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It has become something of a platitude to say that sharp, continuous increases in prices are one of the most serious economic problems of our time. Indeed, the problem is so great, we are told, that unless it is brought under control inflation will destroy the very fabric of the ‘Western’, ‘industrial’ or ‘civilized’ society — the exact scale of the ‘destruction’ depending on the author’s capacity (or predilection) for taking a ‘cosmic’ view of such momentous happenings.

pas de résumé; no summary

Flatness has been already well defined and widely studied for finite dimensional dynamical systems. One of the remarquable consequences of this property is to allow parametrization of trajectories (both state and control) by free functions and their derivatives. It therefore provides an easy solution to an important problem in control theory : motion planning. For linear finite dimensional systems, flatness is exactly equivalent to controllability, via the Brunovsky canonical decomposition. This work proposes a definition of flatness for a class of infinite dimensional systems and extends Brunovsky canonical decomposition to infinite dimension. Following this new definition, the problem of flatness for a general linear 1-D diffusion equation is completely studied. A method allowing the effective computation of flat trajectories is given, and the canonical nature of this representation of trajectories is proved. Other example are studied, including the linear Kortewerg De Vries 1-D equation and a 2-D diffusion equation, which shows that the method is applicable to a wide range of problems.; La notion de platitude aété bien définie et largement étudiée pour les systèmes dynamiques de dimension finie. Une des conséquences marquantes de cette propriété est de permettre la paramétrisation des trajectoires (état et commande) par des fonctions libres et leurs dérivées, rendant ainsi aisée la solution d'un problème important en contrôle des systèmes dynamiques: la planification de trajectoires. Pour les systèmes linéaires de dimension finie, on a coïncidence exacte entre platitude et commandabilité, via la mise sous forme de Brunovsky. La possibilité de définir une notion convenable de platitude en dimension infinie, et d'étendre la notion de forme de Brunovsky à certaines classes de systèmes de dimension infinie est examinée, et une définition de la platitude est proposée pour ces systèmes. L'étude de la platitude de l'équation générale de diffusion à une variable d'espace est complètement traitée. Une méthode d'obtention d'une paramétrisation d'une famille dense de trajectoires est proposée, et la canonicité de la représentation de ces trajectoires est démontrée. Divers cas d'étude sont proposés, avec des applications à la planification de trajectoires. L'étude complète de l'équation de Korteweg-De Vries mono-dimensionnelle linéaire est réalisée, ainsi que celle d'un problème de diffusion à deux variables d'espace, montrant les possibilités d'extension de la méthode à un cadre beaucoup plus général.

Flatness has been already well defined and widely studied for finite dimensional dynamical systems. One of the remarquable consequences of this property is to allow parametrization of trajectories (both state and control) by free functions and their derivatives. It therefore provides an easy solution to an important problem in control theory : motion planning. For linear finite dimensional systems, flatness is exactly equivalent to controllability, via the Brunovsky canonical decomposition. This work proposes a definition of flatness for a class of infinite dimensional systems and extends Brunovsky canonical decomposition to infinite dimension. Following this new definition, the problem of flatness for a general linear 1-D diffusion equation is completely studied. A method allowing the effective computation of flat trajectories is given, and the canonical nature of this representation of trajectories is proved. Other example are studied, including the linear Kortewerg De Vries 1-D equation and a 2-D diffusion equation, which shows that the method is applicable to a wide range of problems., La notion de platitude aété bien définie et largement étudiée pour les systèmes dynamiques de dimension finie. Une des conséquences marquantes de cette propriété est de permettre la paramétrisation des trajectoires (état et commande) par des fonctions libres et leurs dérivées, rendant ainsi aisée la solution d'un problème important en contrôle des systèmes dynamiques: la planification de trajectoires. Pour les systèmes linéaires de dimension finie, on a coïncidence exacte entre platitude et commandabilité, via la mise sous forme de Brunovsky. La possibilité de définir une notion convenable de platitude en dimension infinie, et d'étendre la notion de forme de Brunovsky à certaines classes de systèmes de dimension infinie est examinée, et une définition de la platitude est proposée pour ces systèmes. L'étude de la platitude de l'équation générale de diffusion à une variable d'espace est complètement traitée. Une méthode d'obtention d'une paramétrisation d'une famille dense de trajectoires est proposée, et la canonicité de la représentation de ces trajectoires est démontrée. Divers cas d'étude sont proposés, avec des applications à la planification de trajectoires. L'étude complète de l'équation de Korteweg-De Vries mono-dimensionnelle linéaire est réalisée, ainsi que celle d'un problème de diffusion à deux variables d'espace, montrant les possibilités d'extension de la méthode à un cadre beaucoup plus général.

