This paper offers an overview of "the species problem", arguing for a view of species as homeostatic property cluster kinds, positioning the resulting form of realism about species as an alternative to the claim that species are individuals and pluralistic views of species. It draws on taxonomic practice in the neurosciences, especially of neural crest cells and retinal ganglion cells, to motivate both the rejection of the species-as-individuals thesis and species pluralism.

There is no question that the constituents of cells and organisms are joined together by the part-whole relation. Genes are part of cells, and cells are part of organisms. Species taxa, however, have traditionally been conceived of, not as wholes with parts, but as classes with members. But why does the relation change abruptly from part-whole to class-membership above the level of organisms? Ghiselin, Hull and others have argued that it doesn't. Cells and organisms are cohesive mereological sums, and since (...) species taxa are like cells and organisms in the relevant respects, they, too, are cohesive mereological sums. I provide further reasons in support of the thesis that species are mereological sums. I argue, moreover, that the advocate of this thesis is committed to a form of pluralism with respect to the species concept. (shrink)

This paper explains the metaphysical implications of the view that species are individuals (SAI). I first clarify SAI in light of the separate distinctions between individuals and classes, particulars and universals, and abstract and concrete things. I then show why the standard arguments given in defense of SAI are not compelling. Nonetheless, the ontological status of species is linked to the traditional "species problem," in that certain species concepts do entail that species are individuals. I develop the idea that species (...) names are rigid designators and show how this provides additional motivation for SAI. (shrink)

Evolution in its contemporary meaning in biology typically refers to the changes in the proportions of biological types in a population over time (see the entry on the concept of evolution to 1872 for earlier meanings). As evolution is too large of a topic to address thoroughly in one entry, the primary goal of this entry is to serve as a broad overview of contemporary issues in evolution with links to other entries where more in-depth discussion can be found. The (...) entry begins with a brief survey of definitions of evolution, followed by a discussion of the different modes of evolution and related philosophical issues, and ends with a summary of other topics in the philosophy of evolution focusing particularly on topics covered in this encyclopedia. (shrink)

Biology lacks a central organism concept that unambiguously marks the distinction between organism and non-organism because the most important questions about organisms do not depend on this concept. I argue that the two main ways to discover useful biological generalizations about multicellular organization--the study of homology within multicellular lineages and of convergent evolution across lineages in which multicellularity has been independently established--do not require what would have to be a stipulative sharpening of an organism concept.

This paper surveys recent philosophy of biology. It aims to introduce outsiders to the field to the recent literature (which is reviewed in the footnotes) and the main recent debates. I concentrate on three of these: recent critiques of the replicator/vehicle distinction and its application to the idea of the gene as the unit of section; the recent defences of group selection and the idea that standard alternatives to group selection are in fact no more than a disguised form of (...) group selection; and recent ideas on the role of selection in evolution, especially the role of selection in structuring the large-scale history of life. The paper connects philosophy of biology to some more general problems in the philosophy of science, and concludes with a few suggestions about unfinished business. (shrink)

A number of influential biologists are currently pursuing efforts to restore previously extinct species. But for decades, philosophers of biology have regarded “de-extinction” as conceptually incoherent. Once a species is gone, it is gone forever. We argue that a range of metaphysical, biological, and ethical grounds for opposing de-extinction are at best inconclusive and that a pragmatic stance that allows for its possibility is more appealing.

Conceptual change can occur for a variety of reasons; some more scientifically significant than others. The 2006 definition of ‘planet’, which saw Pluto reclassified as a dwarf planet, is an example toward the more mundane end of the scale. I argue however that this case serves as a useful example of a related phenomenon, whereby what appears to be a single kind term conceals two or more distinct concepts with independent scientific utility. I examine the historical background to this case, (...) as a template for developing additional evidence for pluralist approaches to conceptual disputes within science and elsewhere. (shrink)

