Читать книгу Embryogeny and Phylogeny of the Human Posture 2 - Anne Dambricourt Malasse - Страница 22

Teilhard was in regular contact with Henri Breuil, himself trained by Albert Gaudry, and thus steeped in Lamarckian doctrine. Teilhard understood that the cosmos, which he contemplated from the volcanoes of Auvergne, was in reality the state of a disappeared cosmogenesis, just like the history of the Earth and the complexification of the life at the origin of the biosphere. The fruitful union between environment and organism did not shock him. On the contrary, for a mind that felt consubstantial with nature, like Leibniz and Goethe, it was conceivable to believe in a kind of cosmic super-organism. But the universe was no longer a being as in Haeckel’s monism, and at the present moment, the universe is the stage for multiform growth. Terrestrial organisms are thus compositions built by the physico-chemical laws of their environment, and the essence of consciousness relates to these specific laws which allow the organization of complex autonomous systems. The human being, as a collective reflexive consciousness, was seen as a reflection of this growing being on the Earth, potentially able to become conscious of themselves. But the stage of growth of this cosmic consciousness reached a critical state, as the “planetarization” of conflicts testified. Theological heresy was thus consumed, the truth was no longer in the old texts written by human hands for more than 2,000 years. The authenticity of a cosmic purpose remained the only question which justified, in his eyes, all the sacrifices at the planetary scale; Teilhard set out to discover it, for the first time since the philosophers of the Antiquity, who had not conceived of the necessity to prove it.

Marcellin Boule wanted Teilhard to meet the holder of the chair of Mineralogy at the Catholic Institute of Paris, where higher education in the sciences was still poorly developed. It was important that natural sciences and evolution be taught in private establishments run by the clergy. Father Gaudefroy offered him the chair of Geology, pending the nomination of a professor; Teilhard accepted and became a lecturer. He taught geology there from 1920, defended his thesis at the Sorbonne in 1922, and was finally appointed Assistant Professor of Geology and Paleontology at the Institut Catholique de Paris. Teilhard de Chardin was therefore a professor and continued his teaching during the 1922/1923 academic year, while in agreement with the Society of Jesus, he devoted himself to paleontology in the basement of the Muséum’s gallery and participated in international conferences.

His teaching was innovative, he was not content to simply teach what he had just learned at the Sorbonne. He thought about the mechanisms of evolution on the large scales of space and time, the “continentalization”, or “granitization” (silicification) of the Earth’s crust, and the complexification of organisms which form the biosphere, as far as Man, who discovers himself a generic link with the physico-chemical transformations of the planetary surface. Here, we find Buffon again, but with the search for a physico-chemical, even telluric link (electric and magnetic fields) between the dynamic organization of molecules to form monocellular and then pluricellular autonomous units. The Earth’s crust moves thanks to tectonics (only vertical, for the geologists at this time) and was dragged into the irreversible “drift” of its cooling toward a state of equilibrium, while climates changed and fauna migrated, but with an additional constraint: the surface of the Earth is finite, closed in on itself and the shape of the continents is, in itself, a factor of selective pressure on populations. Peninsulas are dead-ends, isolation routes, while intercontinental bridges are routes of diversity. Teilhard’s evolutionary school of thought was being built: according to him, there is a planetary engine with which the increasing complexity of organisms was associated, from the tectonics of the continents and seabed to the dispersion of the oceans.

This intelligibility of an earthly planetology approached as a growing living organism is already perceptible from the earliest years of his teaching. In 1921, Teilhard published the beginnings of his evolutionary thought in an article for the Études², “How is the question of Transformism posed today?”:

