The spinal cord provides an alternative model for nerve tissue grafting experiments. Anatomo-functional correlations are easier to make here than in any other region of the CNS because of a direct implication of spinal cord neurons in sensorimotor activities. Lesions can be easily performed to isolate spinal cord neurons from descending inputs. The anatomy of descending monoaminergic systems is well defined and these systems offer a favourable paradigm for lesion-graft experiments.

Grafts of embryonic neural tissue into the brains of adult patients are currently being used to treat Parkinson's disease and are under serious consideration as therapy for a variety of other degenerative and traumatic disorders. This target article evaluates the use of transplants to promote recovery from brain injury and highlights the kinds of questions and problems that must be addressed before this form of therapy is routinely applied. It has been argued that neural transplantation can promote functional recovery through (...) the replacement of damaged nerve cells, the reestablishment of specific nerve pathways lost as a result of injury, the release of specific neurotransmitters, or the production of factors that promote neuronal growth. The latter two mechanisms, which need not rely on anatomical connections to the host brain, are open to examination for nonsurgical, less intrusive therapeutic use. Certain subjective judgments used to select patients who will receive grafts and in assessment of the outcome of graft therapy make it difficult to evaluate the procedure. In addition, little long-term assessment of transplant efficacy and effect has been done in nonhuman primates. Carefully controlled human studies, with multiple testing paradigms, are also needed to establish the efficacy of transplant therapy. (shrink)

Anamniote animals, such as fish and amphibians, are able to regenerate damaged CNS nerves following injury, but regeneration in the mammalian CNS tracts, such as the optic nerve, does not occur. However, severed adult mammalian retinal axons can regenerate into peripheral nerve segments grafted into the brain and this finding has emphasized the importance of the environment in explaining regenerative failure in the adult mammalian CNS. Following lesions, regenerating axons encounter the glial cells, oligodendrocytes and astro‐cytes, and their (...) derivatives, respectively myelin and the astrocytic scar. Experiments to investigate the influence of these components on axon growth in culture have revealed cell‐surface and extracellular matrix molecules that inhibit axon extension and growth cone motility. Structural and functional characterization of these ligands and their receptors is underway, and may solve the interesting neurobiological conundrum posed by the failure of mammalian CNS regeneration. Simultaneously, this might allow new possibilities for treatment of the severe clinical disabilities resulting from injury to the brain and spinal cord. (shrink)

Stein & Glasier suggest embryonic neural tissue grafts as a potential treatment strategy for Alzheimer's and Parkinson's disease. As an alternative, we suggest that the family of nerve growth factor-related neurotrophins and their trk (tyrosine kinase) receptors underlie cholinergic basal forebrain (CBF) and dopaminergic substantia nigra neuron degeneration in these diseases, respectively. Therefore, treatment approaches for these disorders could utilize neurotrophins.

Speciesism, difference of treatment based on an appeal to species membership, is often likened to racism and sexism, and condemned on those grounds. Some philosophers, however, reject this argument by analogy and instead forward an argument for speciesism based on a postulated right of species to compete for survival. This paper attacks this strong form of speciesism by showing that the underlying concept of ‘species’ is incoherent in the context of morality, and that strong speciesism has unacceptable corollaries.

Speciesism, difference of treatment based on an appeal to species membership, is often likened to racism and sexism, and condemned on those grounds. Some philosophers, however, reject this argument by analogy and instead forward an argument for speciesism based on a postulated right of species to compete for survival. This paper attacks this strong form of speciesism by showing that the underlying concept of ‘species’ is incoherent in the context of morality, and that strong speciesism has unacceptable corollaries.

