This name is given to any collection of similar individuals of the same nature which exist, although we can observe only some of these individuals, and never the entire collection of all at the same time.

Cette édition numérique a été réalisée à partir d'un support physique, parfois ancien, conservé au sein du dépôt légal de la Bibliothèque nationale de France, conformément à la loi n° 2012-287 du 1er mars 2012 relative à l'exploitation des Livres indisponibles du XXe siècle. Pages de début Avant-propos Préface : le mythe du précurseur 1. Qui fut Lamarck? 2. La nature 3. La « série » et les « circonstances » 4. « La transmission des acquisitions » 5. Les (...) avatars de la notion d'adaptation 6. Quand l'histoire se lit à rebours Conclusion : Lamarck au passé, au présent, au futur Bibliographie Pages defin. (shrink)

As a historical figure, Lamarck proves a rather difficult subject. His writings give us few explicit leads to his intellectual debts; nor do they present his theories as the outcome of any sustained course of observations or experimental research; and, what is equally frustrating, it is hard to see how his personal development as a scientific theorist was affected by the dramatic political and social upheavals of the period, in which he took an active and lively interest. And so, (...) with his importance for later writers much clearer than his relationship to those of his own and earlier ages, historians have repeatedly interpreted his works as prophetic of doctrines developed more fully by subsequent generations. No less surprisingly, this facile tactic has provoked a reaction; we have been offered Lamarck as a Stoic, a romantic, harking back to Heraclitus. (shrink)

Lamarck's evolutionary theory has been regarded as groundless speculation by both coeval naturalists and modern historians of science. Lamarck is usually regarded as belonging to the group of the " idéologues" – followers of Condillac, with a strong empiricist outlook. Indeed, Lamarck refers respectfully to Condillac, and in his methodological discourse presents himself as an empiricist. However, if one compares his evolutionary theory with the empiricist requirements, Lamarck's work should be dismissed as groundless – a mere (...) metaphysical " système" – in the pejorative sense used by the followers of Condillac. There is, however, another way of looking at Lamarck's method. The analysis of his later works – specially Histoire naturelle des animaux sans vertèbres and Système analytique des connaissances positives de l'homme – shows that he did not follow an empiricist method. His point of departure is indeed metaphysical, but it is exactly the kind of metaphysics now accepted by the biological sciences: a strict physicalism, that requires that all natural phenomena be explained by natural laws. Following this requirement, Lamarck's method seems the best available solution of that time to the fundamental biological problems: the nature, origin and structure of living bodies. Lamarck's work was criticized as purely speculative and non-scientific because it was evaluated in the context of empiricism. He was not altogether clear about his method and maybe he did not realize that he was departing from the empiricist tradition. The reinterpretation of Lamarck's theory from the point of view of his non-empiricist physicalism allows a favorable evaluation of his work. RESUMO: A teoria evolucionista de Lamarck tem sido considerada como uma especulação sem fundamento, tanto por naturalistas de sua época quanto por historiadores atuais da ciência. Lamarck é usualmente considerado como pertencendo ao grupo do "idéologues" – seguidores de Condillac, com uma forte tendência empirista. De fato, Lamarck se refere com respeito a Condillac, e em seu discurso metodológico apresenta a si próprio como empirista. No entanto, se compararmos sua teoria evolucionista com as exigências empiristas, o trabalho de Lamarck deveria ser rejeitado como desprovido de fundamentos – um mero "système" metafísico – no sentido pejorativo utilizado pelos seguidores de Condillac. Há, no entanto, outro modo de considerar o método de Lamarck. A análise de seus últimos trabalhos – especialmente os livros Histoire naturelle des animaux sans vertèbres and Système analytique des connaissances positives de l'homme – mostra que ele não seguia um método empirista. Seu ponto de partida era na realidade metafísico, mas é exatamente o tipo de metafísica que é atualmente aceita pelas ciências biológicas: um fisicalismo estrito, que exige que todos os fenômenos naturais sejam explicados por leis naturais. Seguindo essa exigência, o método de Lamarck parece a melhor solução disponível naquela época para os fenômenos biológicos fundamentais: a natureza, a origem e a estrutura dos seres vivos. O trabalho de Lamarck foi criticado como puramente especulativo e não-científico porque foi avaliado no contexto do empirismo. Ele não foi totalmente claro sobre seu método, e talvez ele próprio não tivesse percebido que estava se afastando da tradição empirista. A reinterpretação da teoria de Lamarck sob o ponto de vista de seu fisicalismo não empirista permite uma avaliação positiva de seu trabalho. (shrink)

D. Boulanger. Colloque Lamarck Paris, Vrin, 1980 EVOLUTION DU GROUPE DES NUMMULITES C'est en 1801 que Lamarck dans son Système des animaux sans vertèbres proposa le genre Nummulites qu'il considéra comme le 89e des ...

