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According to its Greek etymology ( a-tomos , “indivisible”), the term atomism denotes the general assumption that an area consists of smallest, fundamental, indivisible or reducible elements.

The most widespread use of the term is in the context of natural philosophy , metaphysics, and cosmology , with a certain continuity from pre-Socratic assumptions of less material elements to the atomic concept of modern particle physics. Atomism is also used in other contexts when the smallest, inexplicable or reducible theoretical concepts or objects of reality are described, for example if fundamental semantic units are assumed , as is the case here. a. the logical atomism developed (see also elementary theorem ).

Natural philosophical atomism


The atomism , the atomistic called denotes a cosmological theory, according to which the universe from the smallest particles, the atoms (Greek átomos that Unzerschneidbare, indivisible) is composed, which in completely empty move space. These atoms were thought to be discrete (i.e., separable from one another), infinitely hard , immutable, and eternal . It is in contrast to the conception, for example of the Eleates , of matter as a continuum . Atomism emerged in Greece in the fifth century BC, mainly through Leucippus and Democritus as the first representatives of the philosophical school of Abdera . Democritus was the pupil of Leukippus who actually founded atomism, and their contributions are difficult to separate. Democrit's central statement on this is:

“A thing only appears to have a color; it only appears to be sweet or bitter; in reality there are only atoms and empty space. "

According to Democritus, the atoms differed quantitatively in shape and size, but were made from the same original substance. Observable changes resulted from different combinations of atoms, but they remained unchanged. In the fourth century, Epicurus developed the teaching further. Lucretius ' didactic poem De rerum natura ( About the nature of things , around 55 BC) gives a coherent representation of this materialistic worldview in Latin.

Other ancient forms of atomism, in contrast to Democritus, assumed qualitatively different forms of atoms, for example Anaxagoras , in which there were as many different atoms as there were observable substances, or Empedocles , where the atoms of the four elements fire, water, air and earth were qualitatively different. This idea was also represented by Plato , in which the atoms of fire were tetrahedra, those of air octahedron, water icosahedron and earth cubes. In addition, with other ancient atomists the atoms were not necessarily indivisible, they only became atoms of another substance, except for Anaxagoras, where they could be divided as often as desired but remained of the same kind ( homoiomeries ). The historically most important of these variants is that of the commentators of Aristotle ( Alexander von Aphrodisias , Themistios , Johannes Philoponos ), who called the atoms elachista what was called minima in Latin literature . In his natural philosophy Aristotle distinguished between matter and form and accordingly atoms were also changeable in his case. He did not publish his own atomic theory (this was later adopted by his commentators, doctrine of minima naturalia ), but criticized Anaxagora's infinite divisibility, for Aristotle there was a limit (specific to the individual substances).

Heron of Alexandria was also influential in later times (edition by Federico Commandino , 1575) with his emphasis on the role of the vacuum between particles.

There is also an atomic theory (possibly going back to Greek tradition) in India ( Vaisheshika of Canada ).

middle Ages

In the Middle Ages, the knowledge of Greek atomic theory survived among Arabic or Arabic-writing and Jewish authors (such as Maimonides , who reported on Arabic atomistics), Christian criticism (such as that of Dionysius of Alexandria ) and copyists of ancient manuscripts such as that of Lucretius About the Nature of things in the monasteries. In the 6th century, the encyclopaedist Isidore of Seville distinguished atoms from matter, time, space and other things. With the Arabs, for example, Rhazes represented atomistic ideas. Overall, however, there was no significant new development in atomic science up to the Renaissance. Accordingly, atomistic ideas found their way into regions that had contact with the Arab region, such as southern Italy, such as Alfanus von Salerno (application to medicine) and pseudo-donors (Summa perfectionis magisteriis).

In the 15th century, ancient writings such as Lucretius were rediscovered and printed by Renaissance scholars, with much greater circulation. Nikolaus von Kues also drew attention to the Greek atomists.

