Philosophy of Chemistry

After the birth of thermodynamics’ second principle—outlined in Carnot's Réflexions sur la puissance motrice du feu —several studies provided new arguments in the field. Mainly, they concerned the thermodynamics’ first principle—including energy conceptualisation—, the analytical aspects of the heat propagation, the statistical aspects of the mechanical theory of heat. In other words, the second half of nineteenth century was marked by an intense interdisciplinary research activity between physics and chemistry: new disciplines applied to the heat developed in the form of (...) analytical, mechanical and statistical theories. Inside all these theories, entropy—the brand-new function that Clausius coined in his Mechanical theory of heat—started to play a central epistemic role. In the present paper, we analyse some steps of the historical process of conceptualisation of such function from 1850 to 1902. Particularly, we retrace the historical–foundational path that—starting from Clausius’ Second Law—lead Boltzmann and Gibbs to their distinguished formulations of statistical entropy. As usual, our research has been unrolled through the analyses of primary sources and by leaning on critical readings of the secondary literature. As for the methodological approach, text analysis of historical documents constituted our privileged modus operandi. This paper is the expression of a collaborative historical research program focused on the thermodynamic foundations of physics–chemistry relationship; early results have already been published by the same authors upon the concepts of reversibility––and––thermal equilibrium. (shrink)

A simple treatment of chemical equilibrium is given, based on Boltzmann’s distribution law. The results are compared with those obtained by using thermodynamics.

In a recent article entitled “The problem of molecular structure just is the measurement problem”, Alexander Franklin and Vanessa Seifert argue that insofar as the quantum measurement problem is solved, the problems of molecular structure are resolved as well. The purpose of the present article is to show that such a claim is too optimistic. Although the solution of the quantum measurement problem is relevant to how the problem of molecular structure is faced, such a solution is not sufficient to (...) account for the structure of molecules as understood in the field of chemistry. (shrink)

No exact definition of an “organic” substance has been agreed upon by the chemical community and textbook definitions vary substantially. The question of what exactly constitutes an “organic” substance is explored in this paper. Various carbon-containing substances that have been by some considered to be “inorganic” are examined in an attempt to ascertain whether carbon in these compounds display different chemical behavior than what is expected of carbon in an “organic” substance. Types of substances considered are carbon allotropes, carbides, carbonates (...) and bicarbonates, cyanide and cyanate ions, carbido clusters, carbon oxides, and compounds without hydrogen.Graphic abstract. (shrink)

Despite the periodic table having been discovered by chemists half a century before the discovery of electronic structure, modern designs are invariably based on physicists’ definition of periods. This table is a chemists’ table, reverting to the phenomenal periods that led to the table’s discovery. In doing so, the position of hydrogen is clarified.

In the Netherlands, the poet Herman Gorter is mostly known as the author of the neo-romantic poem May and the “sensitivistic” Poems, but internationally he became famous as a propagandist of radical Marxism: the author of influential brochures and of an “open letter” to comrade W.I. Lenin in 1920. During the 1890s, Gorter became increasingly dissatisfied with his poetry, considering it as ego-centric, disinterested and “bourgeois”, unconnected with what was happening in the real world. He wanted to put his poetry (...) on a scientific footing, notably by endorsing a dialectical materialist worldview. In the communist society he envisioned, science would become poetry and poetry would become science. In his opus magnum Pan, two terms are rather prominent, namely heelal and kristal. These signifiers not only reflect important themes, but also two friendships which began around 1900, namely with prominent astronomer and marxist Anton Pannekoek and with Ada Prins, the first woman in the Netherlands who acquired a PhD in chemistry, specialised in liquid crystal research. Whereas Ada Prins is mostly remembered as one of Gorter’s secret lovers, she was first and foremost his educated guide into the complex and enigmatic world of twentieth-century chemistry research. Liquid crystal chemistry became an important source of inspiration for Gorter’s work and the main objective of this paper is to demonstrate her influence on Gorter’s Pan as a scientific poem After presenting the two heroes of this paper, and their work in poetry and chemistry respectively, I will analyse the role of liquid crystals in Herman Gorter’s Pan, highlighting important connections with Ada Prins’ research into liquid crystal chemistry. (shrink)

