{"id":2046,"date":"2023-11-10T11:57:41","date_gmt":"2023-11-10T11:57:41","guid":{"rendered":"https:\/\/www.laspa.slg.br\/?page_id=2046"},"modified":"2023-11-10T11:57:41","modified_gmt":"2023-11-10T11:57:41","slug":"hidrogenio-helio-carbono-nitrogenio-oxigenio-sodio-magnesio-silicio-germanio-bario-enxofre-ferro-e-radio-em-delanda-2010","status":"publish","type":"page","link":"https:\/\/www.laspa.slg.br\/en\/projetos\/a-agencia-social-dos-elementos-quimicos\/levantamentos-da-presenca-de-elementos-quimicos-em-livros\/hidrogenio-helio-carbono-nitrogenio-oxigenio-sodio-magnesio-silicio-germanio-bario-enxofre-ferro-e-radio-em-delanda-2010\/","title":{"rendered":"Hidrog\u00eanio, h\u00e9lio, carbono, nitrog\u00eanio, oxig\u00eanio, s\u00f3dio, magn\u00e9sio, sil\u00edcio, germ\u00e2nio, b\u00e1rio, enxofre, ferro e r\u00e1dio em DeLanda (2010)"},"content":{"rendered":"<p>Let\u2019s begin the comparison of the two ontologies at the atomic scale, that is, with the case in which the genus is \u201cAtom\u201d and the species is \u201c<strong>hydrogen<\/strong>\u201d or \u201c<strong>oxygen<\/strong>\u201d. A modern Aristotelian approach would begin by giving necessary and sufficient conditions to belong to the general category \u201c<strong>hydrogen<\/strong>\u201d, such as possession of a single proton (and a single electron). This is a perfectly reasonable way to specify the [84] identity of this chemical species given that if we added another proton to a <strong>hydrogen<\/strong> atom we would change its identity, transforming it into an atom of <strong>helium<\/strong>. But in Aristotle a species did not just play a role in classifying entities but also in <em>generating<\/em> them. As a good realist, Aristotle knew that he had to explain how objective entities come into existence, in both nature and art. In both cases his explanation involved <em>essences acting as formal causes<\/em>. In nature, Aristotle saw the operation of essences as self-evident, from the observation that a horse begets a horse, and a human a human. In other words, he explained how animal species generate individual organisms by saying that they formally caused them. And similarly for art: in the case of building a house (or nurturing a patient to health) the formal cause is the idea that preexists in the human soul. <\/p>\n<p>Hence, Aristotle argued that a house, or any other entity that \u201cinvolves matter arises, or is generated, from that which does not involve a connection with matter: for the medicinal and the house-building arts are the form, the one of health, and the other of a house. Now, I mean by substance not involving any connection with matter, the essence or very nature or formal cause of a thing.\u201d [Nota de rodap\u00e9 5: Aristotle. The Metaphysics. Op. Cit. p. 142.] This is a much stronger claim than simply saying that possession of a single proton and a single electron is the criterion to belong to the category \u201c<strong>hydrogen<\/strong>\u201d. It is also a claim about what is philosophically significant about the generation of form: the process through which a house is built or a horse embryologically developed involves a connection with matter (immanent) and is therefore not as important metaphysically as the formal essence that is not so connected (transcendent).<\/p>\n<p>In a Deleuzian ontology, on the other hand, an essence operating as a formal cause would not be what defines the identity of an <em>assemblage<\/em> composed of protons and electrons, nor would an essence make questions of <em>processes of assembly<\/em> irrelevant to metaphysics. The minimal definition of the term \u201cassemblage\u201d is that of a whole with properties that are both irreducible and immanent. An assemblage\u2019s properties are irreducible because while they emerge from the actual interaction between its parts, they cannot be ascribed to any of its parts. And they are immanent because if the components of [85] the assemblage ceased to interact its own properties would cease to exist: emergent properties may not depend on this or that particular interaction, on this or that connection with matter, but they do demand that there should be some connection with matter. The emergent chemical properties (and capacities) of an atom, for example, depend on its outermost shell of electrons: whether the shell is missing an electron, or has an extra electron, or is exactly full. This property determines how many bonds an atom can form with other atoms: <strong>carbon<\/strong> atoms can form four; <strong>oxygen<\/strong> ones two; and <strong>hydrogen<\/strong> atoms only one. The properties of the outer shell (and the bonding capacities with which these endow an atom) are clearly not reducible to the properties of individual electrons, but they would cease to exist if those electrons stopped interacting with the atom\u2019s nucleus. <\/p>\n<p>We can summarize this by saying that there is no such thing as \u201c<strong>hydrogen<\/strong> in general\u201d, only a very large population of individual <strong>hydrogen<\/strong> atoms defined by properties that emerge from the continuous interaction among individual components. In other words, each <strong>hydrogen<\/strong> atom is an individual singularity. To the objection that even if each <strong>hydrogen<\/strong> atom is a unique historical entity all <strong>hydrogen<\/strong> atoms are basically the same (they are all defined by a one-proton nucleus) we can answer that there are other components, neutrons, that produce <em>inherent variation<\/em>. Depending on the number of neutrons a <strong>hydrogen<\/strong> nucleus possesses variant isotopes of this chemical species are generated: protium, deuterium, and tritium. The number of neutrons in a nucleus has very little effect on an atom\u2019s chemical properties, but it does affect its physical stability: some isotopes are stable and more enduring, while others decay faster. When we consider not one atom but an entire population of atoms, the relative abundances of isotopes, or more exactly, the statistical form of the distribution of isotopic variation, contains information about the historical processes that produced the members of the population, processes that replace formal causes in this ontology. In other words, the variation is not a trivial side effect but a significant source of knowledge.