BackgroundMany procedures currently require the use of bone grafts to replace or recover bone volume that has been resorbed. However, the patient’s opinion and preferences must be taken into account before implementing any treatment. Researchers have focused primarily on assessing the effectiveness of bone grafts rather than on patients' perceptions. Thus, the aim of this study was to explore patients' opinions regarding the different types of bone grafts used in dental treatments.MethodsOne hundred patients were randomly chosen participated in the study. (...) A standardized survey of 10 questions was used to investigate their opinions regarding the different types of bone grafts used in dental treatments. Descriptive statistics were calculated for the different variables, and absolute frequencies and percentages were used as summary measures. A value of p <0.05 was selected as the threshold for statistical significance.ResultsThe highest rate of refusal was observed for allografts and xenografts. The grafts with the lowest rates of refusal were autologous grafts and alloplastics. No significant differences were found between the various types of bone grafts in the sociodemographic variables or the refusal/acceptance variable. Similarly, no significant relations were observed between a specific religious affiliation and the acceptance/refusal rates of the various types of graft.ConclusionsAllografts and xenografts elicited the highest refusal rates among the surveyed patients, and autologous bone and alloplastics were the most accepted bone grafts. Moreover, no differences were found in the sociodemographic variables or religious affiliations in terms of the acceptance/refusal rates of the different bone grafts. (shrink)

Grafting: do we ever do anything other than that? And are we ever free from vegetal influences when we engage in its operations? For the philosopher Michael Marder, our reflections on vegetal life have a fundamental importance in how we can reflect on our own conceptions of ethics, politics, and philosophy in general. Taking as his starting point the simple vegetal conception of grafting, Marder guides the reader through his concise and numerous reflections on what could be described as a (...) vegetal philosophy. Grafts are transplants either of a shoot inserted into the trunk of another tree or, surgically, of skin (among other living tissues). They are delicate operations intended to preserve, improve, and modify both the grafted materials and the body that receives them. To graft is to create unlikely encounters, hybrid mixes, and novel surfaces. Moving across disciplinary lines, Grafts combines the lessons of plant science with the history of philosophy, semiotics, literary compositions, and political theory. Co-authoring some of the texts with other philosophers, plant scientists and artists, Marder allows their insights to be grafted onto his own, and vice versa. Weighing in on contemporary debates such as the ethics of biotechnology, dietary practices or political organization, Marder inserts an unmistakable vegetal perspective into topics of discussion where it normally wouldnt be found. Transferring the living tissue of his own texts into another context, he helps them live better, more fully, than otherwise. (shrink)

A grafted frame is a new kind of frame which combines a modal frame and some relevance frames. A grafted model consists of a grafted frame and a truth-value assignment. In this paper, the grafted frame and the grafted model are constructed and used to show the completeness of S1. The implications of S1-completeness are discussed. A grafted frame does not combine two kinds of frames simply by putting relations defined in the components together. That is, the resulting grafted frame (...) is not in the form of $\langle W, R, R'\rangle$ , or more generally, in the form of $\langle W, R, R', R'',...\rangle$ , which consists of a non-empty set with several relations defined on it. Rather, it resembles the construction of fibering proposed by D. M. Gabbay and M. Finger (see [4] and [3]). On a grafted frame, some modal worlds, which belong to the initial modal frame, are attached by some relevance frames. However, these two semantics have important differences. Consider the combined semantics involving semantics of relevance logic and modal logic. A fibred model and a grafted model proposed in this paper differ in the following respects. First, a fibred model is constructed from a class of modal models and a class of relevance models. A grafted model consists of a grafted frame and a truth-value assignment, where the grafted frame is constructed from a modal frame and some relevance frames, and the assignment is a union of a modal truth-value assignment V M and some relevance truth-value assignments V R . V M (V R ) defined in this paper is not the same as the assignment contained in a modal (relevance) model. Second, in a fibred model each relevance world is associated (or fibred) with a modal model and each modal world with a relevance model. To be the grafted frame on which a grafted model is based, it is enough to have some modal worlds attached by some relevance frames. Moreover, no relevance world is associated with a modal frame in the grafted frame. Third, fibred models are intended to provide an appropriate semantics to combined logics. Grafted frames and grafted models are inspired to characterize S1, which, containing only one modality □, is not a combined logic. It is shown in this paper that S1 is sort of a meta-logic of the intersection of S0.4 and F, where S0.4, a new system proposed in this paper, is in turn a meta-logic of the relevance logic. (shrink)

