Nature
The Concept of Nature: The Evolution of Philosophical and Scientific Understandings of the Natural World
The term "nature" evokes a wealth of associations in anyone, even if it may seem somewhat grandiloquent in everyday usage. An average inhabitant of a particular locality connects this word with their immediate or proximate environment. For city dwellers, nature often intrudes upon their comfortable lives through the weather, bothersome precipitation, fluctuations in temperature, houseplants, pets, and excursions "into nature" on weekends. In contrast, most rural residents perceive nature through the lens of their daily labor relations with natural factors. In highly developed countries, there is a noticeable decline in the population that confronts nature face-to-face; this small number comprises primarily farmers and workers in extractive industries. Technological progress contributes to humanity's distancing from nature, and it may come to pass that, in the future, the majority of the Earth's population will relegate their experiences of interactions with nature to the periphery of their consciousness and emotional complexes. Only the media may occasionally bring us alarming images of natural calamities, and astronomers will remind us once more of the potential collisions between Earth and celestial bodies.
Nonetheless, in the spiritual experience of humanity, nature has been imprinted so deeply and in such a form that archaic stereotypes of perceiving nature will continue to manifest for a long time, and perhaps they may never disappear. In historical times, philosophy was one of the first domains to grapple with the relationship to nature. However, long before philosophy, mythological and religious worldviews already reflected various stages of human interaction with the environment. This is a consideration that philosophical thought cannot overlook, as, on the one hand, both myth and religion remain active components of human consciousness, while, on the other, it is only philosophy that possesses the primal reflexive capacity—the ability to investigate all forms of consciousness and knowledge, including philosophical understanding. Therefore, let us first turn to that spiritual legacy concerning how people perceive their relationship to nature.
In the earliest worldviews of all peoples, myths about nature hold significant importance. The most ancient of these were myths about animals and the origins of the sun, moon, and stars. Subsequently, in more developed mythological systems, cosmogenic (the origins of the universe) and anthropogenic (the origins of humanity) myths are prominently represented. It is characteristic that primitive humans projected their properties, qualities, and emotions onto natural phenomena, perceiving in nature the actions of living forces, whether of a zoomorphic or anthropomorphic nature. A hallmark of myth is the obligatory narrative concerning the origins of objects: to describe and explain the external world is to recount its origin, thus providing a sense of satisfaction. Almost universally, the concept of the world has been embodied in the image of the "World Tree." This image is recorded in texts of various genres, in visual arts (painting, ornamentation, embroidery), and in architecture. Vertically, the tree symbolizes three primary cosmic zones: the celestial realm, the terrestrial realm, and the underworld; temporally, the three parts of the tree can symbolize the past, present, and future; in terms of elements—fire, water, earth. Each part of the tree could be associated with specific classes of beings (animals): birds belonged to the upper part, ungulates to the middle, and snakes, mice, frogs, and fish to the lower. In the schema of the World Tree, the horizontal axes might correspond to the four corners of the world, the seasons, times of day, elements of the world, and human actions. As researchers have noted, to a certain extent, the "World Tree" becomes a model of culture as a whole.
From the very beginning, myths were multifunctional and possessed a sacred (from Latin: sacer - holy, magical) character, meaning they were intertwined with religious beliefs. All elements of nature not only appeared alive and animated but were also treated ritually. As Mircea Eliade notes, in "primitive" or archaic consciousness, objects of the external world—much like human actions themselves—do not possess independent, intrinsic value. An object is conceived as if it is a vessel of foreign power that distinguishes it from its surroundings, granting it meaning and value. Metropolitan Hilarion (Ivan Ogienko) cites numerous examples of mythological remnants of pre-Christian origin in the beliefs of the Ukrainian people, particularly regarding water, earth, trees, and specific animals and plants.
