Proof-theoretic semantics (P-tS) is the paradigm of semantics in which meaning in logic is based on proof (as opposed to truth). A particular instance of P-tS for intuitionistic propositional logic (IPL) is its base-extension semantics (B-eS). This semantics is given by a relation called support, explaining the meaning of the logical constants, which is parameterized by systems of rules called bases that provide the semantics of atomic propositions. In this paper, we interpret bases as collections of definite formulae and use (...) the operational view of them as provided by uniform proof-search—the proof-theoretic foundation of logic programming (LP)—to establish the completeness of IPL for the B-eS. This perspective allows negation, a subtle issue in P-tS, to be understood in terms of the negation-as-failure protocol in LP. Specifically, while the denial of a proposition is traditionally understood as the assertion of its negation, in B-eS we may understand the denial of a proposition as the failure to find a proof of it. In this way, assertion and denial are both prime concepts in P-tS. (shrink)

This article explores the various senses in which the framers of the Constitution were motivated by a pragmatist philosophical framework, and how this pragmatism influenced their vision of the best interests of the American economic system. We argue that, on various grounds, the framers would have disapproved of the excessive regulation that characterizes the current business environment.

A menu of twelve moral issues that seem to be common to all organizations is described and illustrated. This menu identifies some of the most prominent moral issues requiring individuals to decide where to draw the line between moral and immoral conduct. A review ofThe Wall Street Journal during just one week provided over sixty articles illustrating how moral issues are inherent in almost every business decision. The articles included several illustrations of stealing, lying, and fraud that are immoral, although (...) in some cases not technically illegal. Other articles illustrated conflicts of interest, influence buying, hiding information, divulging personal information, taking unfair advantage, personal decadence, interpersonal abuse, organizational abuse, rule violations, being an accessory to unethical acts, and balancing ethical dilemmas. These illustrations are intended to help individuals identify moral issues and recognize the situations when they arise so they can avoid unwitting immoral behavior. (shrink)

I reply to seven commentaries on “The Virtual and the Real”. In response to Claus Beisbart, Jesper Juul, Peter Ludlow, and Neil McDonnell and Nathan Wildman, I clarify and develop my view that virtual are digital objects, with special attention to the nature of digital objects and data structures. In response to Alyssa Ney and Eric Schwitzgebel, I clarify and defend my spatial functionalism, with special attention to the connections between space and consciousness. In response to Marc Silcox, I clarify (...) and develop my view of the value of virtual worlds, with special attention to the case where we experience these worlds as virtual. (shrink)

There are many ways the world might be, for all I know. For all I know, it might be that there is life on Jupiter, and it might be that there is not. It might be that Australia will win the next Ashes series, and it might be that they will not. It might be that my great-grandfather was my great-grandmother’s second cousin, and it might be that he was not. It might be that copper is a compound, and it (...) might be that it is not. (shrink)

Introduction: making the invisible visible -- The nobility of the material -- Research at war -- The guilded age of research -- The doctor as whistle-blower -- New rules for the laboratory -- Bedside ethics -- The doctor as stranger -- Life through death -- Commissioning ethics -- No one to trust -- New rules for the bedside -- Epilogue: The price of success.

Graeme Forbes (2011) raises some problems for two-dimensional semantic theories. The problems concern nested environments: linguistic environments where sentences are nested under both modal and epistemic operators. Closely related problems involving nested environments have been raised by Scott Soames (2005) and Josh Dever (2007). Soames goes so far as to say that nested environments pose the “chief technical problem” for strong two-dimensionalism. We call the problem of handling nested environments within two-dimensional semantics “the nesting problem”. We show that the two-dimensional (...) semantics for attitude ascriptions developed in Chalmers (2011a) has no trouble accommodating certain forms of the nesting problem that involve factive verbs such as “know” or “establish”. A certain form of the nesting problem involving apriority and necessity operators does raise an interesting puzzle, but we show how a generalized version of the nesting problem arises independently of two-dimensional semantics—it arises, in fact, for anyone who accepts the contingent a priori. We, then, provide a two-dimensional treatment of the apriority operator that fits the two-dimensional treatment of attitude verbs and apply it to the generalized nesting problem. We conclude that two-dimensionalism is not seriously threatened by cases involving the nesting of epistemic and modal operators. (shrink)