A grafted frame is a new kind of frame which combines a modal frame and some relevance frames. A grafted model consists of a grafted frame and a truth-value assignment. In this paper, the grafted frame and the grafted model are constructed and used to show the completeness of S1. The implications of S1-completeness are discussed. A grafted frame does not combine two kinds of frames simply by putting relations defined in the components together. That is, the resulting grafted frame (...) is not in the form of $\langle W, R, R'\rangle$, or more generally, in the form of $\langle W, R, R', R'',...\rangle$, which consists of a non-empty set with several relations defined on it. Rather, it resembles the construction of fibering proposed by D. M. Gabbay and M. Finger. On a grafted frame, some modal worlds, which belong to the initial modal frame, are attached by some relevance frames. However, these two semantics have important differences. Consider the combined semantics involving semantics of relevance logic and modal logic. A fibred model and a grafted model proposed in this paper differ in the following respects. First, a fibred model is constructed from a class of modal models and a class of relevance models. A grafted model consists of a grafted frame and a truth-value assignment, where the grafted frame is constructed from a modal frame and some relevance frames, and the assignment is a union of a modal truth-value assignment V$_M$ and some relevance truth-value assignments V$_R$. V$_M$ defined in this paper is not the same as the assignment contained in a modal model. Second, in a fibred model each relevance world is associated with a modal model and each modal world with a relevance model. To be the grafted frame on which a grafted model is based, it is enough to have some modal worlds attached by some relevance frames. Moreover, no relevance world is associated with a modal frame in the grafted frame. Third, fibred models are intended to provide an appropriate semantics to combined logics. Grafted frames and grafted models are inspired to characterize S1, which, containing only one modality $\square$, is not a combined logic. It is shown in this paper that S1 is sort of a meta-logic of the intersection of S0.4 and F, where S0.4, a new system proposed in this paper, is in turn a meta-logic of the relevance logic. (shrink)

The use of neural transplantation to alleviate cognitive deficits is still in its infancy. We have an inadequate understanding of the deficits induced by different types of brain damage and their homologies in animal models against which to assess graft-induced recovery, and of the ways in which graft growth and function are influenced by factors within the host brain and the environment in which the host is operating. Further, use of fetal tissue may only be a transitory phase (...) in the search for appropriate donor sources. Nevertheless, findings from our laboratory and elsewhere have made a prima facie case for successful cognitive reconstruction by graft methods. (shrink)

Over the past two decades, research on neural transplantation in animal models of neurodegeneration has provided provocative in sights into the therapeutic use of grafted tissue for various neurological diseases. Although great strides have been made and functional benefits gained in these animal models, much information is still needed with regard to transplantation in human patients. Several factors are unique to human disease, for example, age of the recipient, duration of disease, and drug interaction with grafted cells; these need to (...) be explored before grafting can be considered a safe and effective therapeutic tool. (shrink)

The Classical Theory of function in the nervous system postulates that the nerve impulse is the result of a sequential reversal of the membrane potential due to an increased permeability of the membrane, first to sodium ions, then to potassium ions. The new theory presents a bio-physical model which depicts the nerve impulse as an event involving the motions of electrons and waves, and their interactions with sodium and potassium atoms and ions. The velocity of the nerve (...) impulse (the most important parameter of nerve function) is determined by the product of two constants: c = the speed of light, which is a constant for all nerves; k =a constant for each nerve and is believed to be a specific property of nerve matter related in some way to the atomic process. The theory proposes that the nerve impulse in the axon is dualistic in nature (particles and waves play equally significant roles). The dualistic nature accounts for the three most fundamental characteristics of conduction of the nerve impulse: periodicity (conduction of a nerve impulse over long distances with constant velocity and form); non-summing (two nerve impulses cannot be in the same place at the same time); quantum nature of each nerve impulse — i.e., the unit message of the nerve impulse is an indivisible unit. (shrink)