The work presented here stands in the field of control of systems. It relies on the recent theory of flatness. We present industrial realizations in process control and theoretical results in the field of partial differential equations. At first we detail four industrial applications developed in collaboration with TotalFinaELF. The obtained results underlines the relevance of our flatness-based approach in process control: achievement of large transients, explicit handling of nonlinearities, delays, constraints... Then we consider several physical systems ruled by wave equations. Writing these equations and their boundary conditions as delay systems, we give an explicit parametrization of their trajectories. This shows the flatness of these systems and provides a constructive proof of their controllability. All these examples, where delays play different roles, enlighten both the practical and theoretical importance of the flatness property in the fields of process control and wave equations.; Le travail s'inscrit dans le cadre de la platitude, théorie récente dans le domaine du contrôle des systèmes. Nous présentons des réalisations industrielles en génie des procédés et des contributions théoriques dans le domaine des équations aux dérivées partielles. A partir d'applications industrielles réalisées avec le groupe TotalFinaElf et aujourd'hui en service dans les usines concernées, nous montrons l'intérêt pratique de la platitude dans le domaine du contrôle des procédés : gestion de grands transitoires, prise en compte explicite des non linéarités, des retards, des contraintes. Nous traitons ensuite un ensemble d'exemples physiques de systèmes régis par des équations des ondes. En réécrivant ces équations aux dérivées partielles et leurs conditions limites comme des équations à retards, nous exhibons une paramétrisation de leurs trajectoires établissant ainsi la propriété de platitude de ces systèmes. Il est alors possible de prouver de maniéré constructive la commandabilite de ces systèmes en calculant des trajectoires entre différents états. Tous ces exemples, ou les retards jouent des rôles à chaque fois différents, nous permettent de mettre en valeur l'importance pratique et théorique de la propriété de platitude dans le domaine du génie des procédés et du contrôle des équations des ondes.

National economies have become far more integrated and interdependent than they were only thirty years ago. Over the last two decades, the term ‘global’ began to be used in various phrases (e.g., ‘the global economy’ or ‘the global marketplace,’ and on the cultural front, Marshall MacLuhan coined the phrase ‘the global village’ back in the 1960s). Globalization itself became the fashionable platitude of the 1990s. Indeed, globalization is treated either as a convenient catchword alluding to a myriad of discrete changes or, as an explanatory concept, it is shorthand for a new theory of capitalistic development at the eve of the new millennium. It is either trite or mythical.

This work propose a systematic approach for robust tracking control design of a class of nonlinear systems, well known as dynamic flat systems. For such system the path planning is easy, due to the fact that a flat system is equivalent to a linear system by using a diffeomorphism and a feedback loop. However, this approach is available only for one model and without any disturbances. For a set of model and with exogenous disturbances, the use of a linear regulator designed by optimization of an appropriate cost function insure the tracking objective. A two-degree-of-freedom scheme is used to clarify the design objectives with a complete partition between the nominal tracking and the robust tracking objectives. This approach is applied to the design of robust control of a synchronous machine., Ce travail propose une méthodologie de synthèse de loi de commande robuste pour les systèmes dynamiques plats. La génération de trajectoires de référence est simple à mettre en oeuvre pour un système plat car il est équivalent à un système linéaire par difféomorphisme et bouclage. Cependant cette démarche n'est valable que pour un modèle, et en l'absence de perturbations. Pour une famille de modèles, et en présence de perturbations exogènes, le suivi de trajectoire défini à partir du modèle nominal est garanti par un régulateur linéaire synthétisé par optimisation de critères. L'utilisation d'un schéma à deux degrés de liberté générique permet de poser clairement le problème de synthèse en séparant les objectifs de poursuite nominale et les objectifs de régulation et de poursuite robustes. Cette démarche est ensuite appliquée à la synthèse d'une loi de commande robuste d'une machine synchrone.

