T. H. Morgan, A. H. Sturtevant, H. J. Muller and C. B. Bridges published their comprehensive treatise "The Mechanism of Mendelian Heredity" in 1915. By 1920 Morgan 's "Chromosome Theory of Heredity" was generally accepted by geneticists in the United States, and by British geneticists by 1925. By 1930 it had been incorporated into most general biology, botany, and zoology textbooks as established knowledge. In this paper, I examine the reasons why it was accepted as part of a series of (...) comparative studies of theory-acceptance in the sciences. In this context it is of interest to look at the persuasiveness of confirmed novel predictions, a factor often regarded by philosophers of science as the most important way to justify a theory. Here it turns out to play a role in the decision of some geneticists to accept the theory, but is generally less important than the CTH's ability to explain Mendelian inheritance, sex-linked inheritance, non-disjunction, and the connection between linkage groups and the number of chromosome pairs; in other words, to establish a firm connection between genetics and cytology. It is remarkable that geneticists were willing to accept the CTH as applicable to all organisms at a time when it had been confirmed only for Drosophila. The construction of maps showing the location on the chromosomes of genes for specific characters was especially convincing for non-geneticists. (shrink)

Attempts to explain the periodic system as a manifestation of regularities in the structure of the atoms of the elements are as old as the system itself. The paper analyses some of the most important of these attempts, in particular such works that are historically connected with the recognition of the electron as a fundamental building block of all matter. The history of the periodic system, the discovery of the electron, and ideas of early atomic structure are closely interwoven and (...) transcend the physics–chemistry boundary. It is pointed out that J. J. Thomson's discovery of the electron in 1897 included a first version of his electron atomic model and that it was used to suggest how the periodic system could be understood microphysically. Thomson's theory did not hold what it promised, but elements of it were included in Niels Bohr's first atomic model. In both cases, Thomson's and Bohr's, the periodic system played an important role, heuristically as well as justificatory. (shrink)

Dmitrii Mendeleev’s periodic system is known for its predictive accuracy, but talk of its completeness is rarer. This is surprising because completeness was a quality that Mendeleev saw as important for a systematization of the chemical elements. Here, I explain how Mendeleev’s valuing of completeness influenced the development of his periodic system. After introducing five indicators of its completeness, I zoom into one in particular: Mendeleev’s inclusion of a schematic row of oxides. I then show how it guided Mendeleev’s predictions (...) of indium and ekaboron, which suggests that the valuing of completeness was instrumental for making predictions. (shrink)

Many philosophers have argued that a hypothesis is better confirmed by some data if the hypothesis was not specifically designed to fit the data. ‘Prediction’, they argue, is superior to ‘accommodation’. Others deny that there is any epistemic advantage to prediction, and conclude that prediction and accommodation are epistemically on a par. This paper argues that there is a respect in which accommodation is superior to prediction. Specifically, the information that the data was accommodated rather than predicted suggests that the (...) data is less likely to have been manipulated or fabricated, which in turn increases the likelihood that the hypothesis is correct in light of the data. In some cases, this epistemic advantage of accommodation may even outweigh whatever epistemic advantage there might be to prediction, making accommodation epistemically superior to prediction all things considered. (shrink)

This article focuses on the Russian chemist Dmitri Ivanovich Mendeleev's assessment of certain representations of various aspects of the periodic system that employed more mathematical methodology. The equations of interest were created by E. J. Mills, B. N. Chicherin, and J. H. Vincent. The English chemist Mills tried to find a firmer numerical basis for the periodicity of the elements. The Russian lawyer and political philosopher Chicherin was convinced of the existence of a mathematical law underlying the periodic system. The (...) English physicist Vincent explored the connection between atomic weights and the elements' order in listings based on atomic weights—a project which he associated with the periodic system of elements. Although, for Mendeleev, the equations of Mills, Chicherin, and Vincent promised a more precise expression of the law of periodicity, he continued to invoke his earlier standards. In particular, Mendeleev wanted the equations to respect the individuality of the elements, and called for completeness in conveying the complexities of chemical phenomena. Thus, the very qualities that he had valued while developing his periodic system in 1869–1871 also characterised his evaluation of the new means of representing aspects of that system. (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)

