The current widespread belief that taxonomic methods used before Darwin were essentialist is ill-founded. The essentialist method developed by followers of Plato and Aristotle required definitions to state properties that are always present. Polythetic groups do not obey that requirement, whatever may have been the ontological beliefs of the taxonomist recognizing such groups. Two distinct methods of forming higher taxa, by chaining and by examplar, were widely used in the period between Linnaeus and Darwin, and both generated polythetic groups. Philosopher (...) William Whewell congratulated pre-Darwinian taxonomists for not adhering to the rigid ideal of definition used in the mathematical sciences. What he called the method of types is here called the method of exemplars because typology has been equated with essentialism, whereas the use of a type species as the reference point or prototype for a higher category was a practice inconsistent with essentialism. The story that the essentialism of philosophers dominated the development of systematics may prove to be a myth. (shrink)

The vision of natural kinds that is most common in the modern philosophy of biology, particularly with respect to the question whether species and other taxa are natural kinds, is based on a revision of the notion by Mill in A System of Logic. However, there was another conception that Whewell had previously captured well, which taxonomists have always employed, of kinds as being types that need not have necessary and sufficient characters and properties, or essences. These competing views employ (...) different approaches to scientific methodologies: Mill’s class-kinds are not formed by induction but by deduction, while Whewell’s type-kinds are inductive. More recently, phylogenetic kinds (clades, or monophyletic-kinds) are inductively projectible, and escape Mill’s strictures. Mill’s version represents a shift in the notions of kinds from the biological to the physical sciences. (shrink)

Nineteenth-century British entomologist William Kirby is best known for his generic division of bees based on tongues and his vigorous defence of natural theology. Focusing on these aspects of Kirby's work has lead many current scholars to characterise Kirby as an "essentialist." As a result of this characterisation, many important aspects of his work, Monographia Apum Angliœ (1802) have been over-looked or misunderstood. Kirby's religious devotion, for example, have lead some scholars to assume Kirby used the term "type" for connecting (...) an ontological assumption about essences with a creationist assumption about species fixity, which I argue conceals a variety of ways Kirby employed the term. Also, Kirby frequently cautioned against organising a classification system exclusively by what he called "analytic reasoning," a style of reasoning 20th century scholars often associate with Aristotelian logic of division. I argue that Kirby's critique of analytic reasoning brought the virtues of his own methodological agenda into sharp relief. Kirby used familiar metaphors in the natural history literature-Ariadne's thread, the Eleusinian mysteries, and Bacon's bee and spider metaphors-to emphasise the virtues of building tradition and cooperation in the goals and methodological practices of 19th century British naturalists. (shrink)

Mary Winsor (2003) argues against the received view that pre-Darwinian taxonomy was characterized mainly by essentialism. She argues, instead, that the methods of pre-Darwinian taxonomists, in spite of whatever their beliefs, were that of clusterists, so that the received view, propagated mainly by certain modern biologists and philosophers of biology, should at last be put to rest as a myth. I argue that shes right when it comes to higher taxa, but wrong when it comes the most important category of (...) all, the species category. (shrink)

Historians and philosophers of science have interpreted the taxonomic theory of Carl Linnaeus as an ‘essentialist’, ‘Aristotelian’, or even ‘scholastic’ one. This interpretation is flatly contradicted by what Linnaeus himself had to say about taxonomy in Systema naturae , Fundamenta botanica and Genera plantarum . This paper straightens out some of the more basic misinterpretations by showing that: Linnaeus’s species concept took account of reproductive relations among organisms and was therefore not metaphysical, but biological; Linnaeus did not favour classification by (...) logical division, but criticized it for necessarily failing to represent what he called ‘natural’ genera; Linnaeus’s definitions of ‘natural’ genera and species were not essentialist, but descriptive and polytypic; Linnaeus’s method in establishing ‘natural’ definitions was not deductive, but consisted in an inductive, bottom-up procedure of comparing concrete specimens. The conclusion will discuss the fragmentary and provisional nature of Linnaeus’s ‘natural method’. I will argue in particular that Linnaeus opted for inductive strategies not on abstract epistemological grounds, but in order to confer stability and continuity to the explorative practices of contemporary natural history. (shrink)

