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In physiology, physics, mathematics, aesthetic theory and epistemology, Helmholtz intervened, and innovated. He contributed to the physiology of perception through work on the central nervous system, followed by work on optics and acoustics. He invented instruments, such as the opthalmoscope and introduced the mathematical principle of the conservation of energy to physics. For geometry, Helmholtz elaborated on the concept of an n-dimensional manifold. He secured the influence of the ‘Berlin physics’, introduced Faraday and Maxwell to Germany, refined the theory of electrodynamics and reflected on the role of discrete entities in physics. Having become the most influential representative of German science and its uncontested spokesperson, he repeated the importance of the connection between education and research and the necessity not to separate the natural sciences (Naturwissenschaften) from the social sciences (Geisteswissenschaften). This monumental body of work is experiencing a revival of interest today as historians of both science and culture consider it in a new light. But the question remains of how to characterize what we might call ‘the Helmholtz effect’ in philosophy. Why was Helmholtz equally influential not only on Cassirer, Husserl, Schlick, Meyerson and Freud, but also on the principal founders of contemporary physics; Einstein, Bohr and Heisenberg? To grasp this, we must understand the constant interaction between science and philosophy which characterized, even permitted, the extraordinary developments in mathematics, physics and physiology in Germany at that time. Here the connection between Helmholtz and Kant is fundamental, since ‘the Helmholtz effect’ transformed the Kantian heritage. Helmholtz did not write a systematic philosophical work, but in redefining fundamental epistemological concepts and constructing a large part of the conceptual structure in which both philosophy and relativistic and quantum physics developed during the early twentieth century, he modified the very problems of epistemology.

SUMMARY. — This paper aims to deal with the issue of what Pascal owes to the physics of Descartes. However, I shall not attempt to weigh Pascal's debt, making him just a disciple of Descartes. Rather I shall try to single out the difference there is between the two conceptions of the « principles of philosophy » that they advocate. It is only from such a point of view that one can understand why Pascal first opposes Descartes, while going on thinking differently. Pascal opposes Descartes inasmuch as he wants to secure the freedom of physics, metaphysical, epistemological and methodological. But then he moves on a very different ground. Indeed the style of Pascal's physics is not a deductive style, neither is it anything like « reading » the text of Nature, and finally it is not generated by a single autonomous mind. In this respect, Pascal allows the development of a totally new way of understanding Nature and physics, among the many others that the XVIIth century has forged., RÉSUMÉ. — L'objet de cet article est de proposer une analyse de ce que Pascal « doit » à la physique de Descartes. Toutefois il ne s'agira pas tant de mesurer une dette, comme si Pascal avait été un simple continuateur de Descartes, que de déterminer la différence qui oppose deux conceptions des « principes de la philosophie ». C'est de ce point de vue que l'on peut montrer comment Pascal pense d'abord contre Descartes, puis ailleurs que lui. Il pense contre Descartes en ceci qu'il veut assurer la liberté métaphysique, épistémologique et méthodologique de la physique. Il pense ailleurs que lui en ceci qu'il pratique une physique d'un genre tout différent : ostensive et non deductive, intervenante plutôt qu'assignée au décodage d'un « texte » déjà écrit, soumise enfin à la constitution d'une opinion dans une communauté, plutôt que solitaire. Pascal inaugure en cela une possibilité nouvelle de compréhension de la relation entre physique et philosophie, dont le XVIIe siècle offre tant d'interprétations distinctes., Chevalley Catherine. Ce que Pascal doit à la physique des Principia / What Pascal owes to the physics of the Principia philosophiae. In: Revue d'histoire des sciences, tome 58, n°1, 2005. pp. 9-27.

Immunologic reactions to protamine sulfate during cardiac surgery are very rare. The frequency and outcome of such adverse reactions is unclear. We report a case of lethal anaphylactic reaction to protamine that occurred in a non-diabetic patient following the uneventful replacement of the ascending aorta. We also briefly review the mechanisms of this adverse reaction and emit some considerations on the management of this situation.

Il y a sans doute en philosophie aujourd’hui peu de questions d’allure aussi classiques et academiques que celle du sujet. Pourtant, lorsqu’il s’agit de traiter des rapports entre philosophie, histoire des sciences et sociologie des sciences, le probleme que pose la determination d’un concept de sujet est generalement elude; ou bien, ce qui produit le meme neant de resultats, il est phagocyte par la polemique ou noye dans l’œcumenisme. Je voudrais donc proceder autrement et affronter directem...