This is a comment on the paper by Barnes and the responses from Scerri and Worrall, debating the thesis that a fact successfully predicted by a theory is stronger evidence than a similar fact known before the prediction was made. Since Barnes and Scerri both use evidence presented in my paper on Mendeleev’s periodic law to support their views, I reiterate my own position on predictivism. I do not argue for or against predictivism in the normative sense that philosophers of (...) science employ, rather I describe how scientists themselves use facts and predictions to support their theories. I find wide variations, and no support for the assumption that scientists use a single ‘Scientific Method’ in deciding whether to accept a proposed new theory.Keywords: Predictivism; Novel predictions; Accommodation; Periodic law; Periodic table; Dmitri Mendeleev. (shrink)

A selective history of the benzene problem is presented, starting with August Kekulé's proposal of a hexagonal structure in 1865 and his hypothesis of 1872 that the carbon–carbon bonds oscillate between single and double. Only those theories are included that were accepted or at least discussed by a significant number of chemists. Special attention is given to predictions, their empirical tests, and the effect of the outcomes of those tests on the reception of the theories. At the end of the (...) period covered by this article, chemists generally accepted the valence bond theory proposed by Linus Pauling; some of them considered this a more sophisticated version of Kekulé's oscillation hypothesis. The sequel describes the replacement of the valence bond theory by the molecular orbital theory in the period ending around 1980. (shrink)

In The Paradox of Predictivism I tried to demonstrate that there is an intimate relationship between predictivism and epistemic pluralism. Here I respond to various published criticisms of some of the key points from Paradox from David Harker, Jarret Leplin, and Clark Glymour. Foci include my account of predictive novelty, the claim that predictivism has two roots, the prediction per se and predictive success, and my account of why Mendeleev’s predictions carried special weight in confirming the Periodic Law of the (...) Elements. (shrink)

The debate about the relative epistemic weights carried in favour of a theory by predictions of new phenomena as opposed to accommodations of already known phenomena has a long history. We readdress the issue through a detailed re-examination of a particular historical case that has often been discussed in connection with it—that of Mendeleev and the prediction by his periodic law of the three ‘new’ elements, gallium, scandium and germanium. We find little support for the standard story that these predictive (...) successes were outstandingly important in the success of Mendeleev's scheme. Accommodations played an equal role—notably that of argon, the first of the ‘noble gases’ to be discovered; and the methodological situation in this chemical example turns out to be in interesting ways different from that in other cases—invariably from physics—that have been discussed in this connection. The historical episode when accurately analysed provides support for a different account of the relative weight of prediction and accommodation—one that is further articulated here. (shrink)

Predictivism is the view that successful predictions of “novel” evidence carry more confirmational weight than accommodations of already known evidence. Novelty, in this context, has traditionally been conceived of as temporal novelty. However temporal predictivism has been criticized for lacking a rationale: why should the time order of theory and evidence matter? Instead, it has been proposed, novelty should be construed in terms of use-novelty, according to which evidence is novel if it was not used in the construction of a (...) theory. Only if evidence is use-novel can it fully support the theory entailing it. As I point out in this paper, the writings of the most influential proponent of use-novelty contain a weaker and a stronger version of use-novelty. However both versions, I argue, are problematic. With regard to the appraisal of Mendeleev’ periodic table, the most contentious historical case in the predictivism debate, I argue that temporal predictivism is indeed supported, although in ways not previously appreciated. On the basis of this case, I argue for a form of so-called symptomatic predictivism according to which temporally novel predictions carry more confirmational weight only insofar as they reveal the theory’s presumed coherence of facts as real. (shrink)

There is considerable disagreement about the epistemic value of novel predictive success, i.e. when a scientist predicts an unexpected phenomenon, experiments are conducted, and the prediction proves to be accurate. We survey the field on this question, noting both fully articulated views such as weak and strong predictivism, and more nascent views, such as pluralist reasons for the instrumental value of prediction. By examining the various reasons offered for the value of prediction across a range of inferential contexts , we (...) can see that neither weak nor strong predictivism captures all of the reasons for valuing prediction available. A third path is presented, Pluralist Instrumental Predictivism; PIP for short. (shrink)