Ideas about the origins and structure of nature are also found in all world religions (Buddhism, Christianity, Islam). The initiation of nature in the Christian Bible appears as follows: "In the beginning, God created the Heaven and the earth. And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters. And God said, 'Let there be light!' and there was light. And God saw the light, that it was good; and God divided the light from the darkness. And God called the light 'Day,' and the darkness He called 'Night.' And the evening and the morning were the first day." (Genesis 1). Throughout the lengthy period (approximately one thousand years) of the European Middle Ages, Christian conceptions of the natural world predominated, interwoven with ancient mythological traditions. The medieval perception of the world is characterized by its profound symbolism and hierarchical structure. This symbolism arose from the doubling of the world: alongside the world of natural objects exists the world of corresponding generic concepts, which, although otherworldly, is as real (if not more so) as the former. The world of our everyday experience occupies a subordinate position to the otherworldly, supersensory realm. Every element of earthly existence is a symbol corresponding to an element of the supernatural realm, thereby symbolizing the overarching Divine unity. In the contrast between the visible and the invisible lies the opposition between external appearance and essence, the apparent and the actual, the approximate image of truth and truth itself. The corporeal world has a lesser degree of reality and autonomy than the spiritual world of primordial essences. Symbolism is linked with hierarchical structure, so that, depending on the "degree" of symbolism, different levels of hierarchy can be distinguished: higher symbols, while reproducing "invisible things," simultaneously represent "visible things" that are inferior to them in perfection. Humanity encompasses all of nature within itself; animals do not embody all of nature but possess certain qualities, while plants embody even less. Earth and water serve plants, plants serve animals, and all serve humanity. All relationships in nature are arranged according to degrees of nobility: water is more noble than earth, air is more noble than water, and so forth, in accordance with their proximity to God. Thus, the Universe is constructed!
The medieval worldview should be perceived not only in a strictly Christian aspect but also in the interplay with pre-Christian remnants and the actual capabilities of people to confront natural forces. The Christian world of that time presented a limited collection of individual fortifications of civilization amid the surrounding wild nature with its impenetrable forests and unexploited desolate wastelands. The forest, alien and hostile to humanity, is termed "pustsha" (derived from "empty"), denoting a space devoid of people. The word "field" in ancient Rus' initially meant "empty," a desolate boundary space. Even "selo," which we today associate with settlement, once meant the same as field and was only used from the 12th century to denote the sown portion of the field or the harvest, and later came to include the buildings around the cultivated land. As the French historian Jacques Le Goff notes, in the typical medieval European consciousness, the world is perceived as enclosed in space, surrounded by alien, hostile nature and hostile tribes of pagans or infidels. However, the enclosed, limited earthly world of "proper" people unfurls infinitely upward toward the heavens. Between the earthly and the heavenly realms, there are no barriers, and the soul is capable of finding its way to its native element all the way to God.
Thus, one of the first and most significant parts of the world to which humanity defined its relationship was nature. Philosophy, reflecting the worldview demands, has from the outset also directed its attention to nature. The category of being has helped us preliminarily realize such a simple truth: before a person can comprehend their relationship to the world through thought, they must have the world at hand, that is, the existent. We have sought to understand all possible nuances of "being." Among the forms of being, which do not depend on our consciousness and exist or may exist independently of human intervention, is nature itself.
In philosophy, the concept of nature is employed in several senses. Broadly speaking, nature is synonymous with matter. The distinction between these terms lies solely in emphasis: when we speak of "nature," we refer to the entirety and diversity of material objects, processes, and properties as they exist. Conversely, when we use the term "matter," we aim to highlight (still rather abstractly) only objectivity as the essential aspect of existence. In this broad sense, nature encompasses society as well. While this interpretation may not be particularly productive, it is worth noting, for both "matter" and "nature" are finite concepts of specific sciences.
In a narrower sense, "nature" refers to the immediate objective environment in which human history unfolds, that which humanity encounters constantly. This latter interpretation is the most commonly used; however, there exists yet another additional sense of "nature." This arises when we wish to emphasize the essence of something. Thus, we speak of "human nature," "the nature of beauty," and so forth. But this is a secondary, derivative meaning.
All the aforementioned senses have a long history. The ancient Greeks employed the rather universal term "φύσις," while the Romans used "natura." The term "natura" derives from nascendo (to be born, to emerge, to grow). The primary meaning of "φύσις" also pertains to growth and that which has emerged during growth. However, Martin Heidegger asserted that "φύσις" was understood by the Greeks more as "the self-emerging dominance of being as a whole," and philosophy is the comprehension of the dominance of being that has come into existence by itself. They distinguished this self-emerging being from that which arises from "τέχνή," or human activity. From this, it is already evident that philosophers from ancient times were able to conceive of nature as that which stands in opposition to humanity and as a formidable force that must first be grasped, even if only through thought.