Synthetic biology aims to synthesize novel biological systems or redesign existing ones. The field has raised numerous philosophical questions, but most especially what is novel to this field. In this article I argue for a novel take, since the dominant ways to understand synthetic biology’s specificity each face problems. Inspired by the examination of the work of a number of chemists, I argue that synthetic biology differentiates itself by a new regime of articulation, i.e. a new way of articulating the (...) questions and phenomena it wants to address. Instead of describing actual existing biological systems, the field aims to describe biological possibilities. In the second part I corroborate this hypothesis through a comparison between early research in the field of the origins of life and contemporary synthetic biologists, who are not so much interested in the historical origin of life on Earth, but rather in a universal biology of the possible origins of any life whatsoever. (shrink)

In the accompanying article in this issue Neuss challenges the explanation that was first suggested by Schwarz for how to teach the relative occupation and ionization of atomic orbitals in the atoms of metals in the first transition series. The present article is a response to Neuss’ critique which includes a detailed examination of his claim that there is no conclusive evidence for the view that the scandium and other first transition metal atoms lose 4s electrons in preference to those (...) located in 3d orbitals. (shrink)

There are inherent difficulties in a subject like chemistry particularly the notion of a chemical reaction. In this paper the difficulties are discussed from a teaching and learning perspective and from a history of chemistry perspective. Three teaching/learning studies of the incompleteness of the iron thiocyanate reaction in chemical equilibrium are reviewed and it is shown that a recent historical study of the iron thiocyanate reaction has the potential to challenge the interpretation of the incompleteness of the reaction. This establishes (...) a controversial context where students can be introduced to epistemic thinking, that is, how to interrogate chemistry data and form a conclusion which resonates with what we know about the nature of science. A curriculum suggestion for pre-service chemistry teachers is provided. (shrink)

The statements and arguments based on experimental evidence used to support the claim that the 3d sub-level is below the 4s sub-level in scandium are examined. The flaw in all the arguments is that they assume the order in which the 3d and 4s sub-levels arrange remains the same in both the neutral atom and in its ions. Analysis of the ground and excited states of atomic spectra shows that as the number of electrons relative to the nuclear charge increases, (...) the 3d level moves higher in energy relative to the 4s level. It is perfectly possible that in a neutral scandium atom the 3d sub-level is above the 4s sub-level and that when it ionizes the energy levels simultaneously rearrange during the process. (shrink)

This paper comments on a recent article “Revolutionary poetry and liquid crystal chemistry: Herman Gorter, Ada Prins and the interface between literature and science” by Hub Zwart, in which the author explores the influence of the liquid crystal research of Ada Prins on the epic poem Pan written by her long-time lover Herman Gorter. The present paper reviews the basic science of liquid crystals and explains the connections between the work of Prins and its influence on the poem. Other examples (...) of the use of “liquid crystal” as a literary device are identified from renaissance poetry, and the uses of the metaphor in these poems are analysed from a scientific perspective. From these examples it is suggested that creative concepts from poetry may contain elements of substance that appear in hitherto unrecognised scientific realities. (shrink)

Algorithmic chemistries are often based on a fixed formalism which limits the fragment of chemistry expressible in the domain of the models. This results in limited applicability of the models in contemporary mathematical chemistry and is due to the poor fit between the logic used for model construction and the system being modeled. In this paper, I propose a system-oriented methodology which selects a formalism through a mapping of chemical transformation rules to proof-theoretic structural rules. Using a formal specification framework (...) from the field of artificial chemistry, expressive adequacy is ensured by the choice of logic being based on the system properties to be modeled. To illustrate the methodology, a case study is provided that shows how the proposed approach selects linear logic for modeling resource sensitivity and the proof-theoretic interpretation facilitates translation to a programming language. Since the method results in a plurality of models, I conclude with a discussion on how the proposal contributes to multi-model paradigms in computational pharmacology. (shrink)