Analisaremos a comédia O caminho da porta, de Machado de Assis, a partir da proposição de Cecília Loyola, para quem o teatro machadiano nos oferece aparatos realistas — como os cenários e o prosaísmo das situações que motivam o enredo — mas retira-lhes a estabilidade da estrutura nuclear, que substitui por outra, múltipla e movediça. Um exemplo dessa retirada de estabilidade seria a proposta machadiana de um raisonneur deliberadamente desacreditado, que significa um afastamento considerável em relação à estrutura realista., We will analyze the comedy O caminho da porta, by Machado de Assis, from the perspective of Cecilia Loyola, for whom the author’s dramatic productions offer us realistic apparatuses — like the scenarios and the platitude that motivates the plot — but withdraw their stability, replacing the nuclear structure by an different one, multiple and slippery. An example of this new structure would be Machado’s use of the raisonneur, character that, in this play, is deliberately discredited, which means a considerable dismissal in relation to the realist structure.

Mind and environment evolve in tandem—almost a platitude. Much of judgment and decision making research, however, has compared cognition to standard statistical models, rather than to how well it is adapted to its environment. The author argues two points. First, cognitive algorithms are tuned to certain information formats, most likely to those that humans have encountered during their evolutionary history. In par ticular, Bayesian computations are simpler when the information is in a frequency format than when it is in a probability format. The author investigates whether fre quency formats can make physicians reason more often the Bayesian way. Second, cognitive algorithms need to operate under constraints of limited time, knowledge, and computational power, and they need to exploit the structures of their environments. The author describes a fast and frugal algorithm, Take The Best, that violates standard principles of rational inference but can be as accurate as sophisticated "optimal" mod els for diagnostic inference. Key words: Bayes' theorem; bounded rationality; infor mation format; probabilistic reasoning; satisficing; training; medical education. (Med Decis Making 1996;16:273-280)

“Seeing is believing,” they say. This hoary bromide suggests a common belief in the importance of perception-especially visual perception-in the acquisition of knowledge. This is not just a platitude about how we form beliefs about the world, beliefs which might be true or false. It is rather a sort of folk testimony to the importance of visual evidence in confirming, as well as acquiring, hypotheses, conjectures or beliefs. Of course sometimes things are not as they seem. Visual illusion, hallucination, tromp l’oeil and other “tricks of the eye” are well familiar, but typically are not taken to suggest anything like a sort of general skepticism about visual perception. Such problems are seen more as pointing to boundary conditions for the fidelity of direct visual perception than as counter-examples to it.

Is “database theory” an oxymoron? Or is ata platitude? What is the fitness measure that decides the surviva! of ideas (and areas) in mathematics, in applted science, and in computer science? Which ideas from database theory during the past twenty-five years have influenced research in other fields of computer science? How many were encapsulated in actual products? Was the relational model the on[y true paradigm sh@ m computer science ? Is applicability the only and ultimate justification of theoretical research in an applied science? Are applicability pressures rea!ly exogenous and unwelcome? Are negattve results appropriate goals of theoretical research in an appiied science —or are they the on[y possibie such research goals? If scientific theories must be refutab!e, what are the “hard facts” that provide the possibility of refutation in the case of database theory?

By starting from uncontroversial commonplaces or platitudes philosophers may arrive at a profound disagreement over fundamental issues. In his criticism of psychologism Frege makes the innocuous point that being true is different from being taken to be true. Neither error nor discovery would be conceivable otherwise.’ Davidson makes the same point by claiming that the notion of belief involves the notion of objective truth.2But Dummett has claimed that Frege is “the very archetype of a realist” and takes his remark as an “affirmation of his realist stance”3while Davidson has been considered to be an idealist who, by starting from Convention T and expanding the notion of translation to that of “translation into a language we know” — a small, but significant expansion! — identifies what can be true with what we can understand.4Thus, the disagreement between a realist and an idealist doesn’t exclude that they accept the same platitude. Where does the disagreement come from? It may be that it is due rather to the use philosophers make of the platitudes than to the platitudes themselves.