Early modern age

While with Aristotle and his Hellenistic commentators the minima naturalia denoted a theoretical limit of divisibility, with the Arab commentators of the school of Averroes like Agostino Nifo in the Renaissance he assumed the role of real building blocks of matter and chemical reactions also took place between these minima (atoms ) from. Julius Caesar Scaliger attributed the different properties of rain, snow and hail to different distances and configurations of the same atoms (those of water). According to Scaliger, chemical reactions were the contact of atoms, which leads to a bond ( Exercitationes 1557). The atomic theory (minima) was widespread among the Aristotelians of the Renaissance. While, for example, the differences between philosophical schools still played a role with Scaliger, in the 17th century there was increasing interest in their function in explaining natural phenomena. Among the early chemists, Daniel Sennert (he distinguished between atoms of elements and atoms of compounds, prima mista ) and Robert Boyle advocated the spread of atomistics. At the beginning of the 17th century the knowledge of Greek atomic theory was so widespread that William Shakespeare had Celia say in 1601 in Was ihr wollt (Act 3, Scene 2): It is as easy to count atomies as to resolve the propositions of a lover (Refusal of counting atoms as something beyond human capabilities). Early representatives of atomism were Thomas Harriot (research on optics, contacts with Kepler), Giordano Bruno (who influenced Kepler and whose theory of monads influenced Gottfried Wilhelm Leibniz ), Francis Bacon (heat as the movement of atoms) and Johannes Kepler (in his treatise on snow crystals in which he traces their hexagonal symmetry back to the closest packing of spheres of the atoms that make them up, but did not refer to the Greek atomists). The doctor Johann Chrysostom Magnenus published a book on atomism (Democritus reviviscens) in 1646.

At the end of the 1640s, Pierre Gassendi followed the Epicureans and with them Democritus, but adapted atomic theory to the requirements of the time, which wanted to assign physical and chemical properties to atoms. These could not be qualitatively the same as with Democritus, which Gassendi achieved by postulating that initially molecules formed from the original atoms and that these were then responsible for the qualitative differences. Gassendi also freed atomic theory from its connection to materialism, making it more acceptable to contemporaries.

René Descartes suggested the connection to mechanics around 1640. For him there was no indivisibility of matter (which for him was spatial expansion), but infinitely small particles in the ether . He assigned dynamic properties (speed, mass) to these parts of matter. Its corpuscles could therefore be used in mechanical theories. Robert Hooke attributed the regular structure of crystals to the arrangement of atoms and heat to their movement, and Christiaan Huygens , following Gassendi, saw matter of small, hard particles in rapid motion and applied this to optics, for example (light was for him Wave motion of particles) and cohesion. Isaac Newton contributed a lot to the acceptance of atomism , especially with his book Opticks (1704). According to Newton, the smallest parts of matter are indivisible, hard and of a certain size and shape. Whether he viewed them as equal to one another is often assumed, but was never expressed in that way by Newton himself. Between them is empty space (in contrast to the Cartesians it consists of a vacuum similar to that of the Greek atomists) and forces act in a repulsive and attractive manner between them. Newton mostly avoided speculation about the exact nature of the forces and the smallest particles, as he did with them rejected the Cartesians or Hooke, but occasionally did mention them, for example in his Opticks or his letter to Boyle in 1679. Basically, he considered it the task of future generations to fathom the nature of the forces between the atoms and only looked at their properties speak so far as they could be deduced from observation in his opinion. In the Principia, Book III, Rule III it says:

The expansion, hardness, impenetrability, mobility and inertia of the whole comes from the expansion, hardness, impenetrability, mobility and inertia of the parts and we therefore conclude that the smallest particles of all bodies are also expanded, hard, impenetrable, agile and endowed with their own inertia are. And that is the basis of all philosophy (The extension, hardness, impenetrability, mobility and inertia of the whole results from the extension, hardness, impenetrability, mobility and inertia of the parts and hence we conclude that the least particles of all bodies to be all extended, and hard and impenetrable and movable and endowed with their proper inertia. And that is the foundation of all philosophy).

In addition, they are subject to the universal attractive force of gravity, even if, in contrast to inertia, he does not see this as an essential property of bodies. The Principia was therefore regarded as a book that gave expression to the atomism, which was already widespread at the time, and at the same time Newton was one of the first to draw initial quantitative conclusions from it. In his Opticks , for example, Newton derived an upper limit of centimeters in diameter for soap particles from the optical properties of soap bubbles, and he believed that he derived Boyle's gas law in his Principia from a model of hard particles that exert repulsive forces on one another. He gave more detailed insight into his idea of ​​the structure of matter in a conversation with David Gregory , according to which the basic units built hierarchically larger structures, which he preferred to a lattice structure in the explanation of chemical reactions. Ruder Boskovic ( Philosophiae naturalis theoria ) followed Newton in 1758 with atoms as mathematical points between which forces act.