Predictivists use the no miracle argument to argue that “novel” predictions are decisive evidence for theories, while mere accommodation of “old” data cannot confirm to a significant degree. But deductivists claim that since confirmation is a logical theory-data relationship, predicted data cannot confirm more than merely deduced data, and cite historical cases in which known data confirmed theories quite strongly. On the other hand, the advantage of prediction over accommodation is needed by scientific realists to resist Laudan’s criticisms of the (...) no miracle argument. So, if the deductivists are right, the most powerful argument for realism collapses. There seems to be an inescapable contradiction between these prima facie plausible arguments of predictivists and deductivists; but this puzzle can be solved by understanding what exactly counts as novelty, if novel predictions must support the no miracle argument, i.e., if they must be explainable only by the truth of theories. Taking my cues from the use-novelty tradition, I argue that (1) the predicted data must not be used essentially in building the theory or choosing the auxiliary assumptions. This is possible if the theory and its auxiliary assumptions are plausible independently of the predicted data, and I analyze the consequences of this requirement in terms of best explanation of diverse bodies of data. Moreover, the predicted data must be (2) a priori improbable, and (3) heterogeneous to the essentially used data. My proposed notion of novelty, therefore, is not historical, but functional. Hence, deductivists are right that confirmation is independent of time and of historical contingencies such as if the theorist knew a datum, used it, or intended to accommodate it. Predictivists, however, are right that not all consequences confirm equally, and confirmation is not purely a logical theory-data relation, as it crucially involves background epistemic conditions and the notion of best explanation. Conditions (1)–(3) make the difference between prediction and accommodation, and account for the confirming power of theoretical virtues such as non ad-hocness, non-fudging, non-overfitting, independence and consilience. I thus show that functional novelty (a) avoids the deductivist objections to predictivism, (b) is a gradual notion, in accordance with the common intuition that confirmation comes in degrees, and (c) supports the no miracle argument, so vindicating scientific realism. (shrink)

Historians and philosophers of science generally conceptualize scientific progress to be dichotomous, viz., experimental observations lead to scientific laws, which later facilitate the elaboration of explanatory theories. There is considerable controversy in the literature with respect to Mendeleev’s contribution to the origin, nature, and development of the periodic table. The objectives of this study are to explore and reconstruct: a) periodicity in the periodic table as a function of atomic theory; b) role of predictions in scientific theories and its implications (...) for the periodic table; and c) Mendeleev’s contribution: theory or an empirical law? The reconstruction shows that despite Mendeleev’s own ambivalence, periodicity of properties of chemical elements in the periodic table can be attributed to the atomic theory. It is argued that based on the Lakatosian framework, predictions play an important role in the development of scientific theories. In this context, Mendeleev’s predictions played a crucial role in the development of the periodic table. Finally, it is concluded that Mendeleev’s contribution can be considered as an “interpretative” theory which became “explanatory” after the periodic table was based on atomic numbers.Author Keywords: Periodic table; Mendeleev’s contribution; Theory; Empirical law; Interpretative theory. (shrink)

In this paper I comment on a recent paper by [Scerri, E., & Worrall, J. . Prediction and the periodic table. Studies in History and Philosophy of Science, 32, 407–452.] about the role temporally novel and use-novel predictions played in the acceptance of Mendeleev’s periodic table after the proposal of the latter in 1869. Scerri and Worrall allege that whereas temporally novel predictions—despite Brush’s earlier claim to the contrary—did not carry any special epistemic weight, use-novel predictions did indeed contribute to (...) the acceptance of the table. Although I agree with their first claim, I disagree with their second. In order to spell out my disagreement, I not only revisit Scerri and Worrall’s interpretation of crucial historical evidence they have cited in support of the ‘heuristic account’ of use-novel predictions, but I also criticise the latter on general grounds.Keywords: Periodic table; Dmitri Mendeleev; Noble gases; Use-novel predictions; Heuristic account; Ad hoc hypotheses. (shrink)

