During development of the Xenopus embryo, the formation of the nervous system depends on an inductive interaction between mesoderm and ectoderm. The result is a neural tube that is regionally differentiated along the anterior–posterior axis from forebrain to spinal cord (Fig. 1). The discovery of genes whose transcripts can be used as molecular markers for different regions of the nervous system has permitted reassessment of the existing theories of neural tissue formation. Although the neural inducing molecules remain elusive, the mechanism (...) by which cells interact to form a regionally differentiated nervous system is becoming clearer. (shrink)

According to Jago (2014a), logical omniscience is really part of a deeper paradox. Jago develops an epistemic logic with principles of indeterminate closure to solve this paradox, but his official semantics is difficult to navigate, it is motivated in part by substantive metaphysics, and the logic is not axiomatized. In this paper, I simplify this epistemic logic by adapting the hyperintensional semantic framework of Sedlár (2021). My first goal is metaphysical neutrality. The solution to the epistemic paradox should not require (...) appeal to a metaphysics of truth-makers, situations, or impossible worlds, by contrast with Jago’s official semantics. My second goal is to elaborate on the proof theory. I show how to axiomatize a family of logics with principles of indeterminate epistemic closure. (shrink)

Logical consequence is the relation that obtains between premises and conclusion(s) in a valid argument. Orthodoxy has it that valid arguments are necessarily truth-preserving, but this platitude only raises a number of further questions, such as: how does the truth of premises guarantee the truth of a conclusion, and what constraints does validity impose on rational belief? This volume presents thirteen essays by some of the most important scholars in the field of philosophical logic. The essays offer ground-breaking new insights (...) into the nature of logical consequence; the relation between logic and inference; how the semantics and pragmatics of natural language bear on logic; the relativity of logic; and the structural properties of the consequence relation. (shrink)

Agroecology has been proposed as a key building block for food sovereignty. This article examines the meaning, practices and potentials of ‘transformative agroecology learning’ as a collective strategy for food system transformation. Our study is based on our qualitative and action research with the European Coordination of Via Campesina to develop the European Agroecology Knowledge Exchange Network. This network is linked to the global network of La Via Campesina and builds on the strong experiences and traditions of popular education in (...) Latin American peasant movements. Rather than focusing on agroecology education as a process of individual learning, we analyse how a transformative agroecology education can be strengthened as a critical repertoire of action used by social movements to advance food sovereignty. Our analysis contributes a new theory of transformative agroecology learning based on four key characteristics or qualities: horizontalism; diálogo de saberes ; combining practical and political knowledge; and building social movement networks. While these different elements of transformative agroecology learning were present across EAKEN, they were unevenly developed and, in many cases, not systematized. The framework can help to strategically and reflexively systematize and strengthen a transformative agroecology learning approach as a key building block for food sovereignty. (shrink)

Recent work in philosophical logic has taken interesting and unexpected turns. It has seen not only a proliferation of logical systems, but new applications of a wide range of different formal theories to philosophical questions. As a result, philosophers have been forced to revisit the nature and foundation of core logical concepts, chief amongst which is the concept of logical consequence. This essay sets the contributions of the volume in context and identifies how they advance important debates within the philosophy (...) of logic. (shrink)

This paper is about the underlying logical principles of scientific theories. In particular, it concerns ex contradictione quodlibet (ECQ) the principle that anything follows from a contradiction. ECQ is valid according to classical logic, but invalid according to paraconsistent logics. Some advocates of paraconsistency claim that there are ‘real’ inconsistent theories that do not erupt with completely indiscriminate, absurd commitments. They take this as evidence in favor of paraconsistency. Michael (2016) calls this the non-triviality strategy (NTS). He argues that this (...) strategy fails in its purpose. I will show that Michael's criticism significantly over-reaches. The fundamental problem is that he places more of a burden on the advocate of paraconsistency than on the advocate of classical logic. The weaknesses in Michael's argument are symptomatic of this preferential treatment of one viewpoint in the debate over another. He does, however, make important observations that allow us to clarify some of the complexities involved in giving a logical reconstruction of a theory. I will argue that there are abductive arguments deserving of further consideration for the claim that paraconsistent logic offers the best explanation of the practice of inconsistent science. In this sense, the debate is still very much open. (shrink)