Taking a social identity approach to health behaviors, this research examines whether experimentally “activating” the human identity is an effective public-health strategy to curb the spread of COVID-19. Three goals of the research include examining: whether the human identity can be situationally activated using an experimental manipulation, whether activating the human identity causally increases behavioral intentions to protect the self and others from COVID-19, and whether activating the human identity causally increases behaviors that help protect vulnerable communities from COVID-19. Across (...) two preregistered experiments, results suggest the manipulation of identification with humanity had a significant but small effect on participants’ psychological bond with all humanity, but not their concern for all humanity. However, the manipulation had no causal effect on health-related behavioral intentions or helping behaviors that reduce the spread of COVID-19. Limitations, future directions, and direct benefits of the research are discussed. (shrink)

There is a long tradition in philosophy of using a priori methods to draw conclusions about what is possible and what is necessary, and often in turn to draw conclusions about matters of substantive metaphysics. Arguments like this typically have three steps: first an epistemic claim , from there to a modal claim , and from there to a metaphysical claim.

Does consciousness collapse the quantum wave function? This idea was taken seriously by John von Neumann and Eugene Wigner but is now widely dismissed. We develop the idea by combining a mathematical theory of consciousness (integrated information theory) with an account of quantum collapse dynamics (continuous spontaneous localization). Simple versions of the theory are falsified by the quantum Zeno effect, but more complex versions remain compatible with empirical evidence. In principle, versions of the theory can be tested by experiments with (...) quantum computers. The upshot is not that consciousness-collapse interpretations are clearly correct, but that there is a research program here worth exploring. (shrink)

Philosophy &Public Affairs, Volume 51, Issue 1, Page 33-59, Winter 2023.

In Philosophy Without Intuitions, Herman Cappelen focuses on the metaphilosophical thesis he calls Centrality: contemporary analytic philosophers rely on intuitions as evidence for philosophical theories. Using linguistic and textual analysis, he argues that Centrality is false. He also suggests that because most philosophers accept Centrality, they have mistaken beliefs about their own methods.To put my own views on the table: I do not have a large theoretical stake in the status of intuitions, but unreflectively I find it fairly obvious that (...) many philosophers, including myself, appeal to intuitions. Cappelen’s arguments make a provocative challenge to this unreflective background conception. So it is interesting to work through the arguments to see what they might and might not show.In what follows I aim to articulate a minimal notion of intuition that captures something of the core everyday philosophical usage of the term, and that captures the sense .. (shrink)

Diderot is widely praised as a master of lively, dramatic and original dialogue. This book studies the developing role of dialogue in his early writings (1745 to 1754). Diderot's earlier experiments with the dialogue form, meticulously charted and analysed by D. J. Adams, opened the way to the exploration of human communication and cooperation which lies at the heart of the Encyclopédie. At first for Diderot dialogue ended in the triumph of monologue, with one speaker reducing another to silence. But (...) one of his central problems was precisely that of solipsism. Is it possible for people to communicate effectively with each other? By engaging with this problem in his early writings Diderot gradually came to realise the epistemological importance of true dialogue as an escape from the solipsistic trap; and, slowly and hesitantly, he developed the form of communicative dialogue which was to flourish in the masterpieces of his later years. (shrink)

Although A-consciousness and P-consciousness are conceptually distinct, a refined notion of A-consciousness makes it plausible that the two are empirically inseparable. I suggest that the notion of direct availability for global control can play a central role here, and draw out some consequences.

*[[This paper is largely based on material in other papers. The first three sections and the appendix are drawn with minor modifications from Chalmers 2002c . The main ideas of the last three sections are drawn from Chalmers 1996, 1999, and 2002a, although with considerable revision and elaboration. ]].

The task of this essay is to respond to the question concerning robots and responsibility—to answer for the way that we understand, debate, and decide who or what is able to answer for decisions and actions undertaken by increasingly interactive, autonomous, and sociable mechanisms. The analysis proceeds through three steps or movements. It begins by critically examining the instrumental theory of technology, which determines the way one typically deals with and responds to the question of responsibility when it involves technology. (...) It then considers three instances where recent innovations in robotics challenge this standard operating procedure by opening gaps in the usual way of assigning responsibility. The innovations considered in this section include: autonomous technology, machine learning, and social robots. The essay concludes by evaluating the three different responses—instrumentalism 2.0, machine ethics, and hybrid responsibility—that have been made in face of these difficulties in an effort to map out the opportunities and challenges of and for responsible robotics. (shrink)

(1a) If Prince Albert Victor killed those people, he is Jack the Ripper (and Jack the Ripper killed those people). (1b) If Prince Albert Victor had killed those people, Jack the Ripper wouldn't have (and Prince Albert wouldn't have been Jack the Ripper).