Robert Boyle, who was influenced by Descartes and Gassendi and who published an essay on atomism in 1670 (About the excellency and grounds of the mechanical hypothesis), was more interested in the chemical properties, but was also aware that the knowledge of chemistry at the time ( how the working of Paracelsian three principles according to the teachings of alchemy or the teaching of four elements) were not sufficient for a chemical atomic theory. Like Sennert, he distinguished between atoms of compounds ( primary concretions ) and elementary atoms. Basically, he started from a structure of elementary atomic building blocks of the same type, which were put together to form differently shaped structures that explained their chemical and macroscopic properties. But that was not enough for the chemists, and theories arose in which the atoms were different and had special shapes, even hooks and eyes ( Nicolas Lémery ) and also old alchemical classifications of substances were again incorporated into the characterization of the atoms. This also happened with the founder of the phlogiston theory, Georg Ernst Stahl , who, like Boyle, was an atomist and introduced a fluid-like substance, the phlogiston, to explain the combustion processes.

Progress was made here by the further development of chemistry in the 18th century, in particular by Antoine de Lavoisier with today's operational definition of the concept of elements and the introduction of quantitative methods into chemistry (precise weighing, determination of the amount of heat). He himself also adhered to premodern conceptual formations such as warmth and stated in his textbook on chemistry from 1789 that all statements about atoms are pure metaphysics, because nothing can be experimentally expressed about their nature, but more detailed investigations of his posthumous writings have meanwhile been carried out show that he too was on the way to an atomic theory of matter and attributed the heat to a repulsive force between the molecules, and counteracted an attractive force (gravitation) that held the bodies together.

19th century and after

The decisive step towards a well-founded chemical atomic theory was taken by John Dalton , who extended Joseph-Louis Proust's law of constant proportions (1797) to the law of multiple proportions . From this he drew the conclusion that every element consists of identical, unchangeable atoms that can combine with each other in fixed numerical proportions and thus form the smallest particles of substances (later called molecules ), which are not pure elements but chemical compounds. He published this view in 1808 with the work A New System of Chymical Philosophy . The atomic hypothesis, which had been purely speculative for thousands of years, was thus placed on a scientific basis, because for the first time measurable properties could be ascribed to atoms. The first relative atomic weights were determined from the weight ratios of the substances that react with one another (Dalton, Jöns Jakob Berzelius ). In 1815, William Prout made a significant contribution with his hypothesis that the atomic masses were integer multiples of the mass of hydrogen and that the atoms of all elements could be composed of hydrogen atoms (an anticipation of the structure of the nucleus from protons and neutrons). Even then, this contradicted the measurements of the atomic mass. Amadeo Avogadro ( Avogadro's law , Avogadro constant ) and Joseph Loschmidt ( Loschmidt constant 1865) made contributions to the concrete determination of atomic sizes in the 19th century . A certain confusion in the distinction between atoms and molecules in the determination of atomic mass was cleared up by Stanislao Cannizzaro . In 1834 Michael Faraday discovered with the help of electrolysis that atoms can also carry a certain electrical charge. New elements were constantly being discovered by chemists, which finally culminated in the periodic table around 1867, which indicated a systematic structure of the atoms. In 1875 Ludwig Boltzmann concluded from measurements on mercury vapor that its atoms show up as perfect mass points within the framework of the kinetic gas theory . The composition of the atoms from smaller components was derived from spectroscopic investigations on gases, with the electron being the first elementary particle to be identified in 1897 ( Joseph John Thomson , Hendrik Antoon Lorentz ). In the late 19th century there was fundamental criticism of the atomic concept in German-speaking countries by the energetic engineer Wilhelm Ostwald and his students, and the physicist and positivist philosopher Ernst Mach , which led to a heated controversy with Boltzmann. It was not until the beginning of the 20th century that Albert Einstein and Jean Perrin provided the physical proof of the atomic concept through their work on statistical fluctuation phenomena (such as diffusion and Brownian motion ).

Instead of a description using unchangeable atoms, a description using a system of elementary particles such as quarks and electrons emerged in physics in the 20th century . After the atom had already been recognized as composed ( Rutherford's atomic model ), this continued with other particles previously considered to be elementary. In quantum mechanics, according to charge and mass (the non-integer values ​​for atomic masses found by chemists in the 19th century had meanwhile been explained by the discovery of isotopes ), other physical quantities were also built up from the smallest units depending on the system found ( quantization ). Elementary particles were no longer viewed as immutable, for example the electron, which is stable against decay according to current knowledge, can be converted into a photon by colliding with its antiparticle ( positron ) and similar processes are possible with other elementary particles, a finding that was temporarily made in the 1960s led to the concept of fundamental particles being questioned as a whole ( nuclear democracy , Geoffrey Chew ). The “zoo” of elementary particles was also constantly expanding the higher one went in the energy scale of the scattering processes with which the elementary particles were examined, and it is open, but not very likely, that the current Standard Model is the end of the description.

