Sep 03, · , “Des Fondements de la Géométrie: A propos d’un Livre de M. Russell.” Revue de Métaphysique et de Morale, 7: – , “Sur les Principles de Géométrie: réponse à M. Russell.” Revue de Métaphysique et de Morale, 8: 73– , La Science et L’Hypothése, Paris: Flammarion, Translation in b Biographie. Fils aîné de Jacques de Secondat () et de Marie-Françoise de Pesnel (), baronne de La Brède, Montesquieu naît dans une famille de magistrats de bonne noblesse de robe, au château de La Brède (près de Bordeaux, en Gironde), dont il porte d'abord le nom et auquel il reste toujours très blogger.com parents lui choisissent un mendiant pour parrain afin qu'il – Le droit de la famille est une matière qui découle du droit civil, il est donc très important de connaitre les bases apprises lors des cours «d’introduction générale au droit». On étudie une première partie sur le couple et une deuxième sur l’enfant. On a 4 heures d’amphi de droit de la famille par semaines avec 1h30 de
Henri Poincaré (Stanford Encyclopedia of Philosophy)
Henri Poincaré was a mathematician, theoretical physicist and a philosopher of science famous for discoveries in several fields and referred to as the last polymath, one who could make significant contributions in multiple areas of mathematics and the physical sciences. As such, it is strongly influenced by the reflections of Ernst Mach, James Maxwell and Hermann von Helmholtz. However, his thinking is also strongly influenced by the philosophical doctrines of his time those of Emile Boutroux, who was his brother-in-law, but also of Jules Lachelier, William James, etc.
It was not until the s, however, that he became a central actor in the French philosophical scene, notably through his continuous involvement in the Revue de métaphysique et de morale in which he published some twenty articles and his participation in the organization of a large number of events: the celebration of the centenary of the birth of Descartes, the International Congress of Philosophy ofand the international edition of the works of Leibniz.
Poincaré is best known for his critique of logicism and for his geometric conventionalism. In reality, these intuitionistic and formal aspects are two sides of the same coin, given that Poincaré always supports a single position aimed at a reconstruction of the process of understanding scientific theories see Heinzmann Neither formalistic nor intuitionist nor empiricist, dissertation sur le respect de la constitution, Poincare opens a path lying between a realist and an anti-realist theory of mathematical knowledge.
Jules Henri Poincaré was born on April 29, in Nancy in the Lorraine region of France. His father was professor of Hygiene in the School of Medicine at the University of Nancy.
His cousin Raymond was to become the President of the Republic of France during the period — and his younger sister Aline married the philosopher Emile Boutroux. Henri was a precocious student who rose immediately to the top of his class, excelling in both science and letters. During the Franco-Prussian war in the Germans occupied Nancy and the Poincaré family was obliged dissertation sur le respect de la constitution billet the secretary of the civil commissar of Nancy, with whom Henri would have a round of conversation each night after dinner in order to improve his German.
He then took the preparatory classes in mathematics and was first in his class, also first in the academic competition and first in the national competition concours général in elementary mathematics.
In Paris, he entered the École Polytechnique in and after graduating in second in his class having apparently lost points for his inability to drawentered the École des Mines. After brief service as a mine inspector, he submitted a dissertation on partial differential equations and was then hired to teach the course on differential and integral calculus at the University of Caen.
In he submitted a paper solving a problem in the theory of differential equations to the competition for the grand prize in mathematics of the Academy of Sciences in Paris. For the first time he made use of non-Euclidean geometry, which was seen by most of his contemporaries as purely speculative.
In he succeeded G, dissertation sur le respect de la constitution. Lippmann in the chair of mathematical physics and probability. In he was given the chair of mathematical astronomy and celestial mechanics, in he was named professor of theoretical electricity at the Bureau de Poste et Télégraph and in professor of general astronomy at the École Polytechnique.
Poincaré also worked at the French Bureau des Longitudes from Galison Despite a mathematical error that he discovered at the last moment after questions raised by the Swedish mathematician Lars Edvard Phragmén and frantically corrected, the work was important for its use of topology and as a founding document in chaos theory, for Poincaré showed that in general, the stability of such systems cannot be demonstrated.
It is also in this context that he proved his famous recurrence theorem. Poincaré joined the French Academy of Sciences in and became its president in He was elected to the Académie Française in on the basis of his three books on philosophical and general problems in science. He also became a corresponding member of many international scientific organizations. His travel included a trip to America to give a lecture at the St.
He also co-signed a report that played dissertation sur le respect de la constitution important role in the rehabilitation of Dreyfus.
