Gillian Russell

Deductive Logic is an introductory textbook in formal logic. The book is divided into four parts covering (i) truth-functional logic, (ii) monadic quantifi- cation, (iii) polyadic quantification and (iv) names and identity, and there are exercises for all these topics at the end of the book. In the truth-functional logic part, the reader learns to produce paraphrases of English statements and arguments in logical notation (this subsection is called “analysis”), then about the semantic properties of such paraphrased statements and arguments, such as satisfiability, implication and equivalence (“logical assessment”) and finally (“reflection”) there is an axiomatic proof method and some important extras such as disjunctive normal form and expressive adequacy. Parts two and three mirror this analysis/assessment/reflection structure for monadic and polyadic quantification, though this time the proof system is a natural deduction one, and part three contains a completeness proof for that system. The fourth part of the book introduces names, the identity predicate and descriptions and examines the additional expressive power which these provide.

This paper investigates, formulates and proves an indexical barrier theorem, according to which sets of non-indexical sentences do not entail (except under specified special circumstances) indexical sentences. It surveys the usual difficulties for this kind of project, as well some that are specific to the case of indexicals, and adapts the strategy of Restall and Russell's "Barriers to Implication" to overcome these. At the end of the paper a reverse barrier theorem is also proved, according to which an indexical sentence will not, except under specified circumstances, entail a non-indexical one

Machine generated contents note: -- Series Editors' PrefaceAcknowledgementsNotes on ContributorsHow Things Are Elsewhere; W. Schwarz Information Change and First-Order Dynamic Logic; B.Kooi Interpreting and Applying Proof Theories for Modal Logic; F.Poggiolesi & G.Restall The Logic(s) of Modal Knowledge; D.Cohnitz On Probabilistically Closed Languages; H.Leitgeb Dogmatism, Probability and Logical Uncertainty; B.Weatherson & D.Jehle Skepticism about Reasoning; S.Roush, K.Allen & I.HerbertLessons in Philosophy of Logic from Medieval Obligations; C.D.Novaes How to Rule Out Things with Words: Strong Paraconsistency and the Algebra of Exclusion; F.Berto Lessons from the Logic of Demonstratives; G.RussellThe Multitude View on Logic; M.Eklund Index.

Recent work on analyticity distinguishes two kinds, metaphysical and epistemic. This paper argues that the distinction allows for a new view in the philosophy of logic according to which the claims of logic are metaphysically analytic and have distinctive modal profiles, even though their epistemology is holist and in many ways rather Quinean. It is argued that such a view combines some of the more attractive aspects of the Carnapian and Quinean approaches to logic, whilst avoiding some famous problems

In his recent Philosophers’ Imprint paper “The (mostly harmless) inconsistency of knowledge attributions” [Weiner, 2009], Matt Weiner argues that the semantics of the expression “knows that”, as it is used in attributions of knowledge like “Hannah knows that the bank will be open,” are inconsistent, but that this inconsistency is “mostly harmless.” He presents his view as an alternative to the invariantist, contextualist and relativist approaches currently prevalent in the literature, (e.g. [Stanley, 2005], [DeRose, 1995], [Hawthorne, 2006], [MacFarlane, 2005]) and argues that it avoids important disadvantages of each. Yet in calling the supposed inconsistency of knowledge attributions “mostly harmless”, Weiner implies that his view does not have new disadvantages of its own. My purpose in the present paper is to argue that the inconsistency and harmlessness theses cannot be jointly maintained: if we accept that the semantics of ‘know’—or indeed any word—are inconsistent, then we face a dilemma: one horn is dialetheism, the view that there there are true contradictions, the other is the view that that semantic competence in English requires belief in, or similar commitment to, falsehoods. I will argue that neither of these options is well described as “mostly harmless.” The paper is structured as follows: in the first part I present Weiner’s view and his arguments for it. Then in section 2 I compare the question of whether the semantics of ‘knows that’ are inconsistent to the much older controversy over whether the semantics of the expression ‘is true’ are inconsistent. In section 3 I will present Hans Herzberger’s arguments from the 1960s for thinking that no expression in a natural language can have inconsistent semantics. Finally, in section 4 I argue that although Herzberger’s argument seems anachronistic today, both contemporary ways of avoiding his conclusion have significant disadvantages.

An important part of learning to fight is learning to overcome psychological barriers against harming others. Though there are some interesting exceptions, most human beings experience signicant internal resistance to doing harm to other people. (Marshall 1947, Grossman 1995, Morton 2004, Jensen 2012) Whatever its moral properties, this reluctance to harm can compromise the ability to fighteffectively. Hence one might think that combat training should help trainees overcome such barriers. However, on one compelling theory of evil, what makes an action evil, as opposed to merely wrong, is that it is made possible by the agent's use of learned or innate strategies to overcome the natural barriers to harming others. (Morton 2004: 34{68) If this is right, it poses a prima facie moral challenge to these aspects of fight-training. The challenge is a special case of a more general one, namely, how it could be morally permissible to make people better at harming others? That is a question that martial artists rarely take seriously. Indeed, it is commonly thought that becoming a martial artist, and teaching the martial arts, are morally supererogatory. This paper takes the special challenge seriously, and looks at what can be said in response.