The development of science and philosophy has deepened and greatly diversified humanity’s understanding of the surrounding world. For instance, Aristotle, adopting the Pythagorean view of the Earth as a sphere, added a crystalline dome of stars around it. He positioned the Earth at the center of the universe. Five hundred years later, Ptolemy (90-160) created a model in which the Earth is an unmoving center of the universe, around which the Sun and planets revolve. In the 16th century, Nicolaus Copernicus (1473-1543) altered this view to a heliocentric model, while Giordano Bruno (1548-1600) later introduced the idea of the infinity of nature and countless worlds. Galileo Galilei (1564-1642) substantiated the notion of similarity between celestial and terrestrial bodies, and Isaac Newton (1643-1727) formulated the law of universal gravitation. The completeness and perfection of mechanics inspired Immanuel Kant to develop a hypothesis regarding the origin of the solar system from a primordial nebula through gravitational processes, enabling him to declare in one of his works: "Give me matter, and I will build the universe from it!"
Today, our understanding of nature as the universe has achieved great success. In natural science, the universe (or Metagalaxy) refers to the largest natural sphere available for our observation and research. It is known that the Earth (with an average diameter of approximately 12,700 km) is a planet of the solar system (which spans a diameter of 10 billion km). The Sun is part of our Galaxy (from the Greek γάλακτίκος—milky), which is itself part of the Metagalaxy. The so-called Milky Way, which everyone observes in the starry night sky, is our Galaxy. It consists of about 150 billion stars (luminous plasma spheres), galactic nebulae (gases and dust particles), cosmic rays (a stream of stable, high-energy particles), magnetic fields, and radiation (photons). The Galaxy resembles a disk, with a diameter approaching 100,000 light-years and a thickness of up to 1,500 light-years. It is important to remember that a light-year is the distance light travels in one year at a speed of 300,000 km per second. The distance from the Sun to the center of the Galaxy is about 30,000 light-years, placing it on the periphery of the Galaxy, near its equatorial plane. Since the Sun, along with its planets, has existed for about 5 billion years, it has made approximately 25 rotations around the axis of the Galaxy during its evolutionary time. The speed of the Sun's motion along its circular galactic orbit reaches 250 km per second, completing a full orbit in 200 million years.
Science has concluded that the universe in question has both a beginning and an end. In 1965, cosmic microwave background radiation was discovered (as a constant background in any point of the universe). About 15 billion years ago, all the matter and energy constituting the universe were concentrated in a dimensionless point. Following this, an explosion occurred (the "big bang," as termed by Fred Hoyle). The evolution of the universe commenced, progressing at varying rates during different phases. The first phase is known as the inflationary universe, which is characterized by expansion. This is the period between 10^-43 to 10^-35 seconds after the moment of the "Big Bang." During this time, the universe was in a vacuum-like state, and evolution proceeded extraordinarily rapidly. It is believed that in that first moment, it was multidimensional in a spatiotemporal sense (10^-11 dimensions) and then became three-dimensional. This transformation occurred through the expansion of the universe in three conventional dimensions and contraction in others. Today, the radius of the universe is approximately 10^37 cm. The process of galaxies moving apart from the initial explosion continues to this day.
The Sun follows the laws governing the development of ordinary stars. In about 10 billion years, it will transform into a red giant, expanding to engulf the orbits of all planets, and later will become a white dwarf, and subsequently, a neutron star with a density that exceeds that of atomic nuclei. The planet Earth, with an age of 4.5 billion years, formed through gravitational condensation from a primordial dust nebula. The surface of the Earth covers 500 million km², with more than two-thirds of its surface occupied by the World Ocean. The primary mass and volume of the Earth consist of a metallic barysphere, which is in turn surrounded by a lithosphere, followed by a hydrosphere, atmosphere (composed of 70% nitrogen and 21% oxygen), and biosphere (the sphere of life). Life is perhaps the most crucial feature of our planet. Over hundreds of millions of years, forms of life on Earth have diversified immensely. Today, there are approximately 1.5 million species of animals, with insects being the most numerous (750,000 species), and vertebrates comprising 48,000 species, among which there are 6,000 species of mammals.