Classical atoms—“part-less, ontologically irreducible simples” as the conference flyer puts it—are not the atoms of modern chemistry and analogies with the latter can be construed in various ways. They have figured in the historical development of concepts of chemical affinity but without, as Alan Chalmers and I have independently argued, making any significant contribution to empirically justified theories. A purely combinatorial conception of the formation of compounds by juxtaposing atoms is associated with Daltonian atomism. I review the merits of this (...) idea as a solution to problems posed by developments in early nineteenth century chemistry and go on to suggest that subsequent developments in chemistry are as much in agreement with ideas associated with Aristotle as with the ancient atomists, if not more so. The basic issues can be understood without getting involved in detailed chemistry and I hope what I have to say will be of interest to philosophers concerned with the metaphysics of matter but with no special knowledge of chemistry. (shrink)

This undergraduate textbook introduces some fundamental issues in philosophy of science for students of philosophy and science students. The book is divided into two parts. Part 1 deals with knowledge and values. Chap. 1 presents the classical conception of knowledge as initiated by the ancient Greeks and elaborated during the development of science, introducing the central concepts of truth, belief and justification. Aspects of the quest for objectivity are taken up in the following two chapters. Moral issues are broached in (...) Chap. 4, which discusses some aspects of the use and abuse of science, taking up the responsibilities of scientists in properly conducting their business and decision-makers in their concerns with the import of science for society. Part 2 contrasts the view of scientific progress as the rejecting of old hypotheses and theories and replacing them with new ones, represented by Karl Popper, with the conception of progress as accumulating knowledge, saving as much as possible from older theories, represented by Pierre Duhem. A concluding chapter defends the natural attitude of taking the theories of modern science to be literally true, i.e. realism, in the face of arguments drawn partly from the history of scientific progress in criticism of this stance. (shrink)

In the original publication of the article, the author has identified four belated corrections which are listed below.

How do we refer to chemical substances, and in particular to chemical elements? This question relates to many philosophical questions, including whether or not theories are incommensurable, the extent to which past theories are later discarded, and issues about scientific realism. This chapter considers the first explicit reference to types of colorless air in late-eighteenth-century chemical practice. Reference to a gas by one chemist was generally intended to give others epistemological, methodological, and practical access to the gas. This chapter proposes (...) a causal-descriptive theory of reference for chemical substances. Implications for debates about incommensurability and realism are also briefly noted. (shrink)

Group 3 as Sc–Y–La, rather than Sc–Y–Lu, dominates the literature. The history of this situation, including involvement by the IUPAC, is summarised. I step back from the minutiae of physical, chemical, and electronic properties and explore considerations of regularity and symmetry, natural kinds, and quantum mechanics, finding these to be inconclusive. Continuing the theme, a series of ten interlocking arguments, in the context of a chemistry-based periodic table, are presented in support of lanthanum in Group 3. In so doing, I (...) seek to demonstrate a new way of thinking about this matter. The last of my ten arguments is recast as a twenty-word categorical philosophical statement. (shrink)

All suggested notions of reduction of two scientific theories are critically reviewed and analyzed. In particular those applied to the case of the alleged reduction of Chemistry to Quantum mechanics are examined. Since it is recognized that the weakness of this field of research is the lack of a definition of a scientific theory, it is suggested that a scientific theory is characterized by two choices regarding two dichotomies, that is, the kind of mathematics and the kind of logic. According (...) to this view a reduction is only possible between two theories in which the same choices are shared. As a consequence, only one case of reduction in the history of physics is recognized: physical optics to electromagnetism, a case that is commonly accepted. The other cases of claimed reductions are recognized as impossible, owing to the different choices of the two theories at issue and hence the radical variations in meaning of their shared basic notions. In particular, the claimed reduction of Chemistry to Quantum mechanics is disproved in detail. (shrink)