In Philip J. Ivanhoe’s introduction to his Readings from the Lu-Wang School of Neo-Confucianism, he argues convincingly that the Ming-era Neo-Confucian philosopher Wang Yang-ming (1472–1529) was much more influenced by Buddhism (especially Zen’s Platform Sutra) than has generally been recognized. In light of this influence, and the centrality of questions of selfhood in Buddhism, in this article I will explore the theme of selfhood in Wang’s Neo-Confucianism. Put as a mantra, for Wang “self-awareness is world-awareness.” My central image for this (...) mantra is the entire cosmos anthropomorphized as a doctor engaged in constant self-diagnosis, in which effort s/he is assisted by an entire staff of the nerves/nurses—individual humans enlightened as Wangian sages. In short, I will argue that the world for Wang could be meaningfully understood as a mindful, self-healing body within which humans are the sensitive nerves, using our mindful awareness to direct attention to the affected areas when injury or disease occurs. We are, and must thus recognize that we are, the bold but sensitive nervous system of the cosmos, sharing (like neurons) our loving excitement, carrying out (like a medical nurse) the doctor’s orders for the self-care of our cosmic body/medical corps. (shrink)

In the literature investigating the long history of appeals to ‘nature’, in its multiple meanings, for rules of conduct or justification of social order, little attention has been paid to a long-standing tradition in which medical and physiological arguments merged into moral and social ones. A host of medical authors, biologists, social writers and philosophers assumed that nature spoke its moral language not only in its general economy, but also within and through the body. This is why, for instance, many (...) critics of Malthus argued that physiological self-regulating mechanisms ensured a spontaneous adaptation of fertility to the circumstances. Beliefs in a beneficent economy of nature persisted when Providence was replaced by evolution. To some, they provided reasons for hope even when others worried about ‘unfit’ members of society increasing at a quicker rate than ‘fit’ ones. The nerves gradually replaced food and blood as moral mediators between society and the body. When faith in bio-social progress was shaken by degeneration theories, and fin de siècle anxiety concerned underpopulation rather than overpopulation, not an insignificant proportion of those who emphasised the bad effects of modern civilisation resorted to ideas and arguments based on a view of the body in which physiology and morality worked together. A common language and common assumptions linked the Kulturpessimisten to their optimistic eighteenth-century colleagues, in spite of their different forecasts. The present paper traces continuities and discontinuities in the operation of a persistent set of interrelated ideas and assumptions on the coalescence of the physiological and the moral across disciplines and contexts. (shrink)

Thomas Hobbes’ theory of punishment plays a constitutive role in the Leviathan’s theory of state sovereignty. Despite this, Hobbes’ justification for punishment is widely found to be discrepant, weak, inconsistent, and contradictory. Two dominant tendencies in the scholarship attempt to stabilize the Leviathan’s justification for the state’s right to punish by either identifying it with the sovereign’s right to war or by elaborating a theory of authorization within the state. In contrast, by tracing the deployments of the metaphor that Hobbes (...) utilizes to evoke the state’s right to punish in the Leviathan (i.e. that of the nerves of the Leviathan) this paper finds that these two accounts can be made to be consistent with each other — thereby destabilizing the grounds upon which the theory of punishment can be founded. (shrink)

In 1866, six Inuits were taken to the United States for the purpose of serving as specimens to American scientists at the Natural History Museum. Shortly after their arrival in New York, four of them had died. One of the survivors returned to the Arctic, while the sixth, Minik, now alone, fought to make possible the return of the remains of his dead companions to their village. Since the latter were being exhibited, as was then often the case (and happens (...) even today in many museums), in order to offer visitors examples of the Inuk people, Minik protested in vain. In 1909 he returned to Greenland when the scientists denied that the remains of his friends still existed. Several years later, still pursuing the issue, he went back to the United States to take up the fight against the bureaucracy for the repatriation of the bodies. He died in the United States in 1918. It was only in 1993 that he won out and that the remains of the four were returned to the Arctic homeland. (shrink)