Logical atomism

The logical atomism is an early position within the analytical philosophy and was especially by Bertrand Russell represented. According to him, the world should consist of atomic facts that are represented in atomic sentences.

Linguistic Atomism

The term linguistic atomism describes (polemically) a non-structural investigation of linguistic units as isolated, atomized elements without considering structural relationships and dependencies.

Ontological or conceptual atomism (Moore)

George Edward Moore represented an ontological atomism in the form of a conceptual atomism , according to which reality is built up from the smallest, simple components in the form of concepts.

Atomism as opposed to holism

In the present, atomism is contrasted with holistic thinking or holism . Both are categories to describe the relationship between totality and detail when considering complex systems . The on Aristotle goes back set of the Übersummativität ( The whole is the sum of its parts more ), for example, has in the biology indicates that life phenomena can not be reduced to physical and chemical processes, so do not be dismantled within the meaning of atomism.

See also


  • Antonio Clericuzio : Elements, Principles and Corpuscles. A Study of Atomism and Chemistry in the Seventeenth Century , Springer 2000
  • Robert Hugh Kargon: Atomism in England from Hariot to Newton , Oxford: Clarendon Press 1966.
  • René Kayser: The original movement of the atoms in Leukippus and Democritus. A study of the relationship between ontology and physics in Abderitic materialism. Publications de la Société luxembourgeoise de philosophie 1997.
  • Friedrich Albert Lange : History of Materialism (1866), Frankfurt am Main 1974 ( ISBN 3-518-07670-1 ).
  • Kurd Laßwitz : History of Atomistics from the Middle Ages to Newton. I-II, Hamburg and Leipzig 1890 (reprinted Darmstadt 1963). Volume 1, Archives , Volume 2
  • Andrew GM van Melsen: Atomism (1967), in: Donald Borchert, Encyclopedia of Philosophy, Macmillan, Thomson / Gale 2006
  • Lancelot Law Whyte: Essay on Atomism , Wesleyan University Press 1961
Collection of sources on ancient atomism

Web links

Individual evidence

  1. ^ Wilhelm Capelle : The pre-Socratics , fragments and source reports - Leipzig: Kröner, 1935. (Kröner's pocket edition, Volume 119) - p. 135
  2. Illustration based on van de Melde, Atomism, Encyclopedia of Philosophy 2006
  3. Michael E. Marmura: Avicenna and the Kalam . In: Journal of the History of Arab-Islamic Sciences. Volume 7, 1991/1992, pp. 172-206.
  4. Bernhard Dietrich Haage: The corpuscular theory in Geber latinus. In: Würzburger medical history reports 12, 1994, pp. 19–28.
  5. Pietro Omodeo, Minimum and Atom: An expansion of the term in Bruno's reception of Cusanus, in: Tom Müller, Matthias Vollet (eds.): Die Modernitäten des Nikolaus von Kues, Bielefeld 2013, pp. 289–308
  6. ^ Van Melsen, Atomism, in Borchert, Encyclopedia of Philosophy
  7. ^ Newton, Principia, Book III, Rule III, in the edition by Florian Cajori, University of California Press 1934, 1973, Volume 2, p. 399
  8. ^ Newton, Principia, ed. Cajori, Volume 2, 1934, p. 399
  9. Kargon: Atomism in England from Hariot to Newton, Oxford: Clarendon Press 1966, p 131st
  10. ^ Newton, Principia, Book 2, Section 5
  11. ^ Gregory, Diary, December 21, 1705. Quoted in Whyte, Essay on atomism, p. 52
  12. An example of a hierarchical structure of matter from cells with atoms and emptiness is given by Newton in Opticks, Book 2, Part 3, Proposition 8. Presented in Karin Figala, Newton's alchemical studies and his idea of ​​the atomic structure of matter , Appendix A to AR Hall, Newton, Adventuer in Thought, Cambridge UP 1992, pp. 382ff. Harmonious relationships play a role in the distribution.
  13. ^ Strube, Georg Ernst Stahl, Teubner, 1984, p. 45
  14. Marco Beretta, Lavoisier Article, Dictionary of Scientific Biography , Volume 4, 2008, p. 213. He particularly refers to Lavoisier's posthumous memoir .
  15. Ulrich, Linguistische Grundbegriffe, 5th ed. (2002): Atomismus.
  16. See E. Kanterian, Analytical Philosophy , Frankfurt a. M., Campus, 2004, p. 30