A hypothesis about sensorimotor integration (the λ model) is described and applied to movement control and kinesthesia. The central idea is that the nervous system organizes positional frames of reference for the sensorimotor apparatus and produces active movements by shifting the frames in terms of spatial coordinates. Kinematic and electromyographic patterns are not programmed, but emerge from the dynamic interaction among the system s components, including external forces within the designated frame of reference. Motoneuronal threshold properties and proprioceptive inputs to (...) motoneurons may be cardinal components of the physiological mechanism that produces positional frames of reference. The hypothesis that intentional movements are produced by shifting the frame of reference is extended to multi-muscle and multi-degrees-of-freedom systems with a solution of the redundancy problem that allows the control of a joint alone or in combination with other joints to produce any desired limb configuration and movement trajectory. The model also implies that for each motor behavior, the nervous system uses a strategy that minimizes the number of changeable control variables and keeps the parameters of these changes invariant. Examples are provided of simulated kinematic and electromyographic signals from single- and multi-joint arm movements produced by suggested patterns of control variables. Empirical support is provided and additional tests of the model are suggested. The model is contrasted with others based on the ideas of programming of motoneuronal activity, muscle forces, stiffness, or movement kinematics. (shrink)

The basic concepts of motor control formulated in our target article were derived from specific experiments, a fact which is disregarded in Dalenoort's comments. A purely academic approach to motor control may not result in a clearer understanding of control concepts.

The cerebellum probably obeys the rules of sensorimotor integration common in the nervous system. One such a rule is formulated: the nervous system organizes spatial frames of reference for the sensorimotor apparatus and produces voluntary movements by shifting their origin points. We give examples of spatial frames of reference for different single- and multi-joint movements including locomotion and also illustrate that the process of motor development and learning may depend critically on the formation of appropriate frames of reference and the (...) organism's ability to manage them. We suggest that a solution to the problem of sensorimotor integration may not be trivial and may actually change the mental and experimental paradigms used in the understanding of the cerebellum and other brain structures, [HOUK et al.; SIMPSON et al.; SMITH; TIIACH]. (shrink)

The information required for perception may be available in the energy arrays that stimulate sensory organs but in a form not directly suitable for the planning and execution of the organism's actions in the environment. The requisite form of information is obtained, with no loss of adequate perception, by representation of sensory stimuli in frames of reference determined by internal control signals producing actions. This process seems evolutionarily advantageous but makes perception essentially non-direct, regardless of the degree of intra- or (...) inter-modal sensory integration. (shrink)

Understanding of the λ model has greatly increased in recent years as evidenced by most of the commentaries. Some commentators underscored the potential of the model to integrate aspects of different sensorimotor systems in the production of movement. Other commentators focused on not-yet-fully-developed parts of the model. A few persisted in misunderstanding some of its basic concepts, and on these grounds they reject it. In responding to commentaries we continue to elaborate on some fundamental points of the model, especially control (...) variables, the idea of movement production by shifting the positional frame of reference and the hypothesis of biomechanical correspondence in motor control. We also continue to develop our ideas on the intrinsic generation of the frame of reference associated with external space and utilized for the control of arm movement and locomotion. The dynamic principles underlying the model are discussed in light of the dynamical systems approach. (shrink)

Exclusively focused on data that are consistent with the proposed ideas, the target article misses an opportunity to review data that are inconsistent with them. Weaknesses of the emulation theory become especially evident when one tries to incorporate physiologically realistic muscle and reflex mechanisms into it. In particular, it fails to resolve the basic posture-movement controversy.