Species are central to biology, but there is currently no agreement on what the adequate species concept should be, and many have adopted a pluralist stance: different species concepts will be required for different purposes. This thesis is a multidimensional analysis of species pluralism. First I explicate how pluralism differs monism and relativism. I then consider the history of species pluralism. I argue that we must re-frame the species problem, and that re-evaluating Aristotle's role in the histories of systematics can (...) shed light on pluralism. Next I consider different forms of pluralism: evolutionary and extra-evolutionary species pluralism, which differ in their stance on evolutionary theory. I show that pluralism is more than a debate about the species category, but a debate about which concepts are legitimate and a claim about how they interact with one another. Following that, I consider what sort of ontology is required for different forms of species pluralism. I argue that pluralists who deny the unity of biology will require a further plurality of frameworks, while those that ground their pluralism in evolution need only one framework. Finally, I consider what pluralism means for biological practice. I argue that species concepts are tools, and reflect on how pluralism can illuminate the way systematists approach the discovery of new species of yeast. Pluralism can make sense of the way species concepts are used, and can be developed to aid researchers in thinking about how to use the right tools for the right jobs. (shrink)

Philosophy of science is showing an increasing interest in the social aspects and the social organisation of science—the ways social values and social interactions and structures play a role in the creation of knowledge and the ways this role should be taken into account in the organisation of science and science policy. My thesis explores a number of issues related to this theme. I argue that a prominent approach to the social organisation of science—Philip Kitcher’s well-ordered science—runs into a number (...) of problems. They undermine its philosophical plausibility and practical usefulness. I agree with Kitcher that arguments about the social organisation of science should recognise profound societal consequences of science. Kitcher argues that the appropriate organisation of science should therefore take into account laypersons’ values and needs when making decisions concerning research planning, evaluation and application. My criticisms show that this is not enough. Drawing on Helen Longino ideas, I argue that laypersons’ perspectives and knowledge may also be relevant when doing research. In order to show how more inclusive research practices may be possible, I discuss connections between philosophy of science and some developments in science policy, which has also recently shown considerable interest in democratic participation. I demonstrate how public participation experiments in science policy may sometimes be close enough to what the philosopher would recommend. Their analysis can thus be helpful for understanding how societal developments may provide opportunities for the involvement of laypersons in science and what factors may endanger its success. I conclude that a way to pursue a more socially relevant philosophy of science is to focus on the points of contact and possibilities of cooperation between philosophical proposals and these public participation initiatives. (shrink)

'The kind Lion' denotes a kind. Yet many generics are thought to denote kinds also, like the subject-terms in 'The lion has a mane', 'Dinosaurs are extinct', and 'The potato was cultivated in Ireland by the end of the 17th century.' This view may be adequate for the linguist's overall purposes--however, if we limit our attention to the theory of reference, it seems unworkable. The problem is that what is often predicated of kinds is not what is predicated of the (...) lion, dinosaurs, and the potato. Thus, kinds are sometimes said to be abstract objects, immanent universals, nominal essences, etc. But the lion is a predatory cat--it is not an abstract object, nor an immanent universal, nor a nominal essence. I consider several proposals about resolving the dilemma; however, the conclusion is that none of the proposals are adequate. We are thus hard pressed to make sense of allegedly kind-denoting generics, and the lesson is a "Socratic" one about the depths of our ignorance. (shrink)

This chapter contains sections titled: Highlights of Past Literature Current Work Future Work.

In Western common sense, one speaks of there being five human senses, a claim apparently challenged by the biological and psychological sciences. Part of this challenge comes in the form of claiming the existence of additional senses. Part of the challenge comes from positing multiple senses where common sense only speaks of one, such as with the fractionation of “touch” into pressure and temperature senses. One conceptual difficulty in thinking about the number and division of senses is that it's not (...) clear whether the different senses constitute natural kinds and, if not, what kind of kind they are. Should we favor antirealism with respect to the senses, akin to the arguments of some concerning the nature of species or race? I will argue that this first problem is compounded by another: that we ought to be pluralists with respect to the senses—what is meant by the term “sense” varies from context to context, varying even between scientific contexts. (shrink)

In this essay, I begin with an overview of a traditional account of natural kinds, and then consider David Hull's critique of species as natural kinds and the associated notion of human nature. Second, I explore recent "liberal" accounts of human nature provided by Edouard Machery and Grant Ramsey and criticized by Tim Lewens. They attempt to avoid the criticisms of- fered by Hull. After examining those views, I turn to Richard Boyd's Homeostatic Property Cluster account of natural kinds which (...) is flexible but detailed enough to avoid Hull's criticisms but also those affecting the more recent views. We then consider what I call the "problem of variation." Fourth, I consider two case studies -- the basic emotions and facial expressions and inbreeding avoidance and incest taboos. I argue that the former is a component of a Boydian human nature but the latter is not. The conclusion is that if there is a human nature, it must be argued for on a case-by-case basis. And, one of most discussed cases thought to be part of our nature is simply not. (shrink)