Rudolf Leuckart's 1851 pamphlet Ueber den Polymorphismus der Individuen (On the polymorphism of individuals) stood at the heart of naturalists' discussions on biological individuals, parts and wholes in mid-nineteenth-century Britain and Europe. Our analysis, which accompanies the first translation of this pamphlet into English, situates Leuckart's contribution to these discussions in two ways. First, we present it as part of a complex conceptual knot involving not only individuality and the understanding of compound organisms, but also the alternation of generations, the (...) division of labor in nature, and the possibility of finding general laws of the organic world. Leuckart's pamphlet is important as a novel attempt to give order to the strands of this knot. It also solved a set of key biological problems in a way that avoided some of the drawbacks of an earlier teleological tradition. Second, we situate the pamphlet within a longer trajectory of inquiry into part-whole relations in biology from the mid-eighteenth century to the present. We argue that biological individuality, along with the problem-complexes with which it engaged, was as central a problem to naturalists before 1859 as evolution, and that Leuckart's contributions to it left a long legacy that persisted well into the twentieth century. As biologists' interests in part-whole relations are once again on the upswing, the longue durée of this problem merits renewed consideration. (shrink)

Rudolf Leuckart’s 1851 pamphlet Ueber den Polymorphismus der Individuen stood at the heart of naturalists’ discussions on biological individuals, parts and wholes in mid-nineteenth-century Britain and Europe. Our analysis, which accompanies the first translation of this pamphlet into English, situates Leuckart’s contribution to these discussions in two ways. First, we present it as part of a complex conceptual knot involving not only individuality and the understanding of compound organisms, but also the alternation of generations, the division of labor in nature, (...) and the possibility of finding general laws of the organic world. Leuckart’s pamphlet is important as a novel attempt to give order to the strands of this knot. It also solved a set of key biological problems in a way that avoided some of the drawbacks of an earlier teleological tradition. Second, we situate the pamphlet within a longer trajectory of inquiry into part-whole relations in biology from the mid-eighteenth century to the present. We argue that biological individuality, along with the problem-complexes with which it engaged, was as central a problem to naturalists before 1859 as evolution, and that Leuckart’s contributions to it left a long legacy that persisted well into the twentieth century. As biologists’ interests in part-whole relations are once again on the upswing, the longue durée of this problem merits renewed consideration. (shrink)

William Sharp Macleay developed the quinarian system of classification in his Horæ Entomologicæ, published in two parts in 1819 and 1821. For two decades, the quinarian system was widely discussed in Britain and influenced such naturalists as Charles Darwin, Richard Owen, and Thomas Huxley. This paper offers the first detailed account of Macleay’s development of the quinarian system. Macleay developed his system under the shaping influence of two pressures: (1) the insistence by followers of Linnaeus on developing artificial systems at (...) the expense of the natural system and (2) the apparent tension between the continuity of organic nature and the failure of linear classification schemes (which continuity seemed to require). Against what he perceived as dogmatic indolence on the part of the Linnaeans, Macleay developed a philosophy of science in which hypotheses that exceeded the available evidence should be proposed and subjected to severe tests. He also developed a novel comparative anatomical methodology, the method of variation, to aid in his search for the natural system. Using this method, he developed an intricate system that showed how organic nature could be continuous without being linear. A failure to appreciate these facets of Macleay’s thought has led to several misunderstandings of him and his work, most notably that he was an idealist. These misunderstandings are here rebutted. (shrink)

By following the arguments between Coenraad J. Temminck and fellow ornithologists Louis J.-P. Vieillot and Nicholas Vigors, this paper sketches, to a degree, the state of zoological classification and nomenclature between 1825 and 1840 in Europe. The discussions revolved around the problems caused by an unstable nomenclature, the different definitions of genera and species and the best method to achieve a natural system of classification. As more and more naturalists concerned with classifying and arranging the groups of birds joined these (...) discussions, a broad platform for debate emerged around the 1840s that gave a major impulse to the disciplines of taxonomy and systematics. Natural history ceased to be dominated by a few influential scientific authorities and became the scientific field where debate preceded agreement and, with it, progress. With this ‘democratization’ of natural history, Temminck's status significantly changed between 1815 and 1840. After that year, his own views on classification along with certain economical and political developments in The Netherlands led Temminck to abandon the arena of ornithology and therefore, to lose his scientific authority. (shrink)