Using the example of the difficulties which emerge when trying to model complex behaviors – such as emotional expression – that result from stochastic interactions between different components, we argue that biorobotics may well describe one possible evolution of certain features of a biological system, but cannot pretend to be a simulation of the whole behavior of the system.

Acute lung injury (ALI) may complicate thoracic surgery and is a major contributor to postoperative mortality. We analyzed risk factors for ALI in a cohort of 879 consecutive patients who underwent pulmonary resections for non-small cell lung carcinoma. Clinical, anesthetic, surgical, radiological, biochemical, and histopathologic data were prospectively collected. The total incidence of ALI was 4.2% (n = 37). In 10 cases, intercurrent complications (bronchopneumonia, n = 5; bronchopulmonary fistula, n = 2; gastric aspiration, n = 2; thromboembolism, n = 1) triggered the onset of ALI 3 to 12 days after surgery, and this was associated with a 60% mortality rate (secondary ALI). In the remaining 27 patients, no clinical adverse event preceded the development of ALI-0 to 3 days after surgery-that was associated with a 26% mortality rate (primary ALI). Four independent risk factors for primary ALI were identified: high intraoperative ventilatory pressure index (odds ratio, 3.5; 95% confidence interval, 1.7-8.4), excessive fluid infusion (odds ratio, 2.9; 95% confidence interval, 1.9-7.4), pneumonectomy (odds ratio, 2.8; 95% confidence interval, 1.4-6.3), and preoperative alcohol abuse (odds ratio, 1.9; 95% confidence interval, 1.1-4.6). In conclusion, we describe two clinical forms of post-thoracotomy ALI: 1). delayed-onset ALI triggered by intercurrent complications and 2). an early form of ALI amenable to risk-reducing strategies, including preoperative alcohol abstinence, lung-protective ventilatory modes, and limited fluid intake.In an observational study including all patients undergoing lung surgery, we describe two clinical forms of acute lung injury (ALI): a delayed-onset form triggered by intercurrent complications and an early form associated with preoperative alcohol consumption, pneumonectomy, high intraoperative pressure index, and excessive fluid intake over the first 24 h.

IN the perioperative period, anaphylactic reactions are often induced by the intravenous administration of muscle relaxants, antibiotics, colloids, and radiocontrast materials as well as after local contact with latexcontaining materials (e.g., gloves, catheters, airway tube) and chlorhexidine. Inhalation of toxic and highly irritant substances contained in cleaning solutions has occasionally been incriminated to produce acute bronchospasm and hypersensitization to other allergens. In this report, the postoperative onset of bronchospasm, hypotension, and urticaria is described and the involvement of both immune and nonimmune mechanisms is discussed.

We analyzed a local database including 468 consecutive patients who underwent elective aortic abdominal surgery over an 8-yr period in a single institution. A new cardioprotective perioperative protocol was introduced in January 1997, and we questioned whether perioperative cardiac outcome could be favorably influenced by the application of a stepwise cardiovascular evaluation based on the American College of Cardiology/American Heart Association guidelines and by the use of antiadrenergic drugs. Clonidine was administered during surgery, and beta-blockers were titrated after surgery to achieve heart rates less than 80 bpm. We compared data of two consecutive 4-yr periods (1993-1996 [control period] versus 1997-2000 [intervention period]). Implementation of American College of Cardiology/American Heart Association guidelines was associated with increased preoperative myocardial scanning (44.3% vs 20.6%; P0.05) and coronary revascularization (7.7% vs 0.8%; P0.05). During the intervention period, there was a significant decrease in the incidence of cardiac complications (from 11.3% to 4.5%) and an increase in event-free survival at 1 yr after surgery (from 91.3% to 98.2%). Multivariate regression analysis showed that the combined administration of clonidine and beta-blockers was associated with a decreased risk of cardiovascular events (odds ratio, 0.3; 95% confidence interval, 0.1-0.8), whereas major bleeding, renal insufficiency, and chronic obstructive pulmonary disease were predictive of cardiac complications. In conclusion, cardiac testing was helpful to identify a small subset of high-risk patients who might benefit from coronary revascularization. Sequential and selective antiadrenergic treatments were associated with improved postoperative cardiac outcome.Implementation of American College of Cardiology/American Heart Association guidelines and use of antiadrenergic drugs were associated with better cardiac outcomes after major vascular surgery.

Coronary artery disease is occasionally encountered in lung transplant recipients and is a risk factor for perioperative complications and poor survival. Besides combined heart-lung transplantation, various techniques of myocardial revascularization can be performed before, or at the time of lung transplantation. We report herein a patient with end-stage bronchoemphysema and two-vessel coronary disease who underwent 'off-pump' coronary artery bypass graft immediately followed by bilateral lung transplantation.

