This article characterizes various species concepts in terms of set-theoretic models that license biological inferences and illustrates the logical connections among different species concepts. Species in this construal are abstract models, rather than biological or even tangible entities, and relate to individual organisms via representation, rather than the membership or mereological whole/part relationship. The proposal sheds new light on vexed issues of species and situates them within broader philosophical contexts of model selection, scientific representation, and scientific realism.

Four ordering systems have been used most frequently in taxonomy: (1) special purpose classifications, (2) downward classifications (identification schemes), (3) upward or grouping classifications (traditional), and (4) Hennigian phylogenetic systems. The special properties of these four systems are critically evaluated. Grouping classifications and phylogenetic systems have very different objectives: the former the documentation of similarity and closeness of relationship, the latter of phylogeny. Both are legitimate ordering systems.

The pheneticist philosophy holds that biological taxa are clusters of entities united by a form of all-things-considered resemblance. This view of taxonomy has come in for almost universal criticism from philosophers, and has received little praise from biologists, over the past 30 years or so. This article defends a modest pheneticism, understood as part of a pluralist view of taxonomy. First, phenetic approaches to taxonomy are alive and well in biological practice, especially in the areas of microbiology and botany. Second, (...) the pheneticist notion of overall similarity is defensible, and is implicitly endorsed even by those (such as Quine) usually implicated in attacks on similarity. Third, there are limited biological domains within which pheneticism’s conception of species as kinds (rather than heterogeneous individuals) remains applicable. (shrink)

This study will focus on the differences in the way that Roman Paganism and Christianity organize systems of beliefs. It rejects the theory that “beliefs” have no place in the Roman religion, but stresses the differences between Christian orthodoxy, in which mandatory dogmas define group identity, and the essentially polythetic nature of Roman religious organization, in which incompatible beliefs could exist simultaneously in the community without conflict. In explaining how such beliefs could coexist in Rome, the study emphasizes three main (...) conceptual mechanisms: polymorphism, the idea that gods could have multiple identities with incompatible attributes, orthopraxy, the focus upon standardized ritual rather than standardized belief, and pietas, the Roman ideal of reciprocal obligation, which was flexible enough to allow Romans to maintain relationships simultaneously with multiple gods at varying levels of personal commitment. (shrink)

Despite several decades of criticism, dichotomous thinking about behavioral development remains widespread and influential. This is particularly true in study of birdsong development, where it has become increasingly common to diagnose songs, elements of songs, or precursors of songs as either innate or learned on the basis of isolation-rearing experiments. The theory of sensory templates has encouraged both the dichotomous approach and an emphasis on structural rather than functional aspects of song development. As a result, potentially important lines of investigation (...) have been overlooked and the interpretation of existing data is often flawed. Evidence for a genetic origin of behavioraldifferencesis frequently interpreted as evidence for the genetic determination of behavioralcharacters. The technique of isolation rearing remains the methodology of choice for many investigators, despite the fact that it offers only a rather crude analysis of the contribution of experience to song development and provides no information at all about genetic contributions to development. The latter could in principle be elucidated by the application of developmental-genetic techniques, but it is unlikely that these can easily be applied to the study of birdsong. Because developmental questions are so often posed in terms of the learned–innate dichotomy, “experience” is taken to be synonymous with “learning” and the possible role of nonobvious contributions to song development has largely been ignored. An alternative approach, based on Daniel Lehrman's interactionist theory of development, permits a more thorough appreciation of the problems that have yet to be addressed, and provides a more secure conceptual foundation for theories of song development. (shrink)

The twentieth century witnessed a dramatic increase in the use of statistics by biologists, including systematists. The modern synthesis and new systematics stimulated this development, particularly after World War II. The rise of "the statistical frame of mind " resulted in a rethinking of the relationship between biological and mathematical points of view, the roles of objectivity and subjectivity in systematic research, the implications of new computing technologies, and the place of systematics among the biological disciplines.