This thesis introduces the new concept of flatness. A system is differentially flat (or simply flat) if its behaviour can be completely described by a set of differentially independant functions depending on the system variables and their derivatives: any trajectory of the system can be recovered from the knowledge of this set of functions without integrating differential equations. Flatness is defined through an equivalence relation, called equivalence by endogenous feedback. Two systems S and T are equivalent if there exists a bijective correspondance between trajectories of S and trajectories of T. A flat system is by definition equivalent to a system "without dynamics", that is a set of arbitrary functions.; On introduit dans cette thèse le concept nouveau de platitude. Un système est différentiellement plat (ou plus simplement plat) si son comportement peut être complètement décrit par un ensemble de fonctions différentiellement indépendantes dépendant des variables du système et de leurs dérivées : toute trajectoire du système peut s'obtenir à partir de cet ensemble de fonctions sans intégrer d'équations différentielles. La platitude se définit par l'intermédiaire d'une relation d'équivalence. Deux systèmes S et T sont équivalents s'il existe une correspondance bijective entre les trajectoires de S et celles de T. Par définition, un système est plat s'il est équivalent à un système "sans dynamique", c'est à dire un ensemble de fonctions arbitraires.

This thesis introduces the new concept of flatness. A system is differentially flat (or simply flat) if its behaviour can be completely described by a set of differentially independant functions depending on the system variables and their derivatives: any trajectory of the system can be recovered from the knowledge of this set of functions without integrating differential equations. Flatness is defined through an equivalence relation, called equivalence by endogenous feedback. Two systems S and T are equivalent if there exists a bijective correspondance between trajectories of S and trajectories of T. A flat system is by definition equivalent to a system "without dynamics", that is a set of arbitrary functions.; On introduit dans cette thèse le concept nouveau de platitude. Un système est différentiellement plat (ou plus simplement plat) si son comportement peut être complètement décrit par un ensemble de fonctions différentiellement indépendantes dépendant des variables du système et de leurs dérivées : toute trajectoire du système peut s'obtenir à partir de cet ensemble de fonctions sans intégrer d'équations différentielles. La platitude se définit par l'intermédiaire d'une relation d'équivalence. Deux systèmes S et T sont équivalents s'il existe une correspondance bijective entre les trajectoires de S et celles de T. Par définition, un système est plat s'il est équivalent à un système "sans dynamique", c'est à dire un ensemble de fonctions arbitraires.

Skeptics are made, not born. One is driven to skepticism from some non-skeptical place of origin. One may be carried by different routes, but one must be carried by some route or other. Both one’s starting point and one’s destination lie within the rather vague boundaries of what may be called common sense. The skeptic, despite appearances, does not deny common opinion. On the contrary, he abandons one platitude for the sake of others., He appeals not to arcane considerations, hidden details, but to familiar intuitions. These lead him perhaps to reject something important but, from this point of view, to do so only for the sake of the larger edifice.

Last year a colleague of mine looked after a couple having their first baby. She offered a total package of care and continuity from diagnosis of pregnancy through to discharge to the health visitor. Her client, Sarah, wanted the on-going support of a midwife she knew and trusted. She was ambivalent about being pregnant as it wasn't planned and she was committed to her career. Her first reactions were to say she wanted an elective epidural in labour, not to breastfeed and to return to work as soon as possible. Her feelings of ambivalence were overlain with a predisposition to anxiety and depression, episodes of which she had experienced in the past requiring short doses of medication.

Consider the platitude, ‘all people are basically (i.e. emotionally) the same’. How would we know? Observing people in a culture very different from our own, it would seem that we have to presuppose some such universality, just in order to understand them, but then we beg the very thesis in question. This essay considers one case study of other people's emotions, a study of Eskimos in Jean L. Briggs's Never in Anger. The problems surrounding the method of ‘empathy’ are discussed and an alternative methodology suggested for cross‐cultural observation of emotions which are not subject to these problems.

