"Quantum Logic and Quantum Reconstruction" Based on a talk given at the Quantum Theory: From Problems to Advances conference in Växjö Sweden. Contains a review of the theorems that connect orthomodular lattices with Hilbert space and a discussion of some of the successes and limitations of quantum logic. I also briefly suggest some connections between quantum logic and other research programs.

"Quantum Interactions with Closed Timelike Curves and Superluminal Signaling" (Jeffrey Bub lead author) This paper examines two models for closed timelike curves: Deutsch's model (DCTCs) which invokes a fixed point condition in an effort to ensure consistency, and timelike curves modeled on post-selected teleportation (PCTCs), in which consistency is supposed to be assured because anything that would happen with CTCs happens with some nonzero probability in a conventional teleportation circuit. We consider whether CTCs could be used for superluminal signaling and we offer a consistency condition that suggests the answer is yes. However, if this is correct, then neither DCTCs nor PCTCs have a systematic way to avoid the Grandfather paradox and related difficulties.

"Could Logic be Empirical" This paper revisits the issues of my 2006 "Kriske, Tupman and Quantum Logic," looking again at Kripke's critique of Putnam's "Is Logic Empirical?" It develops the idea that empirical considerations could be relevant not to what the most general logical principles are, but rather to which particular logical structures fit the world. Unike Putnam's approach, the case offered here doesn't argue that we can dissolve paradoxes by abandoning the distributive law. Rather, it stays close to orthodox assumptions about quantum mechanics. The aim is not to make a case for revising our views about logic, but to argue that there is middle ground between Putnam's view and Kripke's.

"Correlations, Contexts and Quantum Logic," (with Jeffrey Bub) [For special issue of Journal of Philosophical Logic on computation and quantum logics.] As is well-known, quantum mechanics violates Bell's Inequality, but not maximally. This has led to a good deal of research on the question "Why the quantum?" This paper offers one way of articulating the issues, looks at the relevance of the notion of contexts, and considers a possible contribution that quantum logic might make to the discussion.

"Correlations and Counterfactuals: the EPR Illusion," [Forthcoming in a festschrift for William Demopoulos.] In 1935, Einstein, Podolsky and Rosen wrote what is surely the most well-known paper in the foundations of physics. It was not until the 1960s that John Bell published his famous inequality, which showed that Einstein's preferred solution to the problem couldn't work. However, even though it has been almost 40 years since Bell's paper, what I refer to as the EPR illusion has a remarkable hold on people's thinking about entangled quantum states. This paper offers a diagnosis of the illusion -- a tendency to make unwarranted counterfactual inferences -- and also tries to make vivid why the tendency is to be resisted.

"A Loose and Separate Certainty: Caves, Fuchs and Schack on Quantum Probability One" [Forthcoming in Studies in the History and Philosophy of Modern Physics; published online April 6, 2011.] Caves, Fuchs and Schack have long defended a personalist Bayesian interpretation of quantum probability, but the case of quantum probability one is problematic for them. If such probabilities are objective, then Gleason's theorem settles all other probabilities. CFS use an old result argument of mine to urge that treating quantum probability one as objective leads to a choice between admitting action at a distance and inconsistency. I argue that this isn't the choice we face.

"Contextuality and Nonlocality in 'No Signaling' Theories" (Jeffrey Bub lead author) [Foundations of Physics, 2009, pp. 690-711.] This paper uses an elegant example from Klyachko to explore the relationship between contextuality and non-locality.

"POVMs and Hidden Variables," [Physics Letters A, v. 365 n. 4, June 2007 pp. 268-272.] Paul Busch and Adan Cabello, among others, have each proved non-hidden-variable theorems in the broad style of Kochen and Specker, but by appealing to POVMs rather than projective measurements, they produce results that apply in two dimensions, contrary to what Gleason's theorem would lead one to expect. This paper doesn't quarrel with the math, but questions the interpretation of these results.

"On Local Realism and Commutativity" (with Jeffrey Bub) [Studies in the History and Philosophy of Modern Physics 38, December 2007 pp. 863-868.] James Malley and Arthur Fine argue that interest in no-go results for non-contextual hidden variable theories is interest misplaced, since any such theory would simply amount to trying to turn a non-commutative theory into a commutative one. We argue against this diagnosis, urging that the issues here are fundamental and deep.

"Local Realism and Conditional Probability," (with Jeffrey Bub), [Foundations of Physics, Feb 14, 2006 pp. 1-17. From a Festschrift for Emilio Santos.] In several papers, Emilio Santos has maintained that there is still no loophole free confirmation of Bell-type inequalites, and hence that local realism has not been refuted. James Malley and Arthur Fine have argued for an apparently contrary claim: that purely local experiments rule out "local realism." This paper develops a connection between the arguments of Malley and Fine on the one hand and an argument that Bub offered some years ago. We also argue that the apprarent disagreement between Santos and Malley-Fine over "local realism" turns on differences in how to understand that notion.

"Kriske, Tupman and Quantum Logic: The Quantum Logician's Conundrum," [In Physical Theory and its Interpretation, W. Demopoulos and I. Pitowsky (eds.), Springer Verlag, 2006.] In 1974, Saul Kripke gave a talk on quantum logic, paying particular attention to Putnam's "Is Logic Empirical," but also offering broader reflections on the relationship between logic and reasoning. This paper, whose roots are in my dissertation from many years ago, takes a critical look at Kripke's arguments and also at the "realist" quantum logical program.