Modern physics has also enriched our understanding of the "microcosm," the invisible world of the internal structure of matter. Currently, there are about 350 so-called elementary particles that make up this world. They are divided into the following classes: photons—quanta of electromagnetic fields, particles with zero rest mass; leptons (from the Greek leptos—light), which include electrons and neutrinos; mesons—unstable micro-particles; baryons (from the Greek barys—heavy), which include nucleons (i.e., protons and neutrons), hyperons, and resonance particles that have extremely short lifespans. In characterizing elementary particles, a crucial aspect involves their interactions. Four types of interactions are distinguished based on their range: strong, electromagnetic, weak, and gravitational (with the latter having an unlimited range). Starting from the level of atoms, we know 107 elements, all of which are artificially produced through nuclear reactions.
When discussing living organisms, it is important to note that all are composed of cells, whose sizes range from 1 micrometer to 1 meter. There are unicellular organisms, such as bacteria, while the human organism consists of 500 trillion cells. Cells possess a thin membrane, cytoplasm, and a nucleus that governs protein synthesis. Proteins are the fundamental components of all plants and animals. Proteins are composed of amino acids. Plants and most microorganisms can synthesize amino acids themselves, while animals and humans consume some of them (20 out of 150) through food. These amino acids are termed essential. For human vitality, nine essential amino acids are particularly important. Living organisms also require enzymes (catalysts for chemical reactions) and vitamins, which are necessary for metabolism.
The achievements of science regarding the arrangement of the Universe, the structure of the macro- and microcosm, undoubtedly do not exhaust the current content of the concept of nature. Hegel, in his time, rightly remarked that physics has no rightful claim to interpret the essence of the concept of nature, for it did not create it. The very history of the word "nature" attests to this (in most European languages, the Latin variant "natura" has taken hold). Although in Ukrainian and Russian this word likely has a later origin, it carries the same primordial semantic weight as its Greek or Latin counterparts: the growth through birth, emergence, and may be considered a later calque from "natura" and "φύσις." Examining the history of the word "nature," R. O. Budagov notes that it only became central to philosophical discussions from the 18th century, and by the end of that same century (1798), the explanatory academic dictionary of the French language defined "nature" as the totality of things and beings, the physical world in its most diverse manifestations. In the works of domestic authors, the lexeme "nature" is employed from the 17th century onward, and Theophan Prokopovich, in his work "Natural Philosophy, or Physics" from 1708, already offers at least five meanings of "nature": 1) nature in the sense of God; 2) the essence of any thing; 3) nature as the universality of things; 4) as a natural cause; 5) the term "nature" is used to denote the birth of the living. Clearly, T. Prokopovich was familiar with almost all the meanings of "nature" that have evolved over many centuries of human knowledge. This illustrates a caution against equating the content of the concept of "nature" solely with the achievements of the natural sciences. This concept arose long before physics established itself as a science, and thus not only strictly physical knowledge enriches human understanding of nature. Nature enters our consciousness from early childhood, perceived by us sensibly and rationally, emotionally elevated when we admire a landscape, or with trepidation when we observe fearsome natural phenomena. Depending on the level of existing culture or upbringing, the word "nature" resonates first with either the song of birds and the rustle of leaves or the thought of the utilitarian exploitation of its creations. Therefore, the concept of nature encompasses not only the results of scientific knowledge but also a condensed result of all our perceptions acquired through artistic-aesthetic, everyday, and utilitarian-practical relationships with the surrounding world.
Nature astounds us with the ceaseless variability of its components. The location of things changes, along with their properties, chemical composition, temperature, volume, shape, color, illumination, and so forth. The relative positioning of the elements of nature and their variability are linked to space and time. Humanity has created a vast lexical reservoir to fix the coordinates of things and events in space and time: "here" and "there," "far" and "near," "somewhere" and "nearby," "then," "once" and "now," "yesterday," "today," and "tomorrow," "moment," "last year," and so forth. There are countless such words and corresponding expressions. Space and time are an indispensable central theme of worldview considerations, from primitive myths to developed philosophical and scientific systems. On one hand, nothing is more widespread and familiar in our practical lives than temporal-spatial concerns (for we are always short of time, always "here" or "there," as we yearn to go "there" from "here"), while on the other hand, nothing is more complex to comprehend than the essence of space and time. For instance, regarding one of our acquaintances, Augustine Aurelius wrote about time: "What, then, is time? When no one asks me about it, I know what time is; if I wanted to explain it to someone who asks, I cannot. However, I insist that I know for sure: if nothing passes, there would be no past time; if nothing comes, there would be no future time; if nothing exists, there would be no present time. But how can these two times, past and future, exist when the past no longer exists and the future has not yet come? And if the present always remained present and did not recede into the past, it would no longer be time, but eternity; the present becomes time only because it recedes into the past. How can we say that it exists if the reason for its emergence lies in the fact that it will not be? Are we mistaken in saying that time exists only because it strives to vanish?" It is hard not to agree with such troubled lamentations! Each individual, especially in their youth, grapples with equally troubling questions: is there a beginning and an end to space and time? Why does time flow at different paces in childhood and adulthood? Why does space have three dimensions while time is one-dimensional? Is time travel to the past or future possible? It is striking that similar questions have propelled reflections from those far removed from naivety, both scientists and fantasists alike.