The widespread debunking of the theoretical canons and political groundings of structural-functionalism, as well as the equally trenchant attacks on dominant sociological research methodologies, have plunged sociologists collectively, and sometimes individually, into a crisisnonetheless real for its having become almost a platitude. This crisis, in some sectors, has verged on paralysis. Other, more dynamic traditions have seized the time to develop

In his paper ‘Knowledge and Reasons’ B. A. O. Williams remarks: “That there should be radically impersonal knowledge seems, on the face of it, impossible: ifpis known, then somebody must surely know it”. Williams points out, however, that this “apparent platitude” has strongly counter-intuitive consequences. let ‘Kp’stand for ‘it is known thatp',and’Kap’for’ a knows thatp'.

At the close of my remarks, I will employ a favorite platitude of speakers. I will write: there is no time like the present. But this platitude has a fascinating philosophical second meaning that's worth one minute of our time. Actually, there is no present. Human existence has a past time and a future time, but the interval in-between, which is presumed to be present time, is theoretically not time at all. The moment behind the present is already time past, and the moment ahead, time future. Thus, the interval between is an existential unit so infmitesimal and so brief as to defy our capability to measure it in the way we measure past and future. This non-time is a leap, a movement, an action between the past and future in which the qualitative difference between the two times can be established. It is this leap between the two static infinities of time that we call the present and that provides the only opportunity for human society to act on the wisdom gained from the past in order to improve the prospects for the future. The failure to use the leap, to act, condemns the future to being no more than a continuum of the past-its unrelieved mistakes and failures to be exacerbated and its unresolved regrets to be compounded. The only way to live this interval of the present-this leap-is to act for the future. Our platitude takes on a new signifIcance. There is no time. There is no present. There is only a leap to make, an act to take -mistakes to correct, failures to undo, regrets to conquer-a future to make better than the past.

The "platitude" principle of semantics (PPS) pronounces that the meaning of the whole is a function of the meaning of its parts. By "whole" it means a whole sentence. By "its parts" it means its words, the expressions made out of these words, and the structure, all of which are the proper con? stituents ofthat whole,1 "the meaning of a sentence". A sentence can have more than one meaning, and so of course can its components. But each meaning is a function from the meanings of each of the components to a meaning of the whole. To most this principle seems a sort of platitude, if not utter triviality. However, it can only be trivial in that it seems obvious, not for lack of interesting implications. My aim in this study is not to challenge the soundness of the PPS but rather to remove the air of obvious? ness it has. If it is true, I shall argue, it is true only after taming and being tamed by counter-examples and alternatives. Following Dana Scott,2 the reasons I shall amass against the PPS are of two related kinds

THE SOCIOLOGY OF KNOWLEDGE is a fairly new and still fluid discipline which, I suspect, will increasingly influence and involve historians who are probing the dynamics of cultural change. Its subject is the relation between thought and life-styles. The general proposition that the way we live tends to be connected with the way we think is a platitude. It can become very puzzling, however, when one tries to find out just how that relationship has operated in a specific historical situation. Despite this potential fascination, historians are still normally suspicious of the sociology of knowledge for two reasons.

The problem of the greatest term of a binomial expansion is a favourite one in elementary text-books, and its solution is often difficult to a beginner. The difficulty, at least in the case where the index is negative or fractional, seems to be caused by the fact that a “formula” is provided which gives a value for r, such that the (r + 1)th term is the greatest. Moreover, this formula is not always the same. Sometimes it is sometimes ; and unless the student has a very good memory he is sure sometimes to make mistakes. Elementary mathematics ought not to be a memory exercise. It is a platitude to say that the educational value of the teaching of mathematics lies in its training of the powers of reasoning. This element is eliminated when processes of reasoning are reduced to a rule of thumb. As well might one use “Molesworth” as a text-book of the principles of mechanics.

Nowadays it is a platitude to say that the approach of HERMANN GUNKEL to the book of Psalms has initiated a new era in the study of the Psalter. Therefore we feel entitled to begin our survey of opinions from the year in which his commentary on Psalms appeared (1926) 1). Summing up the results of an inquiry of literature on this subject, we find that there are, largely speaking, three trends in relation to the structure of Ps. cxxxix

The argument of a recent article is examined regarding the alleged reasons why American sociologists have adopted their present concepts and methods. The assumption that the methods and concepts of social science, unlike those of physical science, must be modified to suit current political upheavals is shown to be historically false. The platitude that "science has been conditioned by history" obscures the fact that science is itself a major part of history and has fundamentally conditioned historical development. Science is a more basic "cultural system" than any of the current politico-economic ideologies.