Etude consacrée à Lamarck, au lamarckisme et à son importance dans l'histoire de la biologie et des sciences humaines.

Transformations of Lamarckism is an edited volume arising from a workshop to commemorate the bicentenary of the publication of Philosophie Zoologique. The contributed chapters discuss the history of Lamarckism, present new developments in biology that could be considered to vindicate Lamarck, and argue for a revision, if not a revolution, in evolutionary theory. My review argues that twentieth and twenty-first century conceptions of Lamarckism can be considered a reaction to August Weismann’s uncompromising rejection of the inheritance of acquired characters (...) in the late nineteenth century. Weismann rejected the inheritance of acquired characters both as a proximate mechanism of heredity and as an ultimate cause of adaptation. I argue that Weismann’s proximate claim is still valid for the kind of mechanism that he had in mind but that the inheritance of acquired characters has come to refer to many different processes, some of which undoubtedly do occur. However, processes of physiological adaptation and adaptive plasticity, even if transgenerational, do not challenge Weismann’s claim about the ultimate causes of adaptation because these processes can be understood as evolving by natural selection. Finally, I discuss some of the emotional and aesthetic reasons why many find Lamarckism an attractive alternative to hard-core neo-Darwinism. (shrink)

Lamarck's perspective on change within the organic world, in particular his conception of "la marche de la nature," , crystallized during the last decade of the 18th century and the early years of the 19th. I argue that it should be viewed as resulting in part from interactions with, and transfers from, the social thought—modes of thinking, ways of conceptualizing, models, metaphors and analogies—of the decades before the French revolution and of the revolutionary decade itself. Moreover, Lamarck's involvement (...) with the new institutional frameworks initiated during the revolutionary period had brought him into direct contacts with the then prevalent modes of discourse on things social. (shrink)

En este texto, presento a Lamarck, como un autor que debe ser considerado, no solo como uno de fundadores de la biología, sino uno de los precursores del positivismo. Se examinarán nociones de “fuerza vital”, organización, “plan de la naturaleza”, “sentimiento interior” y hábito, pilares de su teoría de la transformación. Esta teoría fusiona el determinismo inherente al “plan de la naturaleza” (PN) con el papel más flexible del “sentimiento interior” (SI) y el hábito en la modificación. Es así (...) como, Lamarck defendió un holismo materialista que justifica la imagen de una naturaleza que, al organizar la materia, da lugar a la generación espontánea de seres vivos simples que a lo largo del tiempo se transforman incrementando los grados de organización, culminando con la aparición del hombre. Idea que Comte extrapoló para justificar un progreso social atado a la aparición de las ciencias positivas. Este trabajo también evalúa la crítica de Comte a Lamarck acerca del papel del medioambiente, cuyo potencial de cambio estaría limitado por “la existencia de “obstáculos interiores” a la modificación, superados en los humanos mediante la emergencia de la sociedad. Ambos autores estuvieron influenciados por François Quesnay, quien propugnaba una sociedad regida por una ética basada en una ley natural biológica. Pero, mientras Lamarck anticipaba el riesgo de la autoextinción humana, Comte consideraba que el verdadero progreso se lograría al convertir esa ley natural en fundamento de una nueva religión secular. (shrink)

This paper analyzes the impact that Lamarckian evolutionary theory had in the scientific community during the period between the advent of Zoological Philosophy and the publication Origin of Species. During these 50 years Lamarck’s model was a well known theory and it was discussed by the scientific community as a hypothesis to explain the changing nature of the fossil record throughout the history of Earth. Lamarck’s transmutation theory established the foundation of an evolutionary model introducing a new way (...) to research in nature. Darwin’s selectionist theory was proposed in 1859 to explain the origin of species within this epistemological process. In this context, Charles Lyell’s Principles of Geology and Auguste Comte’s Cours de Philosophie Positive appear as two major works for the dissemination of Lamarck’s evolutionary ideology after the death of the French naturalist in 1829. (shrink)

Neither can we... improve a science, without improving the language or nomenclature which belongs to it.Ludwig Wittgenstein famously claimed that it was the task of scientists to investigate matters of fact, whereas philosophers merely had to clarify the meaning of terms. One could also—or more precisely—argue that philosophers should identify and remedy five kinds of possible dysfunctions in the relationship between epistemic terms and their referent: they can be meaningless, imprecise, indiscriminate, ambiguous, or inapt. One of the main reasons why (...) “Darwinism” is an inapt term is that it has ideological connotations, like Marxism and similar “ism” words (Greene 1986; Roger... (shrink)