Language employs various coordinators to connect propositions, a subset of which are “logical” in nature and thus analogous to the truth operators of formal logic. We here focus on two linguistic connectives and their negations: conjunction _and_ and (inclusive) disjunction _or_. Linguistic connectives exhibit a truth-conditional component as part of their meaning (their semantics), but their use in context can give rise to various implicatures and presuppositions (the domain of pragmatics) as well as to inferences that go beyond semantic/pragmatic properties (...) (the result of reasoning processes). We provide a comprehensive review of the role of the logical connectives in language and argue that three sets of factors—semantic, pragmatic, and those related to reasoning—are separate and separable, though some details may differ cross-linguistically. As a way to showcase the argument, we present two experiments in language comprehension in Spanish wherein pragmatic content was minimised and reasoning processes neutered, thus potentially highlighting what might be the default meanings of the connectives under study. In Experiment 1 we show that the conjunctive reading of inclusive disjunction is available in positive contexts other than in syntactically intricate cases such as downward entailing and free choice contexts, contrary to what has been claimed in the literature. In Experiment 2 we show that negated conjunctions and disjunctions in Spanish can easily receive the same interpretation when contrasted against the same context and, moreover, that these interpretations match those available in English, despite claims from the literature that linguistic connectives and local negation interact differently in English and Romance languages. (shrink)

Is conceptual analysis required for reductive explanation? If there is no a priori entailment from microphysical truths to phenomenal truths, does reductive explanation of the phenomenal fail? We say yes . Ned Block and Robert Stalnaker say no.

Addiction Trajectories is a collection of anthropological essays that brings a refreshingly human perspective to the scientific pursuit of addiction. This book encourages the reader to step back from the details, giving voice to the experiences of the drug user as they grapple to come to terms with their condition and the efforts of the treatment community. At the same time, the book provides insight into the machinations of the treatment community struggling to understand the scope of their task and (...) to respond to the shifting intellectual landscapes of licit and illicit drugs. The addiction trajectories framework is constructed around three themes. Theme one concerns the changing categories and concepts of addiction through time and across disciplinary boundaries. Theme two represents changes in therapeutic concepts of addiction across cultures and organisations. Theme three represents the experiences of the addicted individual. Conceptualising trajectories captures the shifting natur .. (shrink)

Why is two-dimensional semantics important? One can think of it as the most recent act in a drama involving three of the central concepts of philosophy: meaning, reason, and modality. First, Kant linked reason and modality, by suggesting that what is necessary is knowable a priori, and vice versa. Second, Frege linked reason and meaning, by proposing an aspect of meaning (sense) that is constitutively tied to cognitive signi?cance. Third, Carnap linked meaning and modality, by proposing an aspect of meaning (...) (intension) that is constitutively tied to possibility and necessity. (shrink)

In the Garden of Eden, we had unmediated contact with the world. We were directly acquainted with objects in the world and with their properties. Objects were simply presented to us without causal mediation, and properties were revealed to us in their true intrinsic glory.

[This is an edited version of a keynote talk at the conference on Neural Information Processing Systems (NeurIPS) on November 28, 2022, with some minor additions and subtractions.] -/- There has recently been widespread discussion of whether large language models might be sentient or conscious. Should we take this idea seriously? I will break down the strongest reasons for and against. Given mainstream assumptions in the science of consciousness, there are significant obstacles to consciousness in current models: for example, their (...) lack of recurrent processing, a global workspace, and unified agency. At the same time, it is quite possible that these obstacles will be overcome in the next decade or so. I conclude that while it is somewhat unlikely that current large language models are conscious, we should take seriously the possibility that successors to large language models may be conscious in the not-too-distant future. (shrink)

One of the enduring concerns of moral philosophy is deciding who or what is deserving of ethical consideration. Much recent attention has been devoted to the "animal question" -- consideration of the moral status of nonhuman animals. In this book, David Gunkel takes up the "machine question": whether and to what extent intelligent and autonomous machines of our own making can be considered to have legitimate moral responsibilities and any legitimate claim to moral consideration. The machine question poses a (...) fundamental challenge to moral thinking, questioning the traditional philosophical conceptualization of technology as a tool or instrument to be used by human agents. Gunkel begins by addressing the question of machine moral agency: whether a machine might be considered a legitimate moral agent that could be held responsible for decisions and actions. He then approaches the machine question from the other side, considering whether a machine might be a moral patient due legitimate moral consideration. Finally, Gunkel considers some recent innovations in moral philosophy and critical theory that complicate the machine question, deconstructing the binary agent--patient opposition itself. Technological advances may prompt us to wonder if the science fiction of computers and robots whose actions affect their human companions could become science fact. Gunkel's argument promises to influence future considerations of ethics, ourselves, and the other entities who inhabit this world. (shrink)