THAT the freedom of the press is the liberty of the people has been said so often that it has become a platitude. Nobody has questioned it in theory, and now we are seeing the culmination of three centuries of experience, since Milton enunciated the doctrine in the Areopagitica, which demonstrate it in practice. The first liberty the dictator curtails is that of the press. This is true whether the dictatorship is avowed or covert, and whether it is political, economic, social, or religious. He who can determine what the people shall not know can shape them by other devices to his purpose. We live at this moment in a world in

I take the following to be a platitude about knowledge: there would be no problem of knowledge if everything always had been, were, and always would be just as we believe it to be. In one way or another the problem of knowledge is motivated by of our familiarity with the gap between appearance and reality. So it is an intuition that survives our reflections on knowledge that what we might call “an incorrigible world,” any world ω where for all propositions p, if S believes that p at ω, then p at ω, is a world where one knows to be true everything one believes to be true. One might hope that our best account of the nature of knowledge might explain why this platitude is platitudinous. If not, one would at least hope for the preferred account to be compatible with it. Unfortunately, coherence accounts of knowledge do not fulfill this hope, for they imply that there are some incorrigible worlds that are epistemically inaccessible. I will consider the coherence analysis offered in The Structure of Empirical Knowledge, by Laurence Bonjour as a representative case, showing why that analysis is inconsistent with the above platitude, and suggest why this is general problem for coherence theories. I end by suggesting that a solution to the problem is to abandon the presupposition present in many coherence theories that coherence properties are world-invariant.

Here is a big fact: Scientists are good at doing science. It seems a platitude, yet there are those, such as David Bloor, who would deny it.1 On the other hand, most people, including most philosophers, would agree that scientists are good at doing science; nevertheless, these same philosophers don’t seem to think this fact is in any way interesting or important. But it is. There are few facts in philosophy; let’s not let this one slip through our fingers.

It is indeed for me a great honor to be called upon to present the introductory paper at this symposium. I regret that I cannot appear personally. In my view, the purpose of this introduction is not to lecture on new techniques of residue analysis, which will be treated anyway in special papers. Furthermore, it would be tantamount to nothing more than a platitude if I were to point out to this group that the problems and techniques of residue analysis cannot be properly dealt with in thirty minutes. Comprehensive reports have recently been published which give a better presentation of this subject: in English by Gunther (1962), in German by ourselves (Frehse and Niessen 1963), and in French by Lemoan (1962).

S i R t~ R I C A s I~ B Y recently said: "The writer on education rides on the horns of a dilemma; on the one hand he cannot avoid platitudes because there is nothing new to be said; on the other hand he cannot avoid platitudes because the lessons they teach have not yet been learnt, and they still need to be repeated." Such a platitude is the statement: The primary responsibilities of a clinical depar tment are teaching, research, and the provision of medical care of quality worth emulating. Training for academic careers as investigators, clinicians, and teachers will be discussed on the basis of experiences in privately and state supported medical schools, in a community hospital of high aims, in university and governmentally supported hospitals, and in government and faculty committees. Observations were not systematically recorded and, thus, do not meet criteria for validation of narrative data? Furthermore, differing community needs to which medical schools must respond will affect the degree of relevance of the opinions expressed. No

Parmi la diversité des images composites actuelles, cet article se concentrera sur des créations travaillant avec la multiplication de modes de représentation au sein d’une même image (images 2D, 2,5D, 3D ; images appareillées, générée par ordinateurs ; fixes, en mouvement). L’analyse s’attachera à faire émerger le rapport renouvelé aux différentes images sollicitées et à la fonction du compositage dans ces productions., Among the diversity of contemporary composited images, this paper will focus on artworks dealing with multiple modes of representation within the same image (2D, 2,5D, 3D images; images made by cameras, generated by computers; still and moving images). This analysis will therefore explore the renewed relation between humans and the various images used, as well as the different functions of compositing in these artworks

