In his Treatise of Human Nature, David Hume asked how people succeed in constructing edifices of belief from their limited store of sensory impressions and derived ideas. Hume could adduce no evidence to support the existence of an inner self that intelligently manipulates impressions and ideas. At the same time, he recognized in himself the conviction that there is inner self. Today, there is a growing conviction among cognitive neuro-scientists, behavioral scientists, science journalists, and their publics that neuroscience is on (...) the verge of providing us with the ultimate solution to ‘‘Hume’s problem.’’ This article describes two approaches to this solution. (shrink)

The cell theory—the thesis that all life is made up of one or more cells, the fundamental structural and physiological unit—is one of the most celebrated achievements of modern biological science. And yet from its very inception in the nineteenth century it has faced repeated criticism from some biologists. Why do some continue to criticize the cell theory, and how has it managed nevertheless to keep burying its undertakers? The answers to these questions reveal the complex nature of the cell (...) theory and the cell concept on which it is based. Like other scientific ‘laws’, the assertion that all living things are made of cells purchases its universality at the expense of abstraction. If, however, this law is regarded merely as a widely applicable empirical generalization with notable exceptions, it still remains too important to discard. Debate about whether the cell or the organism standpoint provides the more correct account of anatomical, physiological, and developmental facts illustrates the tension between our attempts to express the truth about reality in conceptual terms conducive to a unified human understanding. (shrink)

In the nineteenth century protozoology and early cell biology intersected through the nexus of Darwin's theory of evolution. As single-celled organisms, amoebae offered an attractive focus of study for researchers seeking evolutionary relationships between the cells of humans and other animals, and their primitive appearance made them a favourite model for the ancient ancestor of all living things. Their resemblance to human and other metazoan cells made them popular objects of study among morphologists, physiologists, and even those investigating animal behaviour. (...) The amoeba became the exemplar of the new protoplasmic cell concept of mid-century and because its apparent simplicity made it widely generalizable it became a popular subject in a breadth of experimental investigations and theoretical speculations. It was able to do this because "the amoeba" denotes not a particular organism, but a general type of behaviour common to the cells of a range of protozoa, simple plants and higher animals. Its status as an exemplary cell also rested upon auxiliary philosophical assumptions about what constitutes a primitive characteristic and the thesis that evolution is a progressive development of order from chaos. (shrink)

Although the cell is commonly addressed as the unit of life, historians and philosophers have devoted relatively little attention to this concept in comparison to other fundamental concepts of biology such as the gene or species. As a partial remedy to this neglect, we introduce the cell as a major point of connection between various disciplinary approaches, epistemic strategies, technological vectors and overarching biological processes such as metabolism, growth, reproduction and evolution. We suggest that the role of the cell as (...) a nexus forms the basis for a new philosophical and historical appreciation of cell biology. This perspective focuses less on the cell as a well-defined, stable object and places more emphasis on its role as a mediator of fundamental biological processes. (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)

Biological atomism postulates that all life is composed of elementary and indivisible vital units. The activity of a living organism is thus conceived as the result of the activities and interactions of its elementary constituents, each of which individually already exhibits all the attributes proper to life. This paper surveys some of the key episodes in the history of biological atomism, and situates cell theory within this tradition. The atomistic foundations of cell theory are subsequently dissected and discussed, together with (...) the theory’s conceptual development and eventual consolidation. This paper then examines the major criticisms that have been waged against cell theory, and argues that these too can be interpreted through the prism of biological atomism as attempts to relocate the true biological atom away from the cell to a level of organization above or below it. Overall, biological atomism provides a useful perspective through which to examine the history and philosophy of cell theory, and it also opens up a new way of thinking about the epistemic decomposition of living organisms that significantly departs from the physicochemical reductionism of mechanistic biology. (shrink)

In 1877, the young Alfred Espinas defended a philosophical study, ‘doctorat ès lettres’, at the Sorbonne University, entitled Des Sociétés animales. This was to become one of the principal sources of French organicist sociology. The paradox, however, is that this work seems to be fundamentally a study of natural science. Espinas tried to justify his position theoretically through two types of reciprocally exclusive and uncomplementary arguments. The first one consists in showing that only certain kinds of animal groupings belong legitimately, (...) if not academically, to sociology. The second one has a greater audacious and uncontrollable dimension. It consists in asserting that all pluricellular organisms are true societies. In this article we first focus on the role played by cellular theory in such a ‘sociologization’ of biology, concerning the extension of sociology. Second, we examine the importance of such confusion within the fields of extension, in aiming to explain the conceptual transfers between social sciences and life sciences, in the second half of the 19th century. (shrink)

La division du travail physiologique est un concept tombé en désuétude en biologie. Quand l’expression est employée, c’est sans égard pour sa fonction nomologique importante dans la biologie du second xixe. Nous analyserons l’importation de la division du travail de l’économie à la biologie, malgré les difficultés de validation que posait son transfert d’une science à l’autre. La notion a ainsi continué sa carrière dans une biologie gagnée à la théorie cellulaire, cependant que ses déterminations économiques perdaient leur pertinence. Nous (...) terminerons en interrogeant sa disparition au début du xxe. La division du travail physiologique, une fois purifiée de son économicité primitive, ne pouvait sans doute que retourner à un stade métaphorique. (shrink)