: In this paper I argue that belief in the greater confirmatory value of prediction over accommodation can best be understood as a function of the practice rather than the logic of science. Attempts to account for this asymmetry within the logic of science have revealed no non-arbitrary way to address the problem of underdetermination as it applies to prediction and thus have failed to account for the preference for prediction over accommodation on logical grounds. Instead, I propose a model (...) that not only justifies and explains this preference, but allows for a richer taxonomy of the types of evidential confirmation that are employed in scientific reasoning. (shrink)

While symbolic colour use has always played a conspicuous role in science research and education, the use of colour in historic diagrams remains a lacuna in the history of science. Investigating the colour use in diagrams often means uncovering a whole cosmology that is not otherwise explicit in the diagram itself. The periodic table is a salient and iconic example of non-mimetic colour use in science. Andreas von Antropoff's (1924) rectangular table of recurrent rainbow colours is famous, as are Alcindo (...) Flores Cabral's (1949) application of colour in his round snail form, using the RGB scheme, and Mazurs's (1967) pine tree system, consisting of warm and cold colours that he attributed to specific groups of elements—an attribution that we can relate back to humoralism and alchemy. From the first periodic tables in the 19th century, individual researchers have used different colour regimes. While standardization may play an obvious role in chemistry and its diagrams, all the more impressive is the anarchistic use of colour in the various diagrams which continue to be created. This article focuses on periodic tables in chemical journals and text books, and explores and compares the development of colour codes found in the few existing polychrome diagrams from the 1920s to the 1970s. (shrink)

The history of the classification of chemical elements is reviewed from the point of view of a bibliophile. The influence that relevant books had on the development of the periodic table and, conversely, how it was incorporated into textbooks, treatises and literary works, with an emphasis on the Spanish bibliography are analyzed in this paper. The reader will also find unexpected connections of the periodic table with the Bible or the architect Buckminster Fuller.

Scientific theories are developed in response to a certain set of phenomena and subsequently evaluated, at least partially, in terms of the quality of fit between those same theories and appropriately distinctive phenomena. To differentiate between these two stages it is popular to describe the former as involving the accommodation of data and the latter as involving the prediction of data. Predictivism is the view that, ceteris paribus, correctly predicting data confers greater confirmation than successfully accommodating data. In this paper, (...) I take issue with a variety of predictivist theses, argue that their role for issues of confirmation is extremely limited, and attempt to account for the appeal that predictivism has enjoyed. Introduction Temporal Predictivism Heuristic Predictivism Weak Predictivism 4.1 Inference to better theories 4.2 Inference to better methods Arguments for Strong Heuristic Predictivism 5.1 Best explanations argument 5.2 Conditional support 5.3 Unique explanations Increased Explanatory Unification 6.1 Explaining what other theories can't 6.2 Contrived hypotheses 6.2 Strength and simplicity Conclusions CiteULike Connotea Del.icio.us What's this? (shrink)

As soon as the SARS‐Cov2 disease was recognized by experts to potentially cause a serious pandemic, a three dimensional diagrammatic image of the virus, colored in strong red, conquered public media globally.This study confronts this iconic virus image with a historic image analysis of 33,000 biomedical articles on coronaviruses published between 1968–2020 and interviews with some of their authors.Only a small fraction of scientific virus publications entail images of the complete virus. Red as an alarm color is not used at (...) all by scientists who don't aim for a non‐scientific public.Circulation in this case concerns the movement of iconic images from a scientific context into a general public. On the basis of hps‐studies on scientific diagrams and especially on color use in scientific diagrams to convey specific messages in public, the paper discusses the role of the claim of public corona‐virus diagram as “scientific.”It points at relevant differences between most frequent scientific corona‐virus images and the diagrammatic image used in public. Both author‐ and readerships (in science and public) follow contrasting aims and values. Thus, the images meet non‐expert readers for whom the images entail very different – and potentially unintended – meanings then to virus experts. (shrink)