A large variety of periodic tables of the chemical elements have been proposed. It was Mendeleev who proposed a periodic table based on the extensive periodic law and predicted a number of unknown elements at that time. The periodic table currently used worldwide is of a long form pioneered by Werner in 1905. As the first topic, we describe the work of Pfeiffer, who refined Werner’s work and rearranged the rare-earth elements in a separate table below the main table for (...) convenience. Today’s widely used periodic table essentially inherits Pfeiffer’s arrangements. Although long-form tables more precisely represent electron orbitals around a nucleus, they lose some of the features of Mendeleev’s short-form table to express similarities of chemical properties of elements when forming compounds. As the second topic, we compare various three-dimensional helical periodic tables that resolve some of the shortcomings of the long-form periodic tables in this respect. In particular, we explain how the 3D periodic table “Elementouch”, which combines the s- and p-blocks into one tube, can recover features of Mendeleev’s periodic law. Finally we introduce a topic on the recently proposed nuclear periodic table based on the proton magic numbers. Here, the nuclear shell structure leads to a new arrangement of the elements with the proton magic-number nuclei treated like noble-gas atoms. We show that the resulting alignments of the elements in both the atomic and nuclear periodic tables are common over about two thirds of the tables because of a fortuitous coincidence in their magic numbers. (shrink)

Generally, an object is vague when its properties cannot precisely defined. The ontic view of vagueness is the idea that vagueness is a fundamental property of Nature. This simply means that everything is vague: animals, plants, molecules, atoms, etc. Furthermore, if atoms and molecules are vague, then the subject matter of chemistry is vague. However, we first need to understand why molecules and atoms are vague.

Structure–activity relationship and quantitative SAR are modeling methods largely used in assessing biological properties of chemical substances. QSAR is based on the hypothesis that the chemical structure is responsible for the activity; it follows that similar molecules are expected to have similar properties. Similarity plays an important role in read across, which categorizes molecules primarily on the basis of similarity. Similarity, and chemical similarity too, is a property differently perceived by humans. The various proposed metrics often disagree with human judgment, (...) and no a unique metric for chemical similarity is universally adopted. Researchers argued that categorization is not only explained by similarity but depends as well on abstract knowledge and the task to accomplish. Moreover, similarity cannot be the unique explanation of a categorization, as different perceptual processes take place in category formation. Assuming that similarity judgments are deeply rooted in human knowledge and perception, cognitive sciences contributions are as important as the mathematical considerations of the classical theories. After an excursus in the many views of similarity in philosophy, mathematics, and cognitive science, the paper explores how connectionist systems, which loosely mimic the human cognitive system, could improve similarity-based choices. A case study on building SARs using connectionism and deep neural networks shows the role of similarity in building and explaining those models. A discussion about deep learning for QSAR and as a modeling tool for science concludes the presentation. (shrink)

After briefly presenting the first formulation of the equilibrium constant stated by Guldberg and Waage, this study examines the early thermodynamic and kinetic deductions of the equilibrium law. Firstly, it is discussed how Horstmann applied the concept of entropy to chemical equilibrium reactions, which meant the first thermodynamic explanation of the Guldberg-Waage law of mass action proposed in 1864. A different theoretical derivation of the equilibrium constant came from the works of van’t Hoff. This study analyses the first accurate kinetic (...) treatment of equilibrium reactions as well as van’t Hoff’s imaginative thermodynamic foundation of the constant ratios in chemical equilibrium systems. (shrink)