This paper examines the impact of a week-long philosophy summer camp on middle and high school-age youth with specific attention paid to the development of intellectual humility in the campers. In June 2016 a university in Texas hosted its first philosophy summer camp for youth who had just completed sixth through twelfth grades. Basing our camp on the pedagogical model of the Philosophy for Children program, our aim was specifically to develop a community of inquiry among the campers, providing them (...) with a safe intellectual space to be introduced to philosophy and philosophical discussion. In 2017 we launched a formal longitudinal study to determine what impact a week-long philosophy summer camp would have on teens and tweens. Examining quantitative and qualitative data collected from 2016–2020, we found that the camp has had a significant impact on the teenagers who have attended. In particular, we found that intellectual humility increased over the duration of their camp experience and that this increase correlates with an increased affinity for philosophy and philosophical discussion. (shrink)

A wealthy eccentric places two envelopes in front of you. She tells you that both envelopes contain money, and that one contains twice as much as the other, but she does not tell you which is which. You are allowed to choose one envelope, and to keep all the money you find inside.

A content of a subject's mental state is narrow when it is determined by the subject's intrinsic properties: that is, when any possible intrinsic duplicate of the subject has a corresponding mental state with the same content. A content of a subject's mental state is..

It is fairly well-known that certain hard computational problems (that is, 'difficult' problems for a digital processor to solve) can in fact be solved much more easily with an analog machine. This raises questions about the true nature of the distinction between analog and digital computation (if such a distinction exists). I try to analyze the source of the observed difference in terms of (1) expanding parallelism and (2) more generally, infinite-state Turing machines. The issue of discreteness vs continuity will (...) also be touched upon, although it is not so important for analyzing these particular problems. (shrink)

The term ‘emergence’ often causes confusion in science and philosophy, as it is used to express at least two quite different concepts. We can label these concepts _strong_ _emergence_ and _weak emergence_. Both of these concepts are important, but it is vital to keep them separate.

Fechner's conception of psychophysics included both “outer psychophysics” the relation between stimulus intensity and the response reflecting sensation strength, and “inner psychophysics” the relation between neurelectric responses and sensation strength. In his own time outer psychophysics focussed on the form of the psychophysical law, with Fechner espousing a logarithmic law, Delboeuf a variant of the logarithmic law incorporating a resting level of neural activity, and Plateau a power law. One of the issues on which the dispute was focussed concerned the (...) appearance of contrasts if the overall illumination was increased or decreased; another issue was the question of whether a sensation of a “just noticeable difference” established for one value of a sensory dimension appeared the same for a value elsewhere on the dimension. The development of “inner psychophysics” led through the works of Delboeuf, Solomons, Jastrow, and Thurstone to modern signal detection theory. A third line of research, devoted to the question of what was meant by the “measurement” of sensation strength, stemmed from the criticism of Fechner's work by von Kries (1882) and others. Although a valid body of science could be built up without the intervening variable called “sensation strength,” such a science might be a cumbersome representation of reality. When an optical contrast is set up, and its overall illumination is increased or decreased, subjective contrasts involving medium levels of lightness vary little as illumination varies (as a power law based on sensation ratios or a logarithmic law based on sensation differences predict), but subjective contrasts involving extreme levels of lightness might be subject to the effects of other variables. (shrink)

A natural way to think about epistemic possibility is as follows. When it is epistemically possible (for a subject) that p, there is an epistemically possible scenario (for that subject) in which p. The epistemic scenarios together constitute epistemic space. It is surprisingly difficult to make the intuitive picture precise. What sort of possibilities are we dealing with here? In particular, what is a scenario? And what is the relationship between scenarios and items of knowledge and belief? This chapter tries (...) to make sense of epistemic space. It explores different ways of making sense of scenarios and of their relationship to thought and language. It discusses some issues that arise and outlines some applications to the analysis of the content of thought and the meaning of language. (shrink)

What is involved in the meaning of our expressions? Frege suggested that there is an aspect of an expression.