Historians and philosophers of science agree that Darwin had an understanding of species which led to a workable theory of their origins. To Darwin species did not differ essentially from ‘varieties’ within species, but were distinguishable in that they had developed gaps in formerly continuous morphological variation. Similar ideas can be defended today after updating them with modern population genetics. Why then, in the 1930s and 1940s, did Dobzhansky, Mayr and others argue that Darwin failed to understand species and speciation? (...) Mayr and Dobzhansky argued that reproductively isolated species were more distinct and ‘real’ than Darwin had proposed. Believing species to be inherently cohesive, Mayr inferred that speciation normally required geographic isolation, an argument that he believed, incorrectly, Darwin had failed to appreciate. Also, before the sociobiology revolution of the 1960s and 1970s, biologists often argued that traits beneficial to whole populations would spread. Reproductive isolation was thus seen as an adaptive trait to prevent disintegration of species. Finally, molecular genetic markers did not exist, and so a presumed biological function of species, reproductive isolation, seemed to delimit cryptic species better than character-based criteria like Darwin’s. Today, abundant genetic markers are available and widely used to delimit species, for example using assignment tests: genetics has replaced a Darwinian reliance on morphology for detecting gaps between species. In the 150th anniversary of The Origin of Species , we appear to be returning to more Darwinian views on species, and to a fuller appreciation of what Darwin meant. (shrink)

There is a pervasive contrast in the early natural history writings of the co-discoverers of natural selection, Alfred Russel Wallace and Charles Darwin. In his writings from South America and the Malay Archipelago (1848-1852, 1854-1862). Wallace consistently emphasized species and genera, and separated these descriptions from his rarer and briefer discussions of individual organisms. In contrast, Darwin's writings during the Beagle voyage (1831-1836) emphasized individual organisms, and mingled descriptions of individuals and groups. The contrast is explained by the different practices (...) of the two naturalists in the field. Wallace and Darwin went to the field with different educational experiences and social connections, constrained by different responsibilities and theoretical interests. These in turn resulted in different natural history practices; i.e., different habits and working routines in the field. Wallace's intense collecting activities aimed at a complete inventory of different species and their distributions at many localities. Darwin's less intense collecting practice focused on detailed observations of individual organisms. These different practices resulted in different material, textual and conceptual products. Placing natural history practices at the center of analysis reveals connections among these diverse products, and throws light on Wallace and Darwin's respective treatment of individuals and groups in natural history. In particular, this approach clarifies the relation between individuals and groups in Wallace's theory of natural selection, and provides an integrative starting point for further investigations of the broader social factors that shaped Victorian natural history practices and their scientific products. (shrink)

By following the arguments between Coenraad J. Temminck and fellow ornithologists Louis J.-P. Vieillot and Nicholas Vigors, this paper sketches, to a degree, the state of zoological classification and nomenclature between 1825 and 1840 in Europe. The discussions revolved around the problems caused by an unstable nomenclature, the different definitions of genera and species and the best method to achieve a natural system of classification. As more and more naturalists concerned with classifying and arranging the groups of birds joined these (...) discussions, a broad platform for debate emerged around the 1840s that gave a major impulse to the disciplines of taxonomy and systematics. Natural history ceased to be dominated by a few influential scientific authorities and became the scientific field where debate preceded agreement and, with it, progress. With this ‘democratization’ of natural history, Temminck’s status significantly changed between 1815 and 1840. After that year, his own views on classification along with certain economical and political developments in The Netherlands led Temminck to abandon the arena of ornithology and therefore, to lose his scientific authority. (shrink)

TheCatalogue of Scientific Papers, published by the Royal Society of London beginning in 1867, projected back to the beginning of the nineteenth century a novel vision of the history of science in which knowledge was built up out of discrete papers each connected to an author. Its construction was an act of canon formation that helped naturalize the idea that scientific publishing consisted of special kinds of texts and authors that were set apart from the wider landscape of publishing. By (...) recovering the decisions and struggles through which theCataloguewas assembled, this essay aims to contribute to current efforts to denaturalize the scientific paper as the dominant genre of scientific life. By privileging a specific representation of the course of a scientific life as a list of papers, theCataloguehelped shape underlying assumptions about the most valuable fruits of a scientific career. Its enumerated lists of authors’ periodical publications were quickly put to use as a means of measuring scientific productivity and reputation, as well as by writers of biography and history. Although it was first conceived as a search technology, this essay locates theCatalogue’s most consequential legacy in its uses as a technology of valuation. (shrink)