To describe the evolution of the perioperative management of myasthenia gravis (MG) patients undergoing thymectomy and to question the need for systematic postoperative ventilation. We collected data retrospectively from 36 consecutive MG patients who underwent thymectomy over a 21-yr period, via transthoracic, -cervical or -sternal incisions (n = 5,n=7,n=24, respectively). From 1980 to 1993, a balanced anesthetic technique (n=24) included various inhalational agents with opiates and myorelaxants (in eight cases); 22 patients were admitted to the intensive care unit (ICU). Since 1994,iv propofol was combined with epidural bupivacaine and sufentanil (n= 12); all patients were admitted to the postanesthesia care unit. Short-term postoperative ventilation (median time four hours, range from three to 48 hr) was required in eight patients who had longer hospital stay (median stay= 12 days, range (8–28)vs five days (4–15) for patients with early extubation, P < 0.05) but similar clinical improvement six months after thymectomy. Postoperative ventilatory support was required more frequently when a balanced anesthetic technique was used (odds ratio=4.2 (1.1–9.7),P=0.03) and particularly when myorelaxants were given (odds ratio= 13.9 (2.1–89.8),P=0.009). Leventhal’s scoring system had low sensitivity (22.2%) and positive predictive values (25%). Our data show that the severity of MG failed to predict the need for postoperative ventilation. A combined anesthetic technique was a safe and cost-effective alternative to balanced anesthesia as it provided optimal operating conditions and resulted in fewer admissions in ICU and shorter hospital stays.

Aortic dissection is the most common acute disease involving the ascending aorta and carries a high mortality rate if surgical therapy is not initiated rapidly following the onset of symptoms. Therefore, timely recognition of this disease entity coupled with urgent and appropriate management is the key to a successful outcome. We describe a patient with aortic dissection extending into the right coronary artery (RCA) who was successfully resuscitated and operated on following a cardiac arrest during transfer to the operating room.

My contribution will focus on only one question, which I would like to state in the simplest possible way. This question will be: why do we find Bohr obscure? Or, alternatively, why is there so much — and ever renewed — complaint in the literature over Bohr ‘being unintelligible’?

What do we mean, from a philosophical point of view, when we compare physics and art? This is, in its most general form, the issue which I shall address here. Clearly, contemporary philosophy gives much credit to the idea that science and art are not essentially different activities. For instance, for Goodman and Elgin the affinities between art, science and perception make their respective philosophies appear as different guises of a “general theory of knowledge” in which the concept of symbol plays a crucial part;1 van Fraassen repeatedly hints at the similarities between the “joint enterprises of philosophy of art, of law, of religion and of science”;2 and Hacking has recently suggested that the idea of “styles of reasoning” can be developed in new ways in the philosophy of science.3 The idea of an essential affinity between physics and art is undoubtedly attractive, and closely involved with contemporary shifting conceptions of the nature of physics and the nature of art. Yet its presuppositions and implications are not obvious: What conception of knowledge do we implicitly have in mind when we make a comparison between art and science? More particularly, what conception of science and what of art?

This volume is the first in a projected series devoted to the mathematical and philosophical works of the late Claude Chevalley. It covers the main contributions by the author to the theory of spinors. Since its appearance in 1954, "The Algebraic Theory of Spinors" has been a much sought after reference. It presents the whole story of one subject in a concise and especially clear manner. The reprint of the book is supplemented by a series of lectures on Clifford Algebras given by the author in Japan at about the same time. Also included is a postface by J.-P. Bourguignon describing the many uses of spinors in differential geometry developed by mathematical physicists from the 1970s to the present day. An insightful review of "Spinors" by J. Dieudonne is also made available to the reader in this new edition.

In a little-known paper published one month before his major article on complementarity and the interpretation of quantum mechanics, Niels Bohr made some comments about the influence of philosophy on the genesis of quantum theory. The main line of his argument went as follows. The connection between philosophy and the natural sciences was not only met, he said, at the earliest stages of science, but it was also a permanent one: “Cross-fertilization has taken place during the entire development of science up to recent times, where the vast accumulation of empirical data in all fields and the high standards of methods required for the acquisition and analysis of the data have necessitated extensive specialization in science”. Such a cross-fertilization occurred each time physics was faced with problems “which call for a revision of The concepts underlying our understanding of observations Then, clearly pointing to quantum mechanics, Bohr added that it had been of “inestimable significance that scientists were able to find support and points of departure for new advances in the endeavors of philosophers to make clear the foundation and limits of human intellectual activity”, and that these endeavors were passed on to scientists “through the formation of words which embodies the thought of these philosophers and had now become part of the common language”.1