In the culture of various epochs, the perception of space and time is wholly inscribed within the general conditions of life. Myth was not viewed merely as a narrative of the past but as an event that is perpetually repeated and recreated. A medieval person was more inclined toward eternity; their existence in the world was not severed from eternity, and both ends of their life (birth and death) touched eternity, inscribed within it; past, present, and future formed a continuous line of existence. The modern individual rather senses the transience of time, living more in the present; traditions barely connect them to the past, and the everyday hustle and haste obscure their vision of even the near future. The enchantment, to the point of stupor, with the ticking of the clock hands could serve as a portrait of our contemporary individual. Yet, in this, they are both the product and the victim of socio-cultural and historical conditions.
To navigate the problem of space and time, it is prudent to distinguish the layers of their presentation to humanity. The first layer is perceptual space and time (from Latin, perceptio - perception). This pertains to the testimony of personal psychological experience, where all our perceptions appear orderly in spatial and temporal relations, which, however, does not yet give us grounds to unreservedly assert the complete correspondence of our perceptions to the true reality of space and time. Kant categorized space and time as a priori forms of sensibility, as the internal capacity of the human faculties (so to speak, the brain) to organize sensory material in such a way that things seem to be arranged in space and lined up in time. If one refrains from hastily condemning Kant for subjectivism and concedes his point regarding the purely human way of perceiving the structure of the world of "things in themselves," this capacity can be explained through the long process of adaptation of our ancestors to those very "things in themselves." The renowned Austrian zoologist and Nobel laureate Konrad Lorenz (1903-1989) upheld precisely this viewpoint. "In my opinion," he wrote, "the genuine connection between the thing-in-itself and the specific a priori form of its givenness is determined by the fact that this a priori form evolved as an adaptation to the laws of the thing-in-itself in the course of close interaction with these continuously operating laws over hundreds of thousands of years of human evolutionary history. Such adaptation has provided our thinking with a structure that significantly corresponds to the realities of the external world." A normally functioning psycho-physiological apparatus for perceiving the external world enables individuals not only to orient themselves effectively in the world but also to interact productively based on a similarly adequate perception of the environment. Although this does not exclude certain individual discrepancies in the perception of the spatial-temporal properties of natural things.
The second aspect of the presentation concerns physical space and time, which can also be termed conceptual or simply scientific. Space represents a mode of coexistence among objects, where they are coordinated side by side, positioned next to one another. Time signifies a method of change in the states of objects, where this change occurs sequentially, one after the other. These general definitions indicate a certain certainty in the order of the arrangement and transformation of phenomena and objects. One of the most fundamental properties of space and time is their dimensionality. Space is characterized by three dimensions. These three dimensions are both necessary and sufficient to facilitate all processes, forms of motion, and interactions of objects with which science today engages on a macroscopic level. Occasionally, in mathematics, one speaks of multidimensional space. In this context, multidimensionality refers to a mathematical abstraction through which certain aspects and states of physical objects are represented. Here, the concept of "space" is imbued with a specific meaning. Time is one-dimensional, meaning that the position of an event in time can be described by a single parameter. Among the common properties of time are its irreversibility and unidirectionality, manifested in the fact that time can only progress from the past to the future, never the other way around. This latter property arises from the inherent irreversibility of all real processes, particularly the irreversibility of causal relationships. Such asymmetry in these relationships is, in turn, defined by laws of conservation and the laws governing the development of specific objects. Before any phenomenon arises, all the causes that give rise to it must come to fruition.