Poincaré is also famous for his conjecture concerning the topology of three-dimensional spheres which remained one of the major unsolved problems in mathematics until the Russian mathematician Grigori Perelman succeeded in demonstrating it nearly one hundred years later.
Poincaré lectured on contemporary mathematical physics for years and was very much abreast of current developments. Popularizer of science, pedagogue, man of letters, he became an icon of the popular press see RolletXLVI. In all he published over five hundred scientific papers and over thirty books. He died July 17, in Paris from a blood clot to the brain which was a complication of surgery, survived by his wife and their four children see RolletBoutrouxGinoux and Gerini Poincaré sets out a hierarchical view of the sciences in Science and Hypothesisalthough he does not explicitly use this terminology.
In dissertation sur le respect de la constitution view the special sciences presuppose physics, which presupposes geometry, which in turn presupposes arithmetic. Poincaré treats topics in a serial order—first arithmetic, then geometry, then physics, etc. The hierarchy interpretation has recently come under criticism in an important pair of articles Dunlop and We believe that clarifying what is meant by hierarchy will resolve this debate.
What is the relationship between arithmetic, geometry and the rest of the sciences? Michael Friedman originated the claim that Poincaré presents the sciences in a hierarchy, and in doing so makes clear that what he means by hierarchy is that each lower level must first be in place in order to be able to proceed to the next level:. Without these presuppositions, however, we certainly would not have been able to discover the law of gravitation. And the same example also shows clearly how each level in the hierarchy of sciences presupposes all of the preceding levels: we would have no laws of motion if we did not presuppose spatial geometry, no geometry if we did not presuppose the theory of mathematical magnitude, and of course no mathematics at all if we did not presuppose arithmetic Friedman Note that Friedman mentions the theory of mathematical magnitude as well.
There is a step between arithmetic and geometry, namely the theory of mathematical magnitude, which is precisely the topic of Chapter 2 of Science and Hypothesis. The theory of mathematical magnitude presupposes the possibility of indefinite repetition, and therefore something like mathematical induction, which Poincaré presents as central to arithmetic in Chapter 1 of Science and Hypothesis.
There is direct evidence that Poincaré thought that mathematics must be in place before we can do any empirical science. Such a claim would be unreasonable. Dunlop, by contrast, seems to have something much stronger in mind with the idea of the hierarchy, which is perhaps why she calls the thesis the dependency hierarchy interpretation.
She seems to take the interpretation to be a thesis of reductionism, that geometry reduces to arithmetic, or at least, the intuitive reasoning used in arithmetic is all that we need in geometry. Commentators have suggested that the intuition that grounds the use of induction in arithmetic also underlies the conception of a continuum, that the consistency of geometrical axioms must be proved through arithmetical induction, and that arithmetical induction licenses the supposition that certain operations form a group Dunlop Rather, he says that we need arithmetic and further things in order to work in geometry.
All that we take Poincaré to be saying is that we still need to add, subtract, multiply, and divide when we are doing geometry, but we will be doing more than what we do in arithmetic. The reason that we need a theory of magnitude before we can do geometry is because we measure things.
The reason we need geometry in classical mechanics is because we are doing things like tracking the elliptical orbits of the planets. We need arithmetic, plus group dissertation sur le respect de la constitution, plus the conventions in order to have metric geometry. Furthermore, the reductionist interpretation cannot be right when we get to the physical sciences, where there is clearly more content in the higher-level sciences—empirical content that could not possibly be reduced to mathematics, dissertation sur le respect de la constitution.
Poincaré discusses the sciences in a sequence, starting with arithmetic. Mathematical induction is essential in arithmetic, because only by using it can we make assertions about all numbers. Poincaré considers mathematical induction to be a genuine synthetic a priori. He next considers magnitude, which requires arithmetic, but goes further. Likewise, geometry extends our knowledge still further, but requires the theory of magnitude to make measurements, and arithmetic to combine numbers.
Poincaré then considers classical mechanics, which again extends our knowledge while relying on the mathematics that came before it.
Finally, he considers theories of physics, where we have genuine empirical results, but based on the mathematics, dissertation sur le respect de la constitution, hypotheses and conventions that came before. Thus the sciences are laid out like expanding concentric circles, with new content being added to the base at each level. The lower levels are necessary preconditions for higher levels, but dissertation sur le respect de la constitution are not sufficient.
Poincaré makes hypotheses central to his analysis of science, distinguishing four kinds, dissertation sur le respect de la constitution, which are actually given in two lists of three each Poincaré 24 and —; 1 and Combining the two lists, these are:.