"The Metaphysics of Contextualism: Cut and Paste with Hilbert Space," [PSA 1992, vol. 11 (proceedings of the 1992 Biennial Meeting of the Philosophy of Science Association) pp. 91 - 103.] Contextual hidden variable theories break relations among quantities that Hilbert space quantum mechanics appears to sanction. This paper points out that there are degrees of contextualism, as it were, and explores some of the possibilities.

"On Arthur Fine's Solution to the Measurement Problem" [Foundations of Physics Letters, v.5 no. 2 1992.] Arthur Fine asks whether quantum physics itself can give us a reason to think that quantum measurements should have results. He invokes the idea that a measurement is a partial interaction to argue that the answer is yes. (This paper clarifies and explores Fine's proposal, raising some questions about its viability. Interested readers should note that Fine has replied to my questions in A. Fine, Found. Phys. Lett. 5 125, (1992).)

"Critical Study of The Structure and Interpretation of Quantum Mechanics and Philosophical Consequences of Quantum Theory," [Synthese, vol. 86 January 1991, pp. 99-122.] A look at two books in the foundations of quantum mechanics that stil belong on researchers' shelves.

"Jarrett's Locality Condition and Causal Paradox," [PSA l988, vol. II (proceedings of the 1988 Biennial Meeting of the Philosophy of Science Association), pp. 318-325.] Explores the ways in which violations of Jarrett's locality condiiton, also known as parameter independence appears to generate paradoxical descriptions. This might be taken as a reason to conclude that parameter independence is never violated. The paper argues that this would be too quick.

Critical Study of On the Plurality of Worlds By David Lewis," [Philosophy and Phenomenological Research, December 1988, pp. 333-352.] Although at the end of the day, I'm an incredulous starer, I think Lewis's defense of his modal realism is a magnificent exercise in analytic metaphysics. This review essay explores the book's virtues and raises some issues.

"Bub on Continuous Geometry and Quantum Logic," [The British Journal for the Philosophy of Science. 1985, pp. 313 - 324.] At one point, Jeffrey Bub thuogh that von Neumann's continuous geometry approach to quantum logic might be more intepretively useful than "orthodox" quantum logic. This paper maintains that the advantages are illusory.

"Sailing into the Charybdis: van Fraassen on Bell's Theorem," [Synthese, vol. 61,December 1984.] In "The Charybdis of Realism," Bas van Fraassen argued that quantum mechanics, via Bell's theorem, presents problems for a view that he called epistemic realism. That view holds that we can only be justified in making predictions if we are in possession of a causal account of the processes at issue. I suggest that epistemic realism as van Fraassen describes it is probably a position that no one held, but I also urge that the more plausible views in its neighborhood would be too narrow if they insisted on causal models of the sort van Fraasen describes. I argue that there is a broader realist alternative that van Fraassen ignores.

"Quantum Logic, Realism and Value-Definiteness," [Philosophy of Science, December (1983), pp. 578-602.] "Western Ontario"-style quantum logic initially adopted Putnam's view that quantum logic allowed a very srong kind of realism - a kind that, appearances to the contrary notwithstanding, would allow us to say that all quantum mechanical quantities have values. This paper breaks with that view. It also presents a no-local-hidden variables theorem without probabilities, by appeal to Kochen and Specker's result and a particuar entangled state.

"On the Logic of Pairs of Quantum Systems," [Synthese 56 (1983), pp. 47-60.] Tensor products of vector spaces give rise to vectors that can't be expressed as simple products. In the terminology that has become common since this paper was written, these are the vectors that express entangled states. This paper looks at the lattice-theoretic analog of entangled (non-factorizable) vectors and shows that they arise straightforwardly from natural constraints on products of orthmodular lattices.

"Quantum Logic and the Luders Rule," [Philosophy of Science 49, (1982), pp. 422-436] Examines the standard rule for conditionalizing quantum probability measures in light of criticisms by Geoffrey Hellman.

"On Arthur Fine's Interpretation of Quantum Mechanics," [Synthese 42 (1979) pp.91-100.] This paper amounts to what now is very old news: Bell-type results defeat attempts to treat quantum measurement as simply revealing the pre-existing values, distributed in accord with the quantum predictions. It argues that Arthur Fine's attempts to get around this result by not defining joint distributions where quantum mechanics avoids them don't work.

"God and Morality." Philosophers typically think that the Euthyphro argument, or something close to it, refutes the Divine Command theory. For what we might call the simple Divine Command Theory, this is plausible at least in this sense: the Euthyphro argument makes the Divine Command Theory very hard to swallow. However, there are sopisticated variants of the DCT and, more generally, subtler ways in which God's will, if God there be, could be relevant to what's right and wrong.

"Religious Diversity." The world is full of religions with very different doctrines. This raises obvious questions for believers. This essay explores some standard philosophical responses to religious diversity and, toward the end, offers a somewhat different suggestion. The unspoken premise is that what it means to believe is not as simple as is sometimes assumed.