This paper studies Lamarck's scientific method both from the point of view of his methodological discourse and according to his scientific praxis. Lamarck's methodology is compared to Condillac's as well as to that of the idéologues - a group in which Lamarck is usually included. The analysis of this paper shows that Lamarck's methodological discourse is very similar to Condillac's, but his scientific praxis does not follow this view. Instead of following an empiricist approach, Lamarck's (...) work is grounded upon general metaphysical principles concerning nature. Thus, from the ideologues's point of view, Lamarck's work should have been rejected -and that is what really happened - as being a mere metaphysical system grupo no qual se costuma incluir o próprio Lamarck. Mostra-se que o discurso metodológico de Lamarck assemelha-se ao dos ideólogos; no entanto, sua prática científica não se coaduna com esse enfoque. Em vez de seguir uma abordagem empirista, a obra de Lamarck se fundamenta em princípios metafísicos gerais sobre a natureza. Sob o ponto de vista dos ideólogos, seu trabalho deveria ser rejeitado - o que de fato ocorreu - como um mero sistema metafísico - no sentido pejorativo utilizado pelos seguidores de Condillac. No entanto, o presente artigo argumenta que esse é justamente um importante e inovador aspecto da obra de Lamarck, que permitiu a eclosão do evolucionismo moderno. (shrink)

Jean-Baptiste Lamarck was a prolific writer, a multifaceted naturalist, and a zoologist by second profession. Throughout his adult life he lived up to his passion of politely contributing to the advancement of natural philosophy by publishing more than 30,000 pages, probably too much for even the most scrupulous historians of science who seek to reconstruct his theories and to shed some light on the role he played in late eighteenth-century and early nineteenth-century biology.

Nothing in McKay & Dennett's (M&D's) target article deals with the issue of how the adaptivity, or some other aspect, of beliefs might become a biological adaptation; which is to say, how the functions discussed might be coded in such a way in the brain that their development was also coded in gametes or sex transmission cells.

Modern physics was born in the 17th century and modern biology one century later. Immediately, scientifics and philosophers ask themselves what is the relationship between those two sciences and between properties of non-living and living matter. Among those scientifics and philosophers, some think that mental phenomena are of biological nature — they are materialists —, so they encounter a second problem: what is the relationship between properties of non-thinking and thinking living matter? This paper examines the doctrine of three French (...) philosophers of the (post-) Enlightenment on those subjects: Diderot, Cabanis and Lamarck, and, as their answer is in terms of causality and supervenience, I compare succinctly their doctrine with those of Searle and Kim. (shrink)

The world, unfortunately, rarely matches our hopes and consistently refuses to behave in a reasonable manner. The psalmist did not distinguish himself as an acute observer when he wrote: "I have been young, and now am old; yet have I not seen the righteous forsaken, nor his seed begging bread." The tyranny of what seems reasonable often impedes science. Who before Einstein would have believed that the mass and aging of an object could be affected by its velocity near the (...) speed of light? (shrink)

Darwin's theory of evolution brought to an end the static view of nature. It was no longer possible to think of species as immortal, with secure places in nature. Fluctuation of population could no longer be thought of as occurring within definite limits which had been set at the time of creation. Nor was it any longer possible to generalize from the differential reproductive potentials, or from a few cases of mutualism between species, that everything in nature was “fitted to (...) produce general ends, and reciprocal uses.” 134 The appeal to “design” could no longer be substituted for answers to questions concerning animal demography. Instead, the dynamics of a population had to be viewed as the outcome of species' struggle against animate and inanimate factors in the environment. Both the members of a species and the environmental factors tend to vary randomly, and therefore neither evolution nor population dynamics could be fully understood alone. For this reason Darwin's linking of the two subjects was inevitable and not merely an historical accident. Since Darwin had shown that no automatic equilibrium existed, he demonstrated the importance of closer study of the causes of population dynamics and extinction. He also indicated that an understanding of population depends upon the development of a broad knowledge in ecology.Viewed from another direction, Darwin's work ended the early modern era of population studies by clarifying three interrelated problems which were important for understanding population: extinction, distribution, and the nature of species. The components of his answer had been discussed in the eighteenth century, but there had not existed enough evidence for the completion of the revolution in thought which had then begun. At the beginning of the nineteenth century, Playfair found the evidence for extinction conclusive, and, in spite of Lamarck, Curvier convinced the scientific world that there could no longer be any doubt about it. This was a step the importance of which, with his limited knowledge of biogeography and population, Cuvier could not have fully realized. Lamarck attempted, with his evolutionary theory, to circumvent the necessity for admitting extinction, but he overestimated the adaptability of organisms and in doing so he underestimated the importance of competition and the whole field of ecology. On the other hand, he was not willing to let questions such as the origin of species remain taboo to science. The origin of species was a biogeographical as well as a paleontological question. Humboldt correlated environment with the distribution of species and conveyed the impression that plant communities are subject to change. De Candolle, following the lead of Linnaeus and Humboldt, emphasized the ecological aspects of biogeography, not only the importance of habitat and range, clearly showing the ecological effects of competition. The entomologists Kirby and Spence took a faltering step toward understanding the relationship between population and ecological role, but they fell short of any significant new conclusions. Neither they nor Swainson could fully comprehend the new perspective of De Candolle.Lyell was able to bring together the evidence from these three lines of investigation and weave them into an important synthesis that almost accomplished that Darwin later did. Although opposing Lamarck's theory of evolution, Lyell had a dynamic view of ecology. He realized that population dynamics offered an important key to the understanding of biogeography. Since he knew that species become extinct, he investigated closely the factors which could either preserve or extinguish species. While explaining these factors, he described the interrelationships of species in greater detail than had ever been done before. Forbes continued to develop Lyell's ecological concepts, and his first-hand field experience enabled him to describe biotic communities more concretely than Lyell had.Having the advantages of Lyell's understanding and his own experience from a global voyage, Darwin could take the final step from the static to the dynamic concept of life. He had seen populations fluctuating and also fossil species in South America, and on the Galapagos Islands he had encountered a biogeographical problem that could not be credibly solved without the idea of evolution. However, the bare idea of evolution did not fully answer his questions. He sought physiological causes of extinction before he read Malthus and realized that De Candolle and Lyell had correctly emphasized the importance of competition. Darwin found that, in order to understand evolution, he needed to improve his understanding of ecology. He wanted to know when populations were most easily decimated, how extensive were competition and cooperation, what effects parasites have upon populations, and what changes occur in biotic communities when a species is either added or subtracted. He contributed to some extent to answering these questions. Though there remained much for others to do, there was now a new and more secure theoretical framework within which later studies could be interpreted. As Ernst Mayr has observed, Darwin's “consistent thinking in terms of population has had an impact on biological theory and practice which is second only to his sponsorship of natural selection as the mechanism of evolution.” 135. (shrink)