Chemistry and dynamics are closely related in G.W. Leibniz's thinking, from the corpuscularism of his youth to the theory of conspiracy movements that he proposes in his later years. Despite the importance of chemistry and chemical thought in Leibniz's philosophy, interpreters have not paid enough attention to this subject, especially in the recent decades. This work aims to contribute to filling this gap in Leibnizian studies. In this first part of the work I will expose the theory of matter that (...) the young Leibniz conceives under the influence of chemical corpuscularism. Leibniz uses R. Boyle's interpretation of the Aristotelian idea of form in order to give an explanation of the unity and cohesion of bodies. As opposed to the Cartesians, Leibniz puts forth the idea of a dependence between the variables of extension, movement and figure, without losing analytical clarity and with the aim of extending the explanatory power of physics to natural phenomena difficult to approach by Cartesian mechanics. (shrink)

In the Netherlands, the poet Herman Gorter is mostly known as the author of the neo-romantic poem May and the “sensitivistic” Poems, but internationally he became famous as a propagandist of radical Marxism: the author of influential brochures and of an “open letter” to comrade W.I. Lenin in 1920. During the 1890s, Gorter became increasingly dissatisfied with his poetry, considering it as ego-centric, disinterested and “bourgeois”, unconnected with what was happening in the real world. He wanted to put his poetry (...) on a scientific footing, notably by endorsing a dialectical materialist worldview. In the communist society he envisioned, science would become poetry and poetry would become science. In his opus magnum Pan, two terms are rather prominent, namely heelal and kristal. These signifiers not only reflect important themes, but also two friendships which began around 1900, namely with prominent astronomer and marxist Anton Pannekoek and with Ada Prins, the first woman in the Netherlands who acquired a PhD in chemistry, specialised in liquid crystal research. Whereas Ada Prins is mostly remembered as one of Gorter’s secret lovers, she was first and foremost his educated guide into the complex and enigmatic world of twentieth-century chemistry research. Liquid crystal chemistry became an important source of inspiration for Gorter’s work and the main objective of this paper is to demonstrate her influence on Gorter’s Pan as a scientific poem After presenting the two heroes of this paper, and their work in poetry and chemistry respectively, I will analyse the role of liquid crystals in Herman Gorter’s Pan, highlighting important connections with Ada Prins’ research into liquid crystal chemistry. (shrink)

Is Leibnizian dynamics the New Physics sought in his youth to provide a solution to the problem of body unity/composition? This question can only be answered tentatively. The thesis that I will develop in this second part is that chemical-combinatoria project is not complete without some ideas of dynamics. The idea of form, which since the early Leibniz’s philosophy is projected to give a foundation to the corpuscular theory, only reaches this objective with the theory of conspiring movements that Leibniz (...) develops as the last phase of his dynamics. Within this general objective, this second part develops three secondary issues of importance: Leibniz’s emergent and realistic position, his theory of compounds and the interpretation of the Combinatoria or Characteristica project as a science of forms. (shrink)

Recently, philosophers have come forth with approaches to chemistry based on its actual practice, imparting to it a proper aim and character of its own. These approaches add to the currently growing movement of pluralist philosophies of science. We draw on recent pluralist accounts from chemistry and analyse three notions from modern chemical practice and theory in terms of these accounts, in order to complement the so far more general pluralist approaches with specific evidence. Our survey reveals that the concept (...) of element indicates conceptual pluralisms in chemistry. that electronegativity illustrates methodological pluralism in determining one and the same concept, and that acidity is an instance of plurality hidden behind ‘one notion’. (shrink)

Electron redistribution is the cornerstone of our understanding of chemical reactivity. For the vast majority of organic reactions electrons are assumed to move in pairs providing explanatory mechanisms through the generation of intermediate structures. But for many transformations these discrete steps are idealized constructs, involving intermediates assumed but not empirically justified. This unitary perspective predicated on the curved arrow formalism has resulted in the scenario where for many organic transformations our supposed understanding far surpasses our growing knowledge. Reformulating organic mechanisms (...) to include single electron transfer as a component of, or an alternative to, the prevailing iconic descriptions can provide for a more empirically adequate mechanistic description. In addition using the language of SET presents an opportunity to unify mechanistic concepts under a common donor/acceptor framework. (shrink)