According to the logical pluralism of Beall and Restall, there are several distinct relations of logical consequence. Some critics argue that logical pluralism suffers from what I call the collapse problem: that despite its intention to articulate a radically pluralistic doctrine about logic, the view unintentionally collapses into logical monism. In this paper, I propose a contextualist resolution of the collapse problem. This clarifies the mechanism responsible for a plurality of logics and handles the motivating data better than the original (...) view. It is a major improvement that should be embraced by all logical pluralists. (shrink)

In a recent series of articles, Beall has developed the view that FDE is the formal system most deserving of the honorific “Logic”. The Simple Argument for this view is a cost-benefit analysis: the view that FDE is Logic has no drawbacks and it has some benefits when compared with any of its rivals. In this paper, I argue that both premises of the Simple Argument are mistaken. I use this as an opportunity to further reflect on how such arguments (...) can be bolstered to provide more substantial and productive support for revisionary theses about Logic. (shrink)

This paper scrutinizes the debate over logical pluralism. I hope to make this debate more tractable by addressing the question of motivating data: what would count as strong evidence in favor of logical pluralism? Any research program should be able to answer this question, but when faced with this task, many logical pluralists fall back on brute intuitions. This sets logical pluralism on a weak foundation and makes it seem as if nothing pressing is at stake in the debate. The (...) present paper aims to improve this situation by looking at a promising case study and drawing general lessons about the kind of evidence that would support logical pluralism. I argue that the best motivation for logical pluralism will ultimately be rooted in certain kinds of performative data. (shrink)

This note motivates a logic for a theory that can express its own notion of logical consequence—a ‘syntactically closed’ theory of naive validity. The main issue for such a logic is Curry’s paradox, which is averted by the failure of contraction. The logic features two related, but different, implication connectives. A Hilbert system is proposed that is complete and non-trivial.

The advocate of modal logic or relevant logic has traditionally argued that her preferred system offers the best regimentation of the theory of entailment. Essential to the projects of modal and relevant logic is the importation of non-truth-functional expressive resources into the object language on which the logic is defined. The most elegant technique for giving the semantics of such languages is that of frame semantics, a variation on which features the device of partitioned frames that divide 'points of evaluation' (...) into two types: normal points and abnormal points. This essay attempts to provide satisfying philosophical interpretations of the partitioned frame semantics for some weak modal logics and relevant logics. According to the current best interpretation, partitioned frame semantics are a kind of possible worlds semantics that appeal to 'logically impossible worlds' where the laws of logic may fail to hold. This is undermined by the fact that all of the target logics fail to satisfy criteria of expressibility needed to support the thesis that laws of logic fail to hold at abnormal points. This suggests that we should not look for a monistic interpretive paradigm for partitioned frame semantics. (shrink)

I argue that, contrary to how he is often read, Spinoza did not believe that the mind and the body were numerically identical. This means that we must find some alternative reading for his claims that they are 'one and the same thing'.

While evidence for the role of gap functions, particularly during development, has been mounting, it has remained largely correlative, linking structure with presumed functions. With the recent advent of functional antibodies raised to the junctional protein, however, it has become possible to study the role of gap junctions more directly. There is now considerable evidence indicating that they play a vital role in tissue pattern formation and differentiation by allowing direct cell‐to‐cell transfer of developmental signals or morphogens.

Local sustainable food systems have captured the popular imagination as a progressive, if not radical, pillar of a sustainable food future. Yet these grassroots innovations are embedded in a dominant food regime that reflects productivist, industrial, and neoliberal policies and institutions. Understanding the relationship between these emerging grassroots efforts and the dominant food regime is of central importance in any transition to a more sustainable food system. In this study, we examine the encounters of direct farm marketers with food safety (...) regulations and other government policies and the role of this interface in shaping the potential of local food in a wider transition to sustainable agri-food systems. This mixed methods research involved interview and survey data with farmers and ranchers in both the USA and Canada and an in-depth case study in the province of Manitoba. We identified four distinct types of interactions between government and farmers: containing, coopting, contesting, and collaborating. The inconsistent enforcement of food safety regulations is found to contain progressive efforts to change food systems. While government support programs for local food were helpful in some regards, they were often considered to be inadequate or inappropriate and thus served to coopt discourse and practice by primarily supporting initiatives that conform to more mainstream approaches. Farmers and other grassroots actors contested these food safety regulations and inadequate government support programs through both individual and collective action. Finally, farmers found ways to collaborate with governments to work towards mutually defined solutions. While containing and coopting reflect technologies of governmentality that reinforce the status quo, both collaborating and contesting reflect opportunities to affect or even transform the dominant regime by engaging in alternative economic activities as part of the ‘politics of possibility’. Developing a better understanding of the nature of these interactions will help grassroots movements to create effective strategies for achieving more sustainable and just food systems. (shrink)