The Romantic- and Revolution-era French naturalist Jean-Baptiste Lamarck is an important precursor for Jablonka’s and Ginsburg’s theory of living beings as beings that learn. Lamarck defined living beings as beings that compose and create. Like Jablonka and Ginsburg’s learning theory, Lamarck’s composing and creating theory locates life in the capacity for a kind of purposeful striving. A consideration of his theory can suggest fundamental questions for Jablonka and Ginsburg regarding the relations among what they call “vivaciousness,” the (...) state of living organisms, learning, and evolutionary transformation. (shrink)

This essay attempts to describe the neo-Lamarckian atmosphere that was dominant in French biology for more than a century. Firstly, we demonstrate that there were not one but at least two French neo-Lamarckian traditions. This implies, therefore, that it is possible to propose a clear definition of a (neo)Lamarckian conception, and by using it, to distinguish these two traditions. We will see that these two conceptions were not dominant at the same time. The first French neo-Lamarckism (1879–1931) was structured by (...) a very mechanic view of natural processes. The main representatives of this first period were scientists such as Alfred Giard (1846–1908), Gaston Bonnier (1853–1922) and Félix Le Dantec (1869–1917). The second Lamarckism – much more vitalist in its inspiration – started to develop under the supervision of people such as Albert Vandel (1894–1980) and Pierre-Paul Grassé (1895–1985). Secondly, this essay suggests that the philosophical inclinations of these neo-Lamarckisms reactivated a very ancient and strong dichotomy of French thought. One part of this dichotomy is a material, physicalist tradition, which started with René Descartes but developed extensively during the 18th and 19th centuries. The other is a spiritual and vitalist reaction to the first one, which also had a very long history, though it is most closely associated with the work of Henri Bergson. Through Claude Bernard, the first neo-Lamarckians tried to construct a mechanical and determinist form of evolutionary theory which was, in effect, a Cartesian theory. The second wave of neo-Lamarckians wanted to reconsider the autonomy and reactivity of life forms, in contrast to purely physical systems. (shrink)

Jean-Baptiste Lamarck is well known as a pre-Darwinian proponent of evolution. But much of what has been written on Lamarck, on his ‘Lamarckian’ belief in the inheritance of acquired characters, and on his conception of the role of the will in biological development mischaracterizes his views. Indeed, surprisingly little in-depth analysis has been published regarding his views on human physiology and development. Further, although since Robert M. Young’s signal 1969 essay on Malthus and the evolutionists, Darwin scholars have (...) sought to place Darwin’s work in its social and political context, this has yet to be done adequately for Lamarck. Here I address this gap. I argue that the will was of particular importance to Lamarck’s social commentary and his hopes for the transformation of the French people and nation. Further, I argue that if we are to really grasp Lamarck’s ideas and intentions we need to contextualize his works in relation to prevailing debates in France about the physiology of mind and morals and the future of the nation. (shrink)