By verifiable hypotheses, Poincaré means general statements that have been confirmed by experiment. These are the backbone of natural science and can be seen non-controversially to be compatible with standard accounts of, say, the Hypothetical-Deductive method. However, dissertation sur le respect de la constitution, it is important for Poincaré that this is not all of science, as he is arguing for a view of science that is between empiricism and rationalism.
Indifferent hypotheses are ontological in nature and are, for example, mechanical models of underlying mechanism. As Poincaré emphasizes, these can frequently be exchanged without sacrificing empirical accuracy. It is difficult not to suppose that the influence of very distant bodies is altogether negligible, that small motions obey a linear law, that the effect is a continuous function of its cause.
I would say the same of the conditions imposed by symmetry. All these hypotheses form, so to speak, the foundation common to all the theories of mathematical physics. Finally, apparent hypotheses are definitions or conventions rather than actual claims about the world. They therefore may not be considered to be hypotheses at all, although they are, however, often mistaken for hypotheses. Poincaré argues that metric geometry is the hypothesis most prone to such confusion, dissertation sur le respect de la constitution.
Although he presents arithmetic in Science and Hypothesis without mentioning hypotheses explicitly, we can see a role for them in his analysis here as well, which we will present in the order that he follows.
The principle of mathematical induction is necessary to prove general statements about numbers and is thus a necessary tool in mathematics. Therefore the principle of mathematical induction is similar to a natural hypothesis or at least plays a similar role to that of a natural hypothesis. Of course, there are important differences between mathematical induction and the principle of induction used in the natural sciences.
The principle of mathematical induction gives certainty, while the inductive generalizations in the natural sciences give only probability 27; 3.
Poincaré argues that metric geometry is neither a priori nor empirical, but rather conventional. It is important to note, however, that these conventions are guided by experience according to Poincaré, rather than being totally arbitrary, as some later writers take conventions to be.
The existence of consistent alternative geometries shows that the geometry of space cannot be determined a priori. The fact that we experience material bodies and their relations, rather than space, leads Poincaré to argue that the geometry of space cannot be determined empirically either. Thus, statements about the geometry of space are apparent hypotheses or dissertation sur le respect de la constitution that appear to be making descriptive claims, however they are actually closer to definitions, though they cannot be reduced to being merely linguistic.
Poincaré conceives of our perception of objects as a combination of motor and visual impressions that are at first non-spatial. Sensible space is a necessary condition for our understanding of our place in the world, dissertation sur le respect de la constitution, that is, for our understanding of the objects around us, their relations and how they move, but it is not a form of our sensibility, since individual sensations can exist without it Poincaré 3.
Thus sensible space can be seen as an example of a natural hypothesis. We introduce a metric to this space in order to measure distance by using the language of group theory, that is, the mathematical study of abstract algebraic structures. Groups serve as a tool of reasoning about representations of muscular sensations. We can choose a group or sub-group which corresponds to the geometry of Euclid, dissertation sur le respect de la constitution, Lobachevskii or Riemann to describe space.
Poincaré proposes a criterion of choice between the three possible geometries, positing. the existence of an invariant sub-group, of which all the displacements are interchangeable and which is formed of all translations, dissertation sur le respect de la constitution. The empirical underdetermination of the groups has a purely contrastive arbitrary character if the groups are isolated from the background beliefs furnished by our mind Stanford In contrast to geometry, no choices between alternatives are given in arithmetic.
We have thus far discussed arithmetic and geometry and examined a priori principles, natural hypotheses, and apparent hypotheses.
Méthodologie de la dissertation en droit (Exercice + corrigé)
, time: 7:17Cours de philosophie sur le Droit - blogger.com
La doctrine du droit naturel ne peut aboutir qu'à la destruction de l'Etat, car, en proclamant la supériorité de la loi naturelle sur les lois civiles, on fait non seulement un devoir au souverain de se tenir dans les bornes de la justice, on accorde aussi aux citoyens le droit de refuser d'obéir aux ordres qui n'ont pas l'approbation de Biographie. Fils aîné de Jacques de Secondat () et de Marie-Françoise de Pesnel (), baronne de La Brède, Montesquieu naît dans une famille de magistrats de bonne noblesse de robe, au château de La Brède (près de Bordeaux, en Gironde), dont il porte d'abord le nom et auquel il reste toujours très blogger.com parents lui choisissent un mendiant pour parrain afin qu'il Sep 03, · , “Des Fondements de la Géométrie: A propos d’un Livre de M. Russell.” Revue de Métaphysique et de Morale, 7: – , “Sur les Principles de Géométrie: réponse à M. Russell.” Revue de Métaphysique et de Morale, 8: 73– , La Science et L’Hypothése, Paris: Flammarion, Translation in b
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