The semantic tradition in logic descends from Tarski's seminal work on truth and logical consequence. In the introduction to this volume, Sagi and Woods remind us that this tradition prominently uses model theory to study languages and their interpretations. Tarski's model-theoretic definition of logical consequence is the prime example of this approach, seeking as it does to reduce logical properties to a class of operations on classical, iterative (ZF) sets. Sagi and Woods explain with admirable clarity the origins, implications, and (...) philosophical questions surrounding this project. The contributions to the volume go on to address whether this approach successfully elucidates logicality and how it intersects with the foundations of mathematics and natural language semantics. (shrink)

Local sustainable food systems have captured the popular imagination as a progressive, if not radical, pillar of a sustainable food future. Yet these grassroots innovations are embedded in a dominant food regime that reflects productivist, industrial, and neoliberal policies and institutions. Understanding the relationship between these emerging grassroots efforts and the dominant food regime is of central importance in any transition to a more sustainable food system. In this study, we examine the encounters of direct farm marketers with food safety (...) regulations and other government policies and the role of this interface in shaping the potential of local food in a wider transition to sustainable agri-food systems. This mixed methods research involved interview and survey data with farmers and ranchers in both the USA and Canada and an in-depth case study in the province of Manitoba. We identified four distinct types of interactions between government and farmers: containing, coopting, contesting, and collaborating. The inconsistent enforcement of food safety regulations is found to contain progressive efforts to change food systems. While government support programs for local food were helpful in some regards, they were often considered to be inadequate or inappropriate and thus served to coopt discourse and practice by primarily supporting initiatives that conform to more mainstream approaches. Farmers and other grassroots actors contested these food safety regulations and inadequate government support programs through both individual and collective action. Finally, farmers found ways to collaborate with governments to work towards mutually defined solutions. While containing and coopting reflect technologies of governmentality that reinforce the status quo, both collaborating and contesting reflect opportunities to affect or even transform the dominant regime by engaging in alternative economic activities as part of the ‘politics of possibility’. Developing a better understanding of the nature of these interactions will help grassroots movements to create effective strategies for achieving more sustainable and just food systems. (shrink)

The patient wished to receive an experimental drug that she was instrumental in developing. After her diagnosis, she had investigated treatments that might help her condition and discovered that a specific compound could be beneficial. To further the development of this potential drug, she obtained preclinical data, founded a company, and sought investment from venture capitalists. The company was about to begin phase I testing, but the clinical trial had not yet opened. In addition, she would not have been a (...) candidate for the study, as it excluded patients with advanced disease. To be able to administer this drug to her, the patient's team of oncologists was in the process of drafting an individual patient investigational new drug application, including the protocol for the drug's delivery, to the Food and Drug Administration. The company developing the drug had preliminarily agreed to provide it. This protocol was also under review by the institutional review board of the university, and the ethics committee was consulted to determine whether she should receive the drug. (shrink)

This detailed 1990 book describes the light and dark adaptation of receptoral and post-receptoral mechanisms from a number of perspectives. The authors emphasise the importance of the study of achromatopsia, a rare congenital condition in which the visual mechanisms that mediate day vision are absent whilst those that mediate night vision remain intact.

This book is an attack on the widespread assumption that the mind has parts and that it is the interaction between these parts which accounts for the irrational behaviour displayed un self- deception and weakness of will.

