traditional meaning-infallibilism to some extent, this new dimension to the meaning of terms such as “water” is yet to receive a principled epistemological undergirding (beyond the deliverances of “intuition” with respect to certain somewhat unusual possible worlds). Charles Peirce’s distinctive, naturalistic philosophy of language is mined to provide a more thoroughly fallibilist, and thus more realist, approach to meaning, with the requisite epistemology. Both his pragmatism and his triadic account of representation, it is argued, produce an original approach to meaning, analysing it in processual rather than objectual terms, and opening a distinction between “meaning for us”, the meaning a term has at any given time for any given community and “meaning simpliciter”. the way use of a given term develops over time (often due to a posteriori input from the world which is unable to be anticipated in advance). This account provocatively undermines a certain distinction between “semantics” and “ontology” which is often taken for granted in discussions of realism.