It is proposed here that Webb's ideas about robots as possible models of animals need some rethinking. In our view, even though widely used biorobotics strategies are fairly successful at reproducing the macroscopic behavior of biological systems, there are still several problems unresolved on the side of robotics as well as biology. Both mathematical and hardware-like robotics models should be feasible physiologically. Control principles elaborated in robotics are not necessarily applied to biological control systems. Although observations of flying birds inspired (...) aerodynamics and thus modern airplanes, little knowledge has been added to the neurophysiological principles underlying flight in birds. Chess playing computers might outperform most chess players, but they cannot be considered as physiologically feasible models of human thinking. (shrink)

The seeming absence of negative evidence in the input that children receive during language acquisition has long been regarded as a serious problem for non-nativist linguistic theories. Among the solutions that have been suggested for this problem, preemption by competing structures is doubtless the most intensively researched and widely accepted. However, while preemption works well in the domain of morphology, it cannot apply categorically in the domain of syntax, as this would preclude the existence of semantically overlapping constructions, such as (...) the ditransitive and the prepositional dative, which can be used alternatively with many, but not all, verbs of literal or metaphorical transfer. This paper investigates one specific version of preemption briefly entertained by Pinker (Language learnability and language development, Harvard University Pressm, 1984), which would account both for the existence of semantically overlapping constructions and for the fact that these constructions may preempt each other in the case of individual verbs. Typically, such pairs of grammatical constructions differ in their information-structural restrictions and speakers tend to choose the construction that best fits a given discourse context; when speakers use a construction even though there is an alternative that fits the discourse context better, children may take this as evidence that the alternative is not available for the specific verb in question. Two corpus studies are presented, comparing the information-structural profile of prepositional dative constructions containing verbs that may alternate between the dative and the ditransitive with the information structural profile of verbs that are restricted to the prepositional dative. For Pinker's preemptive mechanism to be feasible, there should be a clear and systematic difference in the information-structural profile of these two classes of verbs. However, no such difference can be found in actual usage. (shrink)

ExcerptWeak government is a negation of liberty.Francis LieberAfter the experiences of the past generation, it should be apparent that all too much of liberal internationalist thinking in America is not “internationalist” in any real sense at all. Internationalism, if it is to have any meaning as a word, must mean peace and cooperation between different nations, which by nature will have not merely different interests that must be reconciled but different political systems that must coexist.

À partir de l’observatoire d’une « consultation antialcoolique » ouverte en 1954 dans le 13e arrondissement de Paris, cet article étudie la manière dont le travail social a investi le nouveau champ d’action du suivi psychiatrique de l’alcoolisme, dans un contexte de mutations de la prise en charge médicale de cette maladie. Le contenu autant que la structure des dossiers de patients de la consultation, que nous mettons en regard avec des publications issues de revues médicales et de travail social, (...) permettent d’approcher le travail quotidien des assistantes sociales, au plus près des alcooliques et de leurs familles. Nous montrons que l’action de l’assistante sociale, devenue centrale bien que subordonnée à celle du médecin psychiatre, s’enrichit d’une dimension psychothérapique et se caractérise par la recherche de la confiance du malade et de son adhésion au traitement, marquant ainsi une inflexion nette dans le rapport aux populations assistées. Cependant, ces évolutions ne suffisent pas à débarrasser le travail social de ses ambiguïtés constitutives et notamment de ses fonctions de contrôle et de surveillance, sources de difficultés, de malentendus et de conflits avec les malades et leurs proches. (shrink)

At the end of the first book of Apollonius' Argonautica, Telamon accuses Jason of plotting to leave Heracles behind, an insult for which Telamon later apologizes. This article suggests that their reconciliation unites the Alexandrian interest in what is appropriate for epic with Aristotelian views on anger and political friendship, two themes that resonate throughout the poem. While Telamon's apology and Jason's moderate response revise the structure of traditional epic quarrels, the portrayal of self-control in this episode constitutes a moral (...) exemplar in keeping with those Homeric scenes that were admired by ancient philosophers. (shrink)

At the end of the 19th century, violent attacks by so-called anarchists gave the anarchist movement an increased amount of publicity. In the meantime, the success of “scientific socialism” promoted rationality to the rank of a new political doctrine. This article analyses the joint criticism of violence and materialism in the discourse of Gustav Landauer (1870-1919). The German philosopher and revolutionary made an original contribution to anarchism in theorising its incompatibility with violent means of action. He also made a crucial (...) move for the theory of ideas in affirming that reason was not the solution, but often the cause of violence. (shrink)