Much has been said about the accuracy of the famous predictions of the Russian chemist Dmitrii Ivanovich Mendeleev, but far less has been written on how he made his predictions. Here we offer an explanation on how Mendeleev used his periodic system to predict both physical and chemical properties of little-known and entirely unknown chemical elements. We argue that there seems to be compelling evidence in favour of Mendeleev genuinely relying on his periodic system in the course of issuing his (...) predictions—a point recently contested by Woody Science after the practice turn in the philosophy, history, and social studies of science, Routledge, Abington, 2014). In particular, by using the known properties of a number of near neighbours of the three entirely unknown elements, we seek to show how the very format of his table enabled it to function as a powerful tool for Mendeleev in arriving at his predicted values. We suggest that Mendeleev’s use of the periodic system in making his prediction gives an illuminative example of what Woody calls “theoretical practices” in science. (shrink)

There has been plenty of empirical evidence which shows that the single-particle picture holds to a good approximation in atomic nuclei. In this picture, protons and neutrons move independently inside a mean-field potential generated by an interaction among the nucleons. This leads to the concept of nuclear shells, similar to the electronic shells in atoms. In particular, the magic numbers due to closures of the nucleonic shells, corresponding to noble gases in elements, have been known to play an important role (...) in nuclear physics. Here we propose a periodic table for atomic nuclei, in which the elements are arranged according to the known nucleonic shells. The nuclear periodic table clearly indicates that nuclei in the vicinity of the magic numbers can be understood in terms of a shell closure with one or two additional nucleons or nucleon holes, while nuclei far from the magic numbers are characterized by nuclear deformation. (shrink)

This article discusses the mathematizing of the chemical periodic system as a grid, which leads to a quadratic function or “binódica function” formed by pairs of periods or binodos. We describe the periodic law as an increasing function of the principal quantum number. It works subject to the dialectical laws that generate; first: gradual quantitative changes:, with “duplication” of periods:. Second: radical quantitative changes:, with the emergence of new quantum transitions, growth and a change in the format of the binodos. (...) We use analytical and graphic methods to mathematize Mendeleev’s law, making the size of the binodos and the continuous series depend on the number of the binode, which is the same quantum number. Likewise, we show a graphic representation, in 2D, of a continuous and self-similar spiral function of the elements, in a geometric growth pattern. (shrink)

The periodic table can be simply demarcated into four classes of metal and four classes of nonmetal. Such a treatment has been obstructed by the traditional view of metalloids as in-between elements; understandable but needless boundary squabbles; and a group-by-group view of the reactive nonmetals. Setting aside these limiting notions reveals some interesting patterns and facilitates teaching and learning the periodic table.

In the original publication of the article under the Acknowledgements section, a contributor name was missed out. The corrected statement should read as follows.

Electronegativity is an important physico-chemical concept to study the chemical structure and reactivity. Although, the conundrum related to measurement of electronegativity still persists. In view of this fact, a simple yet rigorous scale of electronegativity, invoking an inverse relationship with atomic nucleophilicity index, has been proposed for 103 elements of the periodic table. The computed data follows periodicity distinctly satisfying all the sine qua non of a standard scale of electronegativity. Further, electronegativity values display a sound similarity with the standard (...) electronegativity scales validating the suitability of the proposed model. Molecular electronegativities of some polyatomic molecules have also been calculated using the proposed scale of electronegativity.Graphic. (shrink)