In the literature investigating the long history of appeals to ‘nature’, in its multiple meanings, for rules of conduct or justification of social order, little attention has been paid to a long-standing tradition in which medical and physiological arguments merged into moral and social ones. A host of medical authors, biologists, social writers and philosophers assumed that nature spoke its moral language not only in its general economy, but also within and through the body. This is why, for instance, many (...) critics of Malthus argued that physiological self-regulating mechanisms ensured a spontaneous adaptation of fertility to the circumstances. Beliefs in a beneficent economy of nature persisted when Providence was replaced by evolution. To some, they provided reasons for hope even when others worried about ‘unfit’ members of society increasing at a quicker rate than ‘fit’ ones. The nerves gradually replaced food and blood as moral mediators between society and the body. When faith in bio-social progress was shaken by degeneration theories, and fin de siècle anxiety concerned underpopulation rather than overpopulation, not an insignificant proportion of those who emphasised the bad effects of modern civilisation resorted to ideas and arguments based on a view of the body in which physiology and morality worked together. A common language and common assumptions linked the Kulturpessimisten to their optimistic eighteenth-century colleagues, in spite of their different forecasts. The present paper traces continuities and discontinuities in the operation of a persistent set of interrelated ideas and assumptions on the coalescence of the physiological and the moral across disciplines and contexts. (shrink)

In the literature investigating the long history of appeals to ‘nature’, in its multiple meanings, for rules of conduct or justification of social order, little attention has been paid to a long-standing tradition in which medical and physiological arguments merged into moral and social ones. A host of medical authors, biologists, social writers and philosophers assumed that nature spoke its moral language not only in its general economy, but also within and through the body. This is why, for instance, many (...) critics of Malthus argued that physiological self-regulating mechanisms ensured a spontaneous adaptation of fertility to the circumstances. Beliefs in a beneficent economy of nature persisted when Providence was replaced by evolution. To some, they provided reasons for hope even when others worried about ‘unfit’ members of society increasing at a quicker rate than ‘fit’ ones. The nerves gradually replaced food and blood as moral mediators between society and the body. When faith in bio-social progress was shaken by degeneration theories, and fin de siècle anxiety concerned underpopulation rather than overpopulation, not an insignificant proportion of those who emphasised the bad effects of modern civilisation resorted to ideas and arguments based on a view of the body in which physiology and morality worked together. A common language and common assumptions linked the Kulturpessimisten to their optimistic eighteenth-century colleagues, in spite of their different forecasts. The present paper traces continuities and discontinuities in the operation of a persistent set of interrelated ideas and assumptions on the coalescence of the physiological and the moral across disciplines and contexts. (shrink)

Despite some clinical promise, using fetal transplants for degenerative and traumatic brain injury remains controversial and a number of issues need further attention. This response reexamines a number of questions. Issues addressed include: temporal factors relating to neural grafting, the role of behavioral experience in graft outcome, and the relationship of rebuilding of neural circuitry to functional recovery. Also discussed are organization and type of transplanted tissue, the of transplant viability, and whether transplants are really needed to obtain functional (...) recovery after brain damage. (shrink)

Cognitive dysfunction in Alzheimer’s disease is caused by disturbances in neuronal circuits of the brain underpinned by synapse loss, neuronal dysfunction and neuronal death. Amyloid beta and tau protein cause these pathological changes and enhance neuroinflammation, which in turn modifies disease progression and severity. Vagal nerve stimulation, via activation of the locus coeruleus, results in the release of catecholamines in the hippocampus and neocortex, which can enhance synaptic plasticity and reduce inflammatory signalling. Vagal nerve stimulation has shown promise (...) to enhance cognitive ability in animal models. Research in rodents has shown that VNS can have positive effects on basal synaptic function and synaptic plasticity, tune inflammatory signalling, and limit the accumulation of amyloid plaques. Research in humans with invasive and non-invasive VNS devices has shown promise for the modulation of cognition. However, the direct stimulation of the vagus nerve afforded with the invasive procedure carries surgical risks. In contrast, non-invasive VNS has the potential to be a broadly available therapy to manage cognitive symptoms in early AD, however, the magnitude and specificity of its effects remains to be elucidated, and the non-inferiority of the effects of non-invasive VNS as compared with invasive VNS still needs to be established. Ongoing clinical trials with healthy individuals and patients with early AD will provide valuable information to clarify the potential benefits of non-invasive VNS in cognition and AD. Whether invasive or non-invasive VNS can produce a significant improvement on memory function and whether its effects can modify the progression of AD will require further investigation. (shrink)

The transplantation of cholinergic neurons into the hippocampal formation has been well characterized. We describe our studies on the effects of cholinergic transplants in the retrosplenial cortex. These transplants were capable of ameliorating spatial navigation deficits in rats with septohippocampal lesions. In addition, we provide evidence for the modulation of transplanted neurons by the host brain.