Cet article présente l'application des principes de la platitude aux systèmes linéaires non entiers MIMO à l'aide d'une pseudo représentation d'état. L'objectif est de d\'{e}terminer les sorties linéaires plates pour les systèmes LTI commandables représentés sous la forme de matrices polynômiales. Les matrices de définition, exprimées à l'aide des variables du système, la sortie plate et ses dérivées successives, caractérisent le noyau d'une matrice polynômiale. La platitude en planification de trajectoire est utilisée afin de déterminer les commandes à appliquer, sans avoir à intégrer d'équation différentielle quand la trajectoire est connue. De nombreux développements ont été effectués pour les systèmes LTI, cependant, concernant les systèmes non entiers, et particulièrement en MIMO, les travaux de recherche sont ouverts. L'approche présentée ici consiste à appliquer la platitude, en utilisant les matrices polynômiales, aux systèmes fractionnaires linéaires multivariables.

IT has become a platitude to say that modern science has provided man with unlimited power over Nature; but if Nature includes man, the platitude is false. Slums, unemployment, starvation, and wars bear ample witness to this. We may be able to devise the most cunning calculating machines, we may conquer the sea, the air, and the road at incredible speeds, we may flash messages around the globe, probe the atom, and span the outermost confines of space, we may multiply our productivity a thousand-fold, but we have not yet conquered the simple problem of distributing the produce of the earth among its inhabitants. Has the world population multiplied so enormously that, even with the immensely increased productivity that science has provided, we inhabitants of the globe cannot supply our needs, or are we merely still unscientific fools who-have not yet considered the first step towards a rational view of world supply and distribution? The fact is, of course, that we are still so steeped in historical and racial prejudices that we have not yet a glimmering of the historical and racial prejudices we have to overthrow before we can examine this question with scientific detachment. The Time-Journey of Dr. Barton: an Engineering and Sociological Forecast based on Present Possibilities. Edited By John Hodgson. Pp. viii 4 + 89 + 16 plates. (Egginton, Beds.: John Hodgson, 1929). 3s. 10d.

A MONG a vast array of safe assertions, safest of all are wide generalizations concerning the abiding qualities of a nation or a people. While historical principles which seem universally applicable invite deserved suspicion, yet any rule not too good to be true gathers strength by surviving the exceptions which "prove" it. We should have no fears, for instance, that a lack of contradictory testimony will ever compel us to abandon our ancient belief that the English are a pragmatic race, with an innate propensity for compromise and a congenital aversion to clear thinkingthat they prefer always to muddle through with muddled logic. To this good platitude a host of convenient exceptions clamor for attention, and of these the conduct of Englishmen in the early and middle seventeenth century is surely the most gratifying. Up and down the land were men with utopias in their brains and the voice of God in their ears. What

From the time it was first exhibited about 1900, some thirty years after it was painted, no picture of Degas's has been more universally admired than the Interieur now in the Henry P. McIlhenny Collection (Fig. 1).1 Georges Grappe, the first critic to discuss it, was convinced it was the artist's most important work, “parmi ces chefs-d'œuvre, le chef-d'œuvre,” and alone would assure his fame: “Tous les pastels et toutes les toiles pourraient ětre engloutis par un cataclysme; si elle demeurait, elle imposerait son nom a I'admiration et a l'avenir.”2 Arsene Alexandre, another early critic, went even further to declare it the most important work of any modern artist: “Il n'est pas dans toute la peinture moderne de page plus saisissante, plus austere et d'une plus haute morale, aupres de laquelle les Confessions de J.-J. Rousseau ne sont que platitude declamatoire.”3 For all that, however, it remains the most puzzling of Degas's major works, a picture full of mystery and one still shrouded in mystery as far a...

A so aptly has been said before, "All business is local." This is quoted, not to take sides in the arguments between newspapers and magazines ... not to dust off what, superficially, might be considered a timeworn platitude .. but to emphasize, in the strongest possible manner, the profound importance of the local market. This, in turn, leads to the fundamental necessity of adequately measuring each local market if one is to obtain sound market data.