A 4-dimensional periodic table of chemical elements is presented. The 120 elements in the n = 8 system are located on vertices of a 4D-cubic lattice and specified by Cartesian coordinates based on the four quantum numbers. Each quantum number is represented by a vector along a different spatial direction in 4D Euclidean space. The 4D PT has a fixed topology governed by Euler–Poincare-type equation and the chemical elements have a fixed connectivity with neighboring elements within the 4D PT. Various (...) geometric transformations by rotations and elongations of vectors enable morphing of one PT to another in a continuum while preserving the 4D topology. The 4D structure exhibits principles of complementarity and zero-cyclic sum in chemical elements. Complementarity enables the extension to n = 9 elements and beyond. The 4D PT of elements extends to isotopes and also to molecules and compounds with the same underlying principles. (shrink)

The concepts of molecular structure and molecular shape are ubiquitous in the chemical literature, where they are often taken as synonyms, with unavoidable drawbacks in chemistry teaching. A third concept, molecular topology, is less frequent but it is a reference term in molecular research domains such as Quantitative Structure–Activity Relationships. The present paper proposes an epistemological analysis of these three notions, aimed at clarifying the nature of their relationship, as well as the contiguities and differences between them. At first, we (...) discuss the various acceptations of the terms molecular structure and molecular shape. Then, we examine some crucial milestones in the history of these concepts and we analyse the relationship between structure, shape and topology from an epistemological viewpoint. We point out the distinguishing features of each concept and we show that their semantic openness, that may be fruitful in a specialized context, turns into a source of incoherence and inaccuracy in the teaching context, fostered by the misleading use of these terms made by textbooks. Eventually, we propose a criterion fit to discriminate between the conceptual domains of molecular shape, molecular structure and molecular topology. (shrink)

This paper considers the nature of a curriculum as presented in formal curriculum documents, and the inherent difficulties of representing formal disciplinary knowledge in a prescription for teaching and learning. The general points are illustrated by examining aspects of a specific example, taken from the chemistry subject content included in the science programmes of study that are part of the National Curriculum in England. In particular, it is suggested that some statements in the official curriculum document are problematic if we (...) expect a curriculum to represent canonical disciplinary knowledge in an unambiguous and authentic manner. The paper examines the example of the requirement for English school children to be taught that chemical reactions take place in only three different ways and considers how this might be interpreted in terms of canonical chemistry and within the wider context of other curriculum statements, in order to make sense of neutralisation and precipitation reactions. It is argued that although target knowledge that is set out as the focus of teaching and learning cannot be identical to disciplinary knowledge, the English National Curriculum offers a representation of chemistry which distorts and confuses canonical ideas. It is suggested that the process of representing the disciplinary knowledge of chemistry as curriculum specifications is worthy of more scholarly attention. (shrink)

This paper considers the nature of a curriculum as presented in formal curriculum documents, and the inherent difficulties of representing formal disciplinary knowledge in a prescription for teaching and learning. The general points are illustrated by examining aspects of a specific example, taken from the chemistry subject content included in the science programmes of study that are part of the National Curriculum in England. In particular, it is suggested that some statements in the official curriculum document are problematic if we (...) expect a curriculum to represent canonical disciplinary knowledge in an unambiguous and authentic manner. The paper examines the example of the requirement for English school children to be taught that chemical reactions take place in only three different ways and considers how this might be interpreted in terms of canonical chemistry and within the wider context of other curriculum statements, in order to make sense of neutralisation and precipitation reactions. It is argued that although target knowledge that is set out as the focus of teaching and learning cannot be identical to disciplinary knowledge, the English National Curriculum offers a representation of chemistry which distorts and confuses canonical ideas. It is suggested that the process of representing the disciplinary knowledge of chemistry as curriculum specifications is worthy of more scholarly attention. (shrink)