The presented article is an attempt to describe in a synthetic way an own vision of a German front-line soldier of the First World War. It also tries to show an image of some enemies – the French, the British and the Russians. The attempt was made on the basis of recollection material and literary forms created either during or soon after the war. The conclusion is unequivocal – the more contact the authors of the texts had with the opponent, (...) the more balanced image of the enemy they presented in their texts and the less were they prone to overestimate the German soldier. Yet the press material contained a lot of exaggeration. The authors created a haughty and sometimes even superhuman image of the German soldier. At the same time the image of the enemy was inhuman and deserving contempt. (shrink)

Il est courant d’attribuer au projet éducatif une finalité émancipatrice. Rien de moins évident pourtant que cette association, y compris sur un plan théorique. Le philosophe allemand Max Stirner (1806-1856), considéré par certains comme l’un des pères de l’anarchisme individualiste, fut le précurseur d’une pensée pédagogique radicale visant à favoriser l’émergence d’un moi autonome. Cet article analyse les fins et les modalités de l’éducation selon Stirner pour y relever certains paradoxes constitutifs du projet d’éducation émancipatrice. Il prolonge enfin l’analyse de (...) Stirner en envisageant ses déclinaisons pratiques pour la pédagogie contemporaine. (shrink)

S’appuyant sur les archives du Vorwärts des années 1890 et 1900, cet article analyse la fréquence symptomatique des références de l’organe du Parti social-démocrate allemand à Gustav Landauer, critique cinglant du socialisme marxiste qui entendait « donner au socialisme une nouvelle direction ». Il s’attache à déceler, dans ses dits et ses non-dits, la stratégie mise en œuvre par le Vorwärts de délégitimation de l’anarchisme et de monopolisation de la définition même du socialisme. Mais derrière l’entreprise de caricature et de (...) dénigrement, il montre aussi combien la controverse entre le Vorwärts et « l’inévitable Landauer » est révélatrice d’une série de désaccords structurels et fondamentaux sur la conception de l’histoire, de la société, de l’expérimentation et du changement social. (shrink)

This is the first complete, one-volume English translation of the ancient Chinese text Xunzi, one of the most extensive, sophisticated, and elegant works in the tradition of Confucian thought. Through essays, poetry, dialogues, and anecdotes, the Xunzi articulates a Confucian perspective on ethics, politics, warfare, language, psychology, human nature, ritual, and music, among other topics. Aimed at general readers and students of Chinese thought, Eric Hutton’s translation makes the full text of this important work more accessible in English than ever (...) before. Named for its purported author, the Xunzi has long been neglected compared to works such as the Analects of Confucius and the Mencius. Yet interest in the Xunzi has grown in recent decades, and the text presents a much more systematic vision of the Confucian ideal than the fragmented sayings of Confucius and Mencius. In one famous, explicit contrast to them, the Xunzi argues that human nature is bad. However, it also allows that people can become good through rituals and institutions established by earlier sages. Indeed, the main purpose of the Xunzi is to urge people to become as good as possible, both for their own sakes and for the sake of peace and order in the world. In this edition, key terms are consistently translated to aid understanding and line numbers are provided for easy reference. Other features include a concise introduction, a timeline of early Chinese history, a list of important names and terms, cross-references, brief explanatory notes, a bibliography, and an index. (shrink)

The socialist project is burdened by a history of brutal failures. The authors of the papers collected in this volume are convinced that a democratic and humane socialism is both desirable and possible. They lay out their view of different aspects of this new socialism in this book. Anatole Anton and Richard Schmitt are both the editors and contributors to this book. -/- Select chapters translated into Spanish have appeared in a volume in Barcelona, Spain.

O leitor encontrará, neste volume, o crítico e o pensador arrojado procurando destrinçar questões filosóficas como o irracionalismo, o homem e a técnica, temas políticos e culturais relacionados ao racismo e à atual cultural das gangs, bem como reflexões estéticas acerca da pseudo-arte e do kitsch, para integrá-los plenamente nos seus contextos filosóficos, sociais e humanos.