Not only the fact, but the very mechanism of evolution seemed clear: to explain the metamorphoses of life, it was enough to have recourse to adaptation or natural selection, and to heredity, already a little schematized, the figure of Transformism from Lamarck to Haeckel [...]. The lines formerly drawn disintegrated, so that new explorations brought to light a plethora, in the geological layers, the remains of absolutely new animals, which forced the multiplication of families and zoological orders. Leaves began to hide the twigs, and the twigs, which were too numerous, increasingly hid the branches. For that reason, life became more and more overwhelming for the classifiers, by the richness of its forms. It soon had to be admitted that it was terribly capricious, and inordinately old in its developments. It was first necessary to give up the idea of a regular, continuous, total evolution [...]. The horseshoe crabs of the Pacific are irremediably fixed beings, which did not deviate, in a single important feature, from the type they had in the Secondary, Carboniferous or even Cambrian. This is curious. Even more disturbing, the immobilized types were not species stuck in a kind of morphological impasse. The Malaysian Tarsier or the Lemurs of Madagascar (their morphotype) could have played the role of morphological intermediaries (between the most primitive mammals and the monkeys). We now know true monkeys in the Oligocene, everything is older than we thought, in the world of life. And everything is much more stable too... [...] On groups of ungulates and carnivores, we see it beyond doubt, there are precise, simple, constant rules that preside over the gradual and “directed” complication of organisms, the precious notion of oriented variation [...]. From the smallest detail to the largest sets, our living universe – like our material universe – has a structure, and this structure can only be due to a phenomenon of growth. This is the great proof of transformism, and the measure of what this theory has definitively acquired [...]. From many points of view, a radiolarian, a trilobite, a dinosaur are as differentiated, as complicated as a primate. On the other hand, their nervous system is much less perfect. Should not we look in this direction for the secret law of development? Should we not say that the main stem of the zoological tree has constantly moved in the direction of the largest brain? [...] What makes transformism is not to be a Darwinist or Lamarckist, a mechanic or vitalist, what today’s naturalists hold dear is the fact of a physical connection between the living. (Teilhard de Chardin, Comment se poser aujourd’hui la question du Transformisme, 1921b, author’s translation)

Teilhard had always thought like a geophysicist: for him the appearance of life was a planetary, and therefore a cosmic phenomenon of geophysical origin. For him, as for Buffon (within the limits of the diversity of his “internal mold”), the history of the Earth’s crust had thus shaped biological evolution, tectonics gave an account of the evolution of species on a planetary scale and he saw the spherical enclosure of the Earth as a constraining physical condition:

The continents are natural units of the Earth’s crust, so that the problems of the Biosphere can be studied there [...] paying attention to the organo-plastic action exerted on animal and plant forms by the Continental Environment (inorganic or living) in which they develop. (ibid., author’s translation)

The paleontologist was so convinced that he pushed for the creation of a laboratory of “Continental geology applied to the origins of Man” at the École Pratique des Hautes Études in 1938, housed at the Institut de Paléontologie Humaine (IPH) in Paris. He then created the term “geobiology” for the small Institute that he set up in 1942 in annexes of the French Embassy in Beijing.

For Teilhard, paleoanthropology was a discipline of terrestrial planetology, because the emergence of life and its complexification, whatever its rhythms, was a process of growth on an astrophysical scale which started with particles (quanta), then with atoms and, finally, molecules. Current and fossil species were thus the result of organizational plans which increased in complexity and which would not have been viable without the complexification of the nervous system to control their internal balance and their relationship with their environment. The last organizational plan with complexification of the nervous system is that of mammals. The lineage from the first primates to Homo sapiens was the extension of this growth channeled through the whole of the central nervous system. But Teilhard retained only the endocranial casts described by his contemporaries and did not take into consideration bipedal locomotion, because the skeleton was arbitrary, divided into cranial and postcranial territories. The bones were not seen as forming a system structured around the axial endoskeleton that protected the central nervous system carried by the appendicular skeleton. We thus understand better why the “sphenoid-cervical hinge” is unthinkable in paleoanthropology and how much the straightening of the dorsal cord constituted a huge gap in the map of the hominization process.

Thus, since Aristotle, the place of Man taken as the objective reference of a ruler has never been invalidated. The discovery of evolution has not contradicted this obvious statement, but it was not theologians who rejoiced in it, quite the contrary. The sovereignty of the naturalist had made it possible to link the gradations of the current horizontal rule, by showing that each one of them was the instant of a duration which sunk all the more deeply into the terrestrial strata the more it approached zero, or, here, the origins of life. No paleontologist has been opposed to this observation of increasing neural complexity since the first Chordates (which include Vertebrates).