One of the foundational problems of biochemistry concerns the conceptualisation of the relationship between the composition, structure and function of macromolecules like proteins. Part of the recent philosophical literature displays a reductionist bias, that is, the endorsement of a form of microstructuralism mirroring an out-dated biochemical conceptualisation. We shall argue that such microstructuralist approaches are ultimately committed to a potentialist form of micro-predeterminism whereby the macrostructure and function of proteins is accounted for solely in terms of the intrinsic properties and (...) potentialities of the components of the primary structure as if they were self-contained or essentially immutable entities. We shall instead suggest that a conceptualisation of the relationship between proteins’ composition, structure and function consistent with contemporary biochemical practice should account also for the causal role of the cellular, organismal and environmental relations in protein development. The analysis of the folding process we propose suggests that microstructure-laden reductionist approaches are ontologically indefensible. Rather than a potentialist form of micro-predeterminism, our analysis ultimately supports a relational-construction-based view of protein development and potentialities formation, which requires an indispensable analysis of the dynamical interplay between the micro-level of the parts and the macro-level of the relational structures of their systems. (shrink)

While temporal considerations are of prime importance for chemical reactions, as well as for molecular stability, most chemical concepts are not explicitly formulated on a diachronic basis. It will be argued here that a formulation explicitly incorporating temporal and epistemological considerations enables us to treat chemical reactions and chemical substances on ontologically equivalent terms, instead of assigning a more fundamental status to the latter. After all, in collision theory, a chemical substance is just a collision complex that takes too long. (...) How long qualifies as “too long”, and “too long” in relation to what, are crucial questions that distinguish chemical substances from chemical reactions, and reversible reactions from irreversible ones, thereby introducing anthropocentric considerations into these distinctions. Too long for a lab chemist is very different from too long for an astrochemist studying chemical reactions between chemical substances in inter-stellar space on cosmological timescales. Examining several physical and chemical properties on the basis of which chemical substances are distinguished from one another, the role of temporal and anthropocentric considerations in defining molecular properties is emphasized. I conclude with some observations on the much-debated reduction of chemistry to other disciplines, arguing that such reduction depends on our aesthetic choices as to what kinds of observations demand explanation, and what kinds of explanation are acceptable. (shrink)

The history of the diffusion and confirmation of Mendeleev’s periodic table of elements has proven to be a challenging testbed for contemporary philosophical debates on the role of predictions in science. More than ten years of fruitful literature came after Scerri and Worrall :407–452, 2001) versus Maher and Lipton ; nevertheless, such a long-lasting debate left quite a few open questions. The aim of this contribution is to go through the various cases that emerged during the debate, in an effort (...) to explain them coherently in a weak predictivist perspective. Maher’s early account—according to which the astounding success of the major predictions alone was enough to explain the confirmation of the periodic table—can now be replaced by a more balanced and thorough picture, where both predictions and accommodations do weight. (shrink)

In recent publications, Harré and Llored Challenges of cultural psychology, Routledge, London, pp 189–206, 2018a; Philosophy, 93:167–186, 2018b; The analysis of practices, Cambridge Scholars Publishing, Newcastle upon Tyne, 2019) take the role of philosophy of science as a digging out of the ‘hinges’, that are the tacit elements of a discipline. In this perspective, the philosophy of chemistry consists, at least partly, in making explicit the hinges on which chemistry turns and in examining their origins and logical status. In this (...) paper, we propose to query Harré and Llored’s research approach in the case study of the element chlorine. Whereas most early nineteenth-century textbooks define the element as the endpoint of chemical decomposition, the controversy surrounding the element chlorine reveals implicit criteria that surpass operational indivisibility. From 1810 onwards, Davy argued that chlorine was a simple substance; yet, even though it had been known to be indecomposable using the strongest instruments available, the widespread acceptance of chlorine took until 1816–1818. The main factor that contributed to the resolution of the debate was the discovery of iodine, an analogous element which provided new theoretical coherence between explanations of different phenomena :247–258, 1959). Thus, the idea that elements should qualitatively resemble each other is an implicit belief which appears to have been shared by many prominent chemists of the time, despite the fact that it was not stated as part of the definition of the chemical element. Could we assert that this idea was a ‘hinge’ around which the notion of chemical element revolved? Our talk will answer this question. (shrink)