The Latin translation of Sextus Empiricus’ ‘Outlines of Pyrrhonism’, published by Henri Estienne in 1562, are amongst the most influential texts in the history of scepticism. And yet, we still lack a complete and detailed study of their reception in modern times. Through investigation of the emblem on the frontispiece of the book, this paper argues that Estienne’s motivations for the publication should be interpreted as essentially anti-dogmatic and humanistic in nature. -/- .

Sham surgery is a controversial and rarely used component of randomised clinical trials evaluating surgical interventions. The recent use of sham surgery in trials evaluating efficacy of intracerebral fetal tissue grafts in Parkinson’s disease has highlighted the ethical concerns associated with sham surgery controls. Macklin, and Dekkers and Boer argue vigorously against use of sham surgery controls. Macklin presents a broad argument against sham surgery controls while Dekkers and Boer present a narrower argument that sham surgery is unnecessary in the (...) specific setting of fetal tissue engraftment for Parkinson’s disease. I defend sham surgery controls against both these criticisms. Appropriate clinical trial design, sometimes including sham surgery, is needed to ensure that false positive trial results do not occur and endanger public safety. Results of a completed trial of fetal tissue grafting for Parkinson’s disease are used to illustrate the potential benefits of, and problems associated with, sham surgery controls. Sham surgery controls, however, should be employed only when absolutely necessary. I suggest criteria for appropriate use of sham surgery controls. (shrink)

How does one testify and, moreover, testify philosophically to the experience of receiving an organ transplant? What kinds of survival or forms of living are being fostered by newly emerging conjunctions between philosophy and biomedicine? Focusing on transplantation and immunology, we are going to reflect on some of the ways and styles in which motifs drawn from these biomedical fields have come to occupy an increasingly prominent place in recent philosophy expressing and formulating different concerns and paradigms. Spurred on by (...) Francisco J. Varela and Jean-Luc Nancy's autobiographical reflections on transplantation, we are going to consider distinct moments and preoccupations at work in the motifs of immunity, autoimmunity, the pharmakon and the graft in the thought of Jacques Derrida, Roberto Esposito and Bernard Stiegler. (shrink)

Grafting embryonic brain tissue into the brain of patients with visual field loss due to cerebral lesions may become a method to restore visual function. This method is not without risk, however, and will only be considered in cases of complete blindness after bilateral occipital lesions, when other, risk-free neuropsychological methods fail.

We investigate the semantics of the logical systems obtained by introducing the modalities and into the family of substructural implication logics (including relevant, linear and intuitionistic implication). Then, in the spirit of the LDS (Labelled Deductive Systems) methodology, we "import" this semantics into the classical proof system KE. This leads to the formulation of a uniform labelled refutation system for the new logics which is a natural extension of a system for substructural implication developed by the first two authors in (...) a previous paper. (shrink)

Transpersonal agroecology (TPAE) is a theory, derived from the collective leanings of various important thinkers and practitioners in the field of alternative agriculture over the last century, which sees the mindset of the farmer to be just as important as his or her agricultural practices. However, these accumulated intuitions do not provide a coherent metaphysics within which to practice TPAE. Process metaphysics provides such a coherent framework for TPAE and for sustainable agriculture.