Lavoisier defined an element as a chemicalsubstance that cannot be decomposed usingcurrent analytical methods. Mendeleev saw anelement as a substance composed of atoms of thesame atomic weight. These `definitions' doquite different things: Lavoisier'sdistinguishes the elements from the compounds,so that the elements may form the basis of acompositional nomenclature; Mendeleev's offersa criterion of sameness and difference forelemental substances, while Lavoisier's doesnot. In this paper I explore the historical andtheoretical background to each proposal.Lavoisier's and Mendeleev's explicitconceptions of elementhood differed from eachother, and (...) from the official IUPAC definitionof `element' of the 1920s. However, Lavoisierand Mendeleev both subscribed to – andemployed – a deeper notion of a chemicalelement as the component of compound substancesthat (i) can survive chemical change, and (ii)explains the chemical behaviour of itscompounds. (shrink)

The periodic table is one of the best-known systems of classification in science. Because of the information it contains, it raises explanation-seeking questions. Quantum mechanical models of the behaviour of electrons may be seen as providing explanations in response to these questions. In this paper we first address the question ‘Do quantum mechanical models of atoms provide legitimate explanations?’ Because our answer is positive, our next question is ‘Are the explanations provided by quantum mechanical models of atoms mechanistic explanations?’. This (...) question is motivated by the fact that in many scientific disciplines, mechanistic explanations are abundant. Because our answer to the second question is negative, our last question is ‘What kind of explanation do quantum mechanical models of atom provide?’ By addressing these questions, we shed light on the nature of an important type of chemical explanation. (shrink)

Scientific hypotheses may either predict particular unknown facts or accommodate previously-known data. Although affirmed predictions are intuitively more rewarding than accommodations of established facts, opinions divide whether predictive hypotheses are also epistemically superior to accommodation hypotheses. This paper examines the contribution of predictive hypotheses to discoveries of several bio-molecular systems. Having all the necessary elements of the system known beforehand, an abstract predictive hypothesis of semiconservative mode of DNA replication was successfully affirmed. However, in defining the genetic code whose biochemical (...) basis was unclear, hypotheses were only partially effective and supplementary experimentation was required for its conclusive definition. Markedly, hypotheses were entirely inept in predicting workings of complex systems that included unknown elements. Thus, hypotheses did not predict the existence and function of mRNA, the multiple unidentified components of the protein biosynthesis machinery, or the manifold unknown constituents of the ubiquitin–proteasome system of protein breakdown. Consequently, because of their inability to envision unknown entities, predictive hypotheses did not contribute to the elucidation of cation theories remained the sole instrument to explain complex bio-molecular systems, the philosophical question of alleged advantage of predictive over accommodative hypotheses became inconsequential. (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)

This dissertation starts with a concise overview of what philosophers of science have written about unification and its role in scientific explanation during the last 50 years to provide the reader with some background knowledge. In order to bring unification back into the picture, I have followed two strategies, resulting respectively in Parts I and II of this dissertation. In Part I the idea of unification is used to refine and enrich the dominant causalmechanist and causal-interventionist accounts of scientific explanation. (...) In this part of the dissertation I bracket the classical ideas about unification: deduction and derivation. I do grant, for the sake of argument, that explanations are causal and argue that unification is important from within this causalist perspective. In Part II I continue my strategy of digging into scientific practice to find cases of ontological unification. But here I distance myself from the dominant literature that all explanations must be causal. I will investigate whether explanatory unification is possible in non-causal explanations. Part III contains some further reflections and conclusions. I will formulate my primary results, and I will elaborate on their implications for thinking about unification and explanation. The different forms of ontological unification were quite diverse. This relates to the method I have used. Throughout this dissertation the types of unification that were discussed emerged from digging into scientific practice. This philosophy-of-science-practice approach steered me towards a pluralistic view on unification and on explanation. In this dissertation I do not try to develop a new model of explanation and compare it to existing models. The aim is to show that there are important types of explanatory practice which cannot be properly analyzed if we neglect unification as a desideratum for explanations. (shrink)