How should we read Bohr? The answer to this question is by no means clear, not least because for a long period of time Bohr has not been read but rather mythologized, and his views “almost universally either overlooked or distorted beyond recognition” (Hooker 1972, 132). Even among his readers, though, there is a general feeling of uneasiness with respect to his use of words, and wide disagreement with respect to what he really meant to say. This seems to have always been the case, if we recall what Ehrenfest wrote to Bohr on July 17, 1921: “Now, dear Bohr, every person I know wails only over the fact that you write your things so briefly and compactly that one always has the greatest trouble fetching all of the ideas out of the fruit cake” (Works, 3, 623). Ehrenfest’s remark suggests that our predicament with Bohr’s thought originates in fact in his own style of writing; and accordingly, the many stories told in the doxography about Bohr’s mumbling unintelligible remarks or his endlessly rewriting each of his papers seem to point to some accidental and subjective characteristics of his: he had no deep professional knowledge of the language of philosophy, not enough time, or too much anxiety. But we could also look at Bohr’s struggle with language the other way around, in a very different way. Heisenberg, for instance, noted several times that Bohr was in the process of creating ‘a new language’.

On examine l’imbrication des aspects scientifiques et philosophiques de l’objectivite telle qu’elle apparait dans un texte tardif de Niels Bohr (des armees cinquante), comme aboutissement dans sa pensee de ses essais toujours repris de redefinition de cette notion, en rapport a un renouvellement de la pensee de la separation sujet-objet.

De maniere de plus en plus evidente, les sciences s'efforcent aujourd'hui de fonnuler et d'elaborer les questions philosophiques et historiques qu'elles posent. Cette ouverture a un effort de pensee qui ne soit ni ponctuel ni decoratif ni simplement auto-reflexif exige, nous semble-t-il, afin que l'analyse soit egalement attentive aux resultats et a I'ensemble des pratiques qui les ont rendus possibles, la reunion d'approches rigoureuses formees dans des champs disjoints: ceux des sciences, de l'histoire et de la philosophie. Dans le but de favoriser ce travail comrnun, nous avons cree l'Association Henri Poincare pour l'histoire et la philosophie des mathematiques et de la physique modemes (HPMP). Cette association se concentre, comme son nom l'indique, sur les sciences des xrxs et xxe siecles et elle est ouverte atoute personne interessee par cette periode. II va sans dire que, si chacun de nous a, quant a la nature precise de son inquietude intellectuelle, des idees bien formees, I'Association n'a pas d'orientation doctrinale. Nous chercherons done une forme de vie intermediaire entre la radicalite ephemere des Manifestes et l'insignifiance durable des consensus. Nos projets ont concerne et concernent, dans l'irnmediat, d'une part, l'organisation de Journees et de Colloques sur des questions qui engagent une interpretation a la fois technique, historique et philosophique et, d'autre part, la constitution d'archives ecrites et orales sur I'Ecole mathematique francaise. Nous souhaitons a plus long terme susciter et soutenir l'edition francaise de textes fondamentaux, reflechir aux problemes de documentation en histoire des mathematiques et de la physique, enfin contribuer a accentuer Ie role specifique que l'histoire et la philosophie des sciences nous paraissent devoir jouer dans la diffusion des savoirs.

L'optique prenewtonienne fait du probleme de la nature de la lumiere et du genre de realite physique des images visuelles un enjeu essentiel. Dans les developpements ulterieurs, ces deux questions se trouvent peu a peu videes de signification et disparaissent au profit de l'expose des proprietes de la lumiere. L'optique n'est plus associee ouvertement a des considerations theologiques, ni a ces modeles cosmologiques cons truits comme des commentaires de la Genese dont elle etait l'expression traditionnelle. Perdant sa preeminence, elle devient un element d'une theorie generale du monde qui se presente comme une physique mathe matique. Mais la facilite de cette scission avec les problemes ontologiques n'est qu'une illusion recurrente. Si l'optique met, de fait, longtemps a se determiner comme une science particuliere, c'est qu'elle doit rompre pour cela ses liens avec la theologie, la peinture, la medecine, la theorie de l'âme et de ses affections. Par ailleurs, la persistance jusqu'a la fin du xvne siecle, et notamment dans l'optique des Jesuites, d'une theorie de la lumiere a la fois rationaliste, neo-platonicienne, alchimisante et experimentale, montre bien, a contrario, la difficulte de la decision qui, chez Newton comme deja chez Descartes et Pascal, et deja chez Galilee, renvoie dans l'indecidabilite le probleme de la nature de la lumiere, c'est-a-dire de son genre de realite. Gomment faire apparaitre l'etendue des embarras qui etaient ainsi