The Quine/Putnam indispensability argument is regarded by many as the chief argument for the existence of platonic objects. We argue that this argument cannot establish what its proponents intend. The form of our argument is simple. Suppose indispensability to science is the only good reason for believing in the existence of platonic objects. Either the dispensability of mathematical objects to science can be demonstrated and, hence, there is no good reason for believing in the existence of platonic objects, or their (...) dispensability cannot be demonstrated and, hence, there is no good reason for believing in the existence of mathematical objects which are genuinely platonic. Therefore, indispensability, whether true or false, does not support platonism. Mathematical platonists claim that at least some of the objects which are the subject matter of pure mathematics (e.g. numbers, sets, groups) actually exist. Furthermore, they claim that these objects differ radically from the concrete objects (trees, cats, stars, molecules) which inhabit the material world. We take the standard platonistic position to include the claim that platonic objects lack spatio-temporal location and causal powers. Many (perhaps most) mathematical platonists subscribe to this view.1 But some who call themselves (or might be called) mathematical platonists.. (shrink)

Wnt proteins are involved in a large number of events during development and disease. The crucial element in the transduction of the signal elicited by Wnt is the state and activity of β-catenin. There are two pools of β-catenin, one associated with cadherins at the cell surface and a soluble one in the cytolasm, whose state and concentration are critical for Wnt signalling. In the absence of Wnt, the cytoplasmic pool is low due to targetted degradation of β-catenin. Upon Wnt (...) signalling, β-catenin is stabilized. As a consequence, it can access the nucleus where it interacts with members of the Tcf family of transcription factors to modulate the expression of defined targets. Recent reports indicate that, in addition to Tcfs, β-catenin can interact with other nuclear proteins raising the possibility that Wnt signalling has a wider modulatory effect on transcription than is mediated by its interactions with Tcfs. BioEssays 23:311–318, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

The Quine/Putnam indispensability argument is regarded by many as the chief argument for the existence of platonic objects. We argue that this argument cannot establish what its proponents intend. The form of our argument is simple. Suppose indispensability to science is the only good reason for believing in the existence of platonic objects. Either the dispensability of mathematical objects to science can be demonstrated and, hence, there is no good reason for believing in the existence of platonic objects, or their (...) dispensability cannot be demonstrated and, hence, there is no good reason for believing in the existence of mathematical objects which are genuinely platonic. Therefore, indispensability, whether true or false, does not support platonism. (shrink)

Freud seems to have been torn between a literary and a scientific model for his enterprises. On the one hand he stresses the scientific nature of his researches to an extent which makes the suspicious reader wonder whether he protests too much. On the other hand it is well known that he regarded many writers, though predominantly Shakespeare, as anticipating his findings on the unconscious. In one famous passage in the Introductory Lectures on Psycho-analysis he places his discovery of the (...) unconscious on a par with the discoveries of Darwin and Copernicus in their effect upon man's picture of himself. He is justified, of course, and if we add Marx to this triumvirate we add a figure even closer to Freud in claiming a scientific status for his work, a scientific status which is, to the uncommitted, dubious. Theodore Mischel argues that Freud increasingly construes neurotic behaviour upon the model of ordinary intentional behaviour and, though he continued to show interest in the view that the unconscious impulses which are repressed are physiological in nature, this ideal of a reduction of the psychological to the physiological became a less active ingredient in his published work as his collaboration with Fliess receded into the past. So although he may have paid lip service to some form of psycho-physical identity, believing that mental phenomena are ultimately no more or less than physical happenings in the neurones of the brain, in mature Freud this seems to have been an idly spinning wheel. Roy Schafer has recently pointed out that many of Freud's followers use the concepts of natural science , whilst simultaneously retaining traces of anthropomorphism in their metapsychology. For instance Heinz Hartmann emphasizes the concept of a ‘higher organizing function’ which resists formulation in the mechanistic metapsychology he favours. Similar difficulties obtrude in the work of Waelder and Kohut. The significance of these conflicts leads Schafer to frame basic Freudian insights in terms of the theory of action, stressing the manner in which an action may be described in differing ways and thus allowing us to present the fact that a patient's behaviour may both tell and not tell us of his deepest anxieties. Yet curiously Schafer denies that freedom plays any part in his account whereas we would have expected a concept so central to agency to have an equally central role in any recasting of psycho-analysis in terms of the theory of action. (shrink)