The development of physical knowledge concerning time and space encompasses two particularly significant stages: the emergence of classical mechanical theory (I. Newton) and the establishment of the theory of relativity (A. Einstein). Newton posited the absoluteness of space and time in the sense that they are an independent reality, unaffected by the presence or absence of any physical masses or processes: space is a uniform void at all points, while time is a pure and uniform duration at all moments. Albert Einstein (1879-1955) rejected the notion of absolute space and time, demonstrating that their metric is relative, inextricably linked to gravitational masses and physical processes, and that there is no absolute, privileged reference point in nature. The magnitude of time intervals between two events depends on the chosen reference frame from which these magnitudes are measured. The relativity of simultaneity implies the relativity of spatial measurement, as the length of a rod, for instance, is nothing other than the distance between the simultaneous positions of its endpoints. The general theory of relativity revealed a connection between the structure of "space-time" and the distribution of gravitational masses. The metric properties of space and time depend on the distribution of gravitational masses. Overall, the advancement of physical theories enhances our understanding of the properties of space and time in the micro-, macro-, and mega-worlds; however, at each specific stage, they correspond with varying degrees of approximation to actual spatial and temporal realities.
The third aspect, which we may tentatively label metaphorical space and time, pertains to the predominantly metaphorical use of "space" and "time," where these terms are not always employed in their direct physical sense but in a figurative manner to enhance imagery. Thus, when discussing social space or its parameters (distance, span), one refers to disparities in social ranks, income, educational levels, and so forth. When the concept of social time is invoked, it encompasses various functions of time within a sociocultural context. The very conditions of social life necessitate the synchronization of human activity, the coordination of their endeavors, the sequencing of actions and processes, the timeliness of duties performed, the measurement of expenditures, and the differentiation of types of activities (work, leisure, vacation, holiday, etc.). There is nothing derogatory about terminological borrowings from physics or other sciences for the realm of humanitarian knowledge; all sciences enrich expressive means through mutual borrowing. Terms like "legal space," "economic space," "cultural space," and many others have long become commonplace. The spatiotemporal terminology is widely utilized, albeit not entirely metaphorically, in legal science and legislation to precisely define legal consequences based on the place and time of actions. For instance, a serious discussion about "time in law," which leads to cultural standards of time perception, is prompted by concepts like "statute of limitations," articulated through legal notions such as:
- Statute of limitations for civil claims—a period for defending a violated right in court: the general period for individuals is three years, while for organizations, it is one year; a shortened period lasts six months.
- The limitation period for executing a criminal sentence—the timeframe after which a sentence cannot be executed if it has not already been carried out (it can range from three to ten years).
- The limitation period for criminal liability—a timeframe after which an individual cannot be held criminally responsible for an offense (three, five, or ten years); this also considers the possibility of suspending the limitation period in the event of a new crime.
- Self-defense—a concept that encompasses the absence of time to call for assistance from law enforcement.
- Temporary incapacity for work, temporary absence, temporary residents, temporary workers, etc.—terms that also retain a temporal dimension.
The discussion surrounding "space in law" can be prompted by numerous examples of terms bearing the mark of "spatiality" used in legal documents: place of residence, place of duty execution, place of incarceration, establishing jurisdiction based on residence, and jurisdiction concerning territorial affiliation.
The aforementioned frameworks for the representation of space and time testify to their human dimension, indicating that the perception of nature is inseparable from the general orientation of humanity within the world, which also encompasses phenomena of a social and general cultural nature.
Über den Autor
Dieser Artikel wurde von Sykalo Yevhen zusammengestellt und redigiert — Bildungsplattform-Manager mit über 12 Jahren Erfahrung in der Entwicklung methodischer Online-Projekte im Bereich Philosophie und Geisteswissenschaften.
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Der Inhalt basiert auf akademischen Quellen in mehreren Sprachen — darunter ukrainische, russische und englische Universitätslehrbücher sowie wissenschaftliche Ausgaben zur Geschichte der Philosophie. Die Texte wurden aus den Originalquellen ins Deutsche übertragen und redaktionell bearbeitet. Alle Artikel werden vor der Veröffentlichung inhaltlich und didaktisch geprüft.
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