The thesis that species are individuals, and not classes as the traditional view had it, has been influential in the last 25 years. In this paper David Hull's arguments for the thesis are surveyed, as well as some counterarguments presented by Philip Kitcher. It is claimed that though species can be conceptualized as individuals, we are not compelled to view them in that way. The importance of the issue seems to have been somewhat exaggerated. However, it might happen that empirical (...) findings concerning species selection would strengthen the case for the thesis, thereby rendering it straightforwardly empirical. The applicability of teleological explanation is suggested as a criterion for biological individuality. (shrink)

The paper comments and elaborates upon five pages of P. F. Strawson’s Individuals , together with his ‘Entity and Identity’ and ‘Universals’. The focus is on Strawson’s understanding of individual non-particulars as types or universals, and on his contention that the most obvious non-particular entities are the broadly conceived artefacts including the works of art. The narrow focus is on the implications of Strawson’s suggestion that ‘an appropriate model for non-particulars of these kinds is that of a model particular - (...) a kind of prototype, or ideal example, itself particular, which serves as a rule or standard for the production of others’ . The paper analyzes the relation between Strawson’s position and the issue of artefacts and their ontology. It also asks about some less obvious affinities between the problem of the non-particulars and Strawson’s concept of a person. (shrink)

The longstanding species problem in biology has a history that suggests a solution, and that history is not the received history found in many texts written by biologists or philosophers. The notion of species as the division into subordinate groups of any generic predicate was the staple of logic from Aristotle through the middle ages until quite recently. However, the biological species concept during the same period was at first subtly and then overtly different. Unlike the logic sense, which relied (...) on definitions of the essence of both genus and species, biological species from the time of Epicurus were consistently considered to involve a reproductive element: in short, living species relied not on essential definitions, but on the generative cause, which might not be definable. I term this the generative conception of species: species were the generation by reproduction of form. This undercuts the claim that species before Darwin were essentialist, and divorces the notion of a type from that of essence. In fact, as late as the end of the nineteenth century, logicians explicitly treated biological “species” as a homonym only of logical essentialist species, and permitted considerable deviation from the type or form. At every point, species in logic were thought to be a subset, in effect, of some more general notion. I sketch a history of both philosophical and biological traditions of the species concept, before turning to the current conceptions. These are reconsidered in the light of this history, and in particular Mayr’s changing views are shown to be somewhat Whiggish, historiographically. Of the many touted biological species concepts, only one of which (Mayr’s) is called _the_ Biological Species Concept, none appears to capture all the relevant facts, intuitions, and operational requirements of biology. Cladistic conceptions, however, have much in common with the older philosophical literature, in that the natural group of cladism is the clade, or monophyletic group. After considering the Individuality Thesis, and the metaphysics of species, we see that species are the most particular terminal taxa in a clade, and that they are “defined” in terms of the particular synapomorphies, or evolved characters, that are causally responsible for keeping the lineages that organisms form distinct from one another. In this way, we can remain within the generative conception of species that has been in play for over two millennia, and yet avoid the pitfalls of prior attempts to find a universal conception of species. (shrink)

In Science, Truth, and Democracy (2001a), Kitcher moderates the strongest ontological realist thesis he defended in The Advancement of Science (1993a), with the aim of making compatible the correspondence theory of truth with conceptual relativity. However, it is not clear that both things could be harmonized. If our knowledge of the world is mediated by our categories and concepts; if the selection of these categories and concepts may vary according to our interests, and they are not the consequence of the (...) existence of certain supposed natural kinds or some intrinsic structure of the world, it is very problematic to establish what our true statements correspond to. This paper analyzes the transformation in Kitcher's realism and expounds the main difficulties in this project. Finally, a modality of moderate ontological realism will be proposed that, despite of keeping the sprit of the conceptual relativity, is strong enough to support the correspondence theory of truth. (shrink)

Species serve as both the basic units of macroevolutionary studies and as the basic units of taxonomic classification. In this paper I argue that the taxa identified as species by the Phylogenetic Species Concept (Mishler and Brandon 1987) are the units of biological organization most causally relevant to the evolutionary process but that such units exist at multiple levels within the hierarchy of any phylogenetic lineage. The PSC gives us no way of identifying one of these levels as the privileged (...) level on which taxonomic classifications can be based. (shrink)