<\/p>\n<p>Let\u2019s briefly sketch what is known in astrophysics about the production of atoms of different species. Although <strong>hydrogen<\/strong> and <strong>helium<\/strong> were produced under the intense [86] conditions following the Big Bang, the rest of the chemical species had to wait hundreds of millions of years until the formation of stars. Today the nuclei of most atoms are assembled in stars, so the process of assembly is known as <em>stellar nucleosynthesis<\/em>. Stars of different sizes serve as assembly factories for atoms of different species: the larger and hotter the star the heavier the atoms it can put together. The smaller stars, like our Sun, are only hot enough (10 million degrees Kelvin) to burn <strong>hydrogen<\/strong> as fuel and produce <strong>helium<\/strong> as a product. At higher temperatures (over 100 million degrees), <strong>helium<\/strong> itself can be burnt as fuel and yield as products <strong>carbon<\/strong>, <strong>oxygen<\/strong>, and <strong>nitrogen<\/strong>. At even higher intensities (a billion degrees) <strong>carbon<\/strong> and <strong>oxygen<\/strong> become the fuel, while the products are atoms of the species: <strong>sodium<\/strong>, <strong>magnesium<\/strong>, <strong>silicon<\/strong> and <strong>sulfur<\/strong>. As intensities continue to increase <strong>silicon<\/strong> is burned as fuel to produce iron, and finally a maximum of intensity is reached in the process of explosive nucleosynthesis, in which the heavier species are created during the violent events known as \u201csupernovae\u201d. [Nota de rodap\u00e9 6: Stephen F. Mason. Chemical Evolution. (Oxford: Clarendon Press, 1992), Chapter 5.] <\/p>\n<p>We can imagine that, confronted with this information, Aristotle would be unimpressed, since he could argue that the details of how a house is built, or a patient healed, or an atom assembled, are less important than their formal causes. In particular, he could argue that regardless of what happens in stars, only a certain number of atomic species exists, a number that can be considered to have existed prior to any process of nucleosynthesis. There is, in fact, some truth to this objection which is why we need to add to an ontology of individual singularities the universal singularities that structure the space of possible species. Let\u2019s first consider this space as given in the famous Periodic Table of the Elements. The table itself has a colorful history because several scientists had already discerned regularities in the properties of the chemical species (when ordered by atomic weight) prior to Mendelev stamping his name on the table in 1869. Several decades earlier, for example, one scientist had already seen a simple arithmetical relation between triads of elements, and later on others noticed that certain properties (like chemical reactivity) recurred every seventh or eighth element. In other words, rhythms or periodically recurrent regularities had been observed pointing to the existence of a deeper structure. What constitutes Mendelev&#8217;s great achievement [87] is that he was the first one to have the courage to leave <em>open gaps<\/em> in the table instead of trying to impose an artificial closure on it. This matters because in the 1860&#8217;s only around sixty species had been isolated, so the holes in Mendelev&#8217;s table were like daring predictions that yet undiscovered species had to exist. He predicted, for example, the existence of <strong>germanium<\/strong> on the basis of a gap near <strong>silicon<\/strong>. The Curies later on predicted the existence of <strong>radium<\/strong> on the basis of its neighbor <strong>barium<\/strong>. [Nota de rodap\u00e9 7: P. W. Atkins. The Periodic Kingdom. (New York : Basic Books, 1995), Chapter 7. p. 72-73.] These risky predictions, and their eventual corroboration, is what gave the table its objective status. But what accounts for the underlying rhythms at the chemical heart of matter? (DeLanda 2010:83-7)<\/p>\n<p>DELANDA, Manuel. 2010. <em>Deleuze: History and Science<\/em>. New York: Atropos Press.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Let\u2019s begin the comparison of the two ontologies at the atomic scale, that is, with the case in which the genus is \u201cAtom\u201d and the species is \u201chydrogen\u201d or \u201coxygen\u201d. A modern Aristotelian approach would begin by giving necessary and sufficient conditions to belong to the general category \u201chydrogen\u201d, such as possession of a single proton (and a single electron). [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":1212,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-2046","page","type-page","status-publish","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/pages\/2046","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/comments?post=2046"}],"version-history":[{"count":1,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/pages\/2046\/revisions"}],"predecessor-version":[{"id":2047,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/pages\/2046\/revisions\/2047"}],"up":[{"embeddable":true,"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/pages\/1212"}],"wp:attachment":[{"href":"https:\/\/www.laspa.slg.br\/en\/wp-json\/wp\/v2\/media?parent=2046"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}