SUMMARY. — The notion of Complementarity, put forward by Bohr when the new « quantum mechanics » was first publicly discussed, is almost invariably presented as a superficial, and ill-defined, means of resolving fundamental difficulties — by contributing to the obfuscation of, and evasion from, these issues. This paper seeks to show that, on the contrary, the Copenhagen Interpretation — taking Complementarity as a central concept — was addressing the whole, complex, question of the relationship between natural language and physical objects : in this case, the so-called « atomic phenomena ». This problem entailed a paradox, which in turn led to distinguishing two notions of physical reality, calling for scrupulous definition. In such a context, complementarity takes on the role of an indispensable, if imperfect safeguard, as to the consistency of the « ordinary » (i.e. unformalized) discourse of physics. It acts to compensate for the unattainability of a quantum language, in adequation to objects that no longer behave as do the objects in our ordinary world., RESUME. — La notion de Complémentarité proposée par Bohr en 1927, au moment de la première discussion publique de la nouvelle « mécanique quantique », est presque toujours présentée comme la solution mal définie et superficielle de difficultés fondamentales, qu'elle contribuerait à éluder. L'objet de cet article est de montrer, au contraire, que l'Interprétation de Copenhague, pour laquelle la Complémentarité est un concept central, posait dans toute sa complexité le problème de la relation du langage naturel aux objets de la physique, désignés par le terme de « phénomènes atomiques ». C'est ce problème qui donne lieu à un paradoxe, qui à son tour engendre une distinction entre deux notions de réalité physique, qu'il faut définir soigneusement. Dans ce contexte, la complémentarité devient une sorte de garantie, imparfaite mais nécessaire, de la cohérence du discours ordinaire (non formalisé) de la physique. Elle compense l'impossibilité de trouver un langage quantique adéquat à des objets qui ne se présentent plus comme des choses du monde ordinaire., Chevalley Catherine. Complémentarité et langage dans l'interprétation de Copenhague. In: Revue d'histoire des sciences, tome 38, n°3-4, 1985. pp. 251-292.

In his 1934 paper entitled “Transformations of the foundations of natural science”1 Heisenberg stressed the possibility for physical theories to “exhibit a structure different from the structure of classical physics”. This, he said, would happen in the one case when their objects would not be any more “things encountered in a direct and immediate experience”2: to leave this field ruled by classical physics would thus generate a break, a change, a shift in the very structure of the physical theory. The “mimetic” relationship between the objects of the theory and the objects of our world would be lost and would not ensure any more the truth value of the propositions of natural science.

— Albert LautmarCs philosophy of science is rooted in his experience of German mathematics and physics at the beginnings of the 1930's. His view, which is strictly opposed to the one of the Vienna Circle, is to take into consideration scientific theories as totalities and to provide an exegesis of the links which exist between the technical procedures and the structural meaning of the abstract ideas expressed by them. Lautman finds the unity of science — and especially the unity of modern algebra and quantum physics — in the « logical worries » from which science emerges. By doing so, however, he creates for himself the constraint of explaining in metaphysical terms why the ideal reality is revealed in a plurality of historical theories, and this leads him to difficulties which are not solved inside his work., Résumé. — La philosophie des sciences d'Albert Lautman prend source dans son expérience des mathématiques et de la physique allemandes du début des années 1930. Le projet de Lautman, opposé par lui-même point par point à celui du Cercle de Vienne, est de prendre en considération les théories scientifiques constituées, et de les soumettre à un commentaire de l'intérieur qui puisse révéler les liaisons entre les techniques mises en œuvre et la signification structurale des idées abstraites qui s'y expriment. En choisissant de trouver l'unité de la science — et notamment celle de l'algèbre moderne et de la physique quantique — dans l'unité des « soucis logiques » qui la déterminent. Lautman se contraint cependant à penser le problème métaphysique de la pluralité et de l'historicité des théories dans lesquelles se révèle la réalité idéale, ce qui le conduit à des difficultés que son œuvre, inachevée, ne résout pas., Chevalley Catherine. Albert Lautman et le souci logique. In: Revue d'histoire des sciences, tome 40, n°1, 1987. Mathématique et philosophie : Jean Cavaillès et Albert Lautman. pp. 49-77.