This article is about the beginnings of tissue culture-the culture of living, reproducing cells of complex organisms outside the body. It argues that Ross Harrison's experiments in nerve culture between 1907 and 1910 should be viewed as part of a larger shift in early twentieth-century laboratory practice from in vivo to in vitro experimentation. Via a focus on the temporality of experiment-contrasting the live object of Harrison's investigation with the static object of histological representations-this article details the production of (...) a new and surprising form of life, cellular life in vitro. Tissue culture, developed from Harrison's experiments, was greeted with great surprise and disbelief, despite Harrison's protestations that he had merely juxtaposed extant techniques. An analysis of these initial reactions to tissue culture illuminates the extent to which cells living visibly outside of the body in glass broke with in vivo practices and assumptions of the hiddenness and interiority of certain processes of growth and change. (shrink)

It is well established that neural grafts can exert functional effects on the host animal by a multiplicity of different mechanisms – by diffuse release of trophic molecules, neurohormones, and deficient neurotransmitters, as well as by growth and reformation of neural circuits. Our challenge is to understand how these different mechanisms complement each other.

It was thus the combination of observational and experimental approaches that ultimately led to confirmation of the outgrowth theory. The observational method was essential for defining various possible methods of nerve fiber development. The multicellular, protoplasmic bridge and outgrowth theories were each postulated to explain purely observational evidence. However, the lack of truly suitable equipment and techniques to study the developing nervous system made it impossible to agree on a single theory on this basis alone. The experimental method provided (...) a means of choosing between these theories. Without the preceding observations that had led to the formulation of various hypotheses, however, the experimental approach might not have been so successful, for the power of this method is more of selection than of generation.Therefore it is impossible to weigh separately the contributions of the observational and experimental approaches to the question of nerve fiber development. Both were necessary for the ultimate acceptance of the outgrowth theory. *** DIRECT SUPPORT *** A8402051 00004. (shrink)

Turning to the history of philosophical thought, I am surprised by the question what is knowledge? I am surprised because usually we do not reflect on our own knowledge; it appears to us as something obvious. And yet this question has disturbed people since the beginning philosophical thinlung. Moreover, at the time knowledge appeared as a subject full of aporiasintellectual difficulties and obvious contradictions of judgment. This led to the humiliating doubt that man could know anything about the world in (...) which he lived and, thus, exposed, so to speak, the painful nerve of the cognitive aspirations of human reason. (shrink)

The Doctrine of Specific Nerve Energies has been and continues to be enormously influential in the physiology, psychology, and philosophy of perception. In simple terms, the Doctrine states that we directly perceive in the first instance the activity of our nerves, rather than properties in the external world. The canonical early statement of the Doctrine by the physiologist Johannes Peter Müller had profound influence on both the phi- losophy and psychology of the 19th and early 20th centuries, especially as (...) reformulated and transmitted by Müller’s student Helmholtz. A common assumption of historical and ongoing debate about the Doctrine has been its supposedly idealist or skeptical implications. What is not commonly recognized is that Müller himself ad- vanced a realist interpretation along lines that would be recognized today as a form of epistemic structural realism. This paper analyzes Müller’s structuralist epistemology in detail and reconstructs his articulation and defense of the Doctrine of Specific Nerve Energies in its canonical form. Part II argues for the continued im- portance of the Doctrine and its structuralist interpretation for contemporary psychology, philosophy of per- ception, and history of philosophy of science. (shrink)

We investigate a recently devised polyhedral semantics for intermediate logics, in which formulas are interpreted in n-dimensional polyhedra. An intermediate logic is polyhedrally complete if it is complete with respect to some class of polyhedra. The first main result of this paper is a necessary and sufficient condition for the polyhedral completeness of a logic. This condition, which we call the Nerve Criterion, is expressed in terms of Alexandrov’s notion of the nerve of a poset. It affords a (...) purely combinatorial characterisation of polyhedrally complete logics. Using the Nerve Criterion we show, easily, that there are continuum many intermediate logics that are not polyhedrally complete but which have the finite model property. We also provide, at considerable combinatorial labour, a countably infinite class of logics axiomatised by the Jankov–Fine formulas of ‘starlike trees’ all of which are polyhedrally complete. The polyhedral completeness theorem for these ‘starlike logics’ is the second main result of this paper. (shrink)