I spell out and update the individuality thesis, that species are individuals, and not classes, sets, or kinds. I offer three complementary presentations of this thesis. First, as a way of resolving an inconsistent triad about natural kinds; second, as a phylogenetic systematics theoretical perspective; and, finally, as a novel recursive account of an evolved character. These approaches do different sorts of work, serving different interests. Presenting them together produces a taxonomy of the debates over the thesis, and isolates ways (...) it has been productive. This goes to the larger point of this paper: a defense of the individuality thesis in terms of its utility, and an update of it in light of recent theoretical developments and empirical work in biology. (shrink)

Three competing ‘methods’ have been endorsed for inferring phylogenetic hypotheses: parsimony, likelihood, and Bayesianism. The latter two have been claimed superior because they take into account rates of sequence substitution. Can rates of substitution be justified on its own accord in inferences of explanatory hypotheses? Answering this question requires addressing four issues: (1) the aim of scientific inquiry, (2) the nature of why-questions, (3) explanatory hypotheses as answers to why-questions, and (4) acknowledging that neither parsimony, likelihood, nor Bayesianism are inferential (...) actions leading to explanatory hypotheses. The aim of scientific inquiry is to acquire causal understanding of effects. Observation statements of organismal characters lead to implicit or explicit why-questions. Those questions, conveyed in data matrices, assume the truth of observation statements, which is contrary to subsequently invoking substitution rates within inferences to phylogenetic hypotheses. Inferences of explanatory hypotheses are abductive in form, such that some version of an evolutionary theory(ies) is/are included or implied. If rates of sequence evolution are to be considered, it must be done prior to, rather than within abduction, which requires renaming those putatively-shared nucleotides subject to substitution rates. There are, however, no epistemic grounds for renaming characters to accommodate rates, calling into question the legitimacy of causally accounting for sequence data. (shrink)

Our understanding of the sense of taste is largely based on research designed and interpreted in terms of the traditional four tastes: sweet, sour, salty, and bitter, and now a few more. This concept of basic tastes has no rational definition to test, and thus it has not been tested. As a demonstration, a preliminary attempt to test one common but arbitrary psychophysical definition of basic tastes is included in this article; that the basic tastes are unique in being able (...) to account for other tastes. This definition was falsified in that other stimuli do about as well as the basic words and stimuli. To the extent that this finding might show analogies with other studies of receptor, neural, and psychophysical phenomena, the validity of the century-long literature of the science of taste based on a few is called into question. The possible origins, meaning, and influence of this concept are discussed. Tests of the model with control studies are suggested in all areas of taste related to basic tastes. As a stronger alternative to the basic tradition, the advantages of the across-fiber pattern model are discussed; it is based on a rational data-based hypothesis, and has survived attempts at falsification. Such has found broad acceptance in many neural systems. (shrink)

One general principle in the construction of classification schemes is that of grouping phenomena to be classified according to their shared origin in evolution or history (phylogenesis). In general schemes, this idea has been applied by several classificationists in identifying a series of integrative levels, each originated from the previous ones, and using them as the main classes. In special schemes, common origin is a key principle in many domains: examples are given from the classification of climates, of organisms, and (...) of musical instruments. Experience from these domains, however, suggests that using common origin alone, as done in cladistic taxonomy, can produce weird results, like having birds as a subclass of reptiles; while the most satisfying classifications use a well balanced mix of common origin and similarity. It is discussed how this could be applied to the development of a general classification of phenomena in an emergentist perspective, and how the resulting classification tree could be structured. Charles Bennett's notion of logical depth appears to be a promising conceptual tool for this purpose. (shrink)

In this article, I reconsider bio-essentialism in the study of kinship, centering on David Schneider’s influential critique that concluded that kinship was “a non-subject” (1972:51). Schneider’s critique is often taken to have shown the limitations of and problems with past views of kinship based on biology, genealogy, and reproduction, a critique that subsequently led those reworking kinship as relatedness in the new kinship studies to view their enterprise as divorced from such bio-essentialist studies. Beginning with an alternative narrative connecting kinship (...) past and present and concluding by introducing a novel way of thinking about kinship, I have three constituent aims in this research article: (1) to reconceptualize the relationship between kinship past and kinship present; (2) to reevaluate Schneider’s critique of bio-essentialism and what this implies for the contemporary study of kinship; and (3) subsequently to redirect theoretical discussion of what kinship is. This concluding discussion introduces a general view, the homeostatic property cluster (HPC) view of kinds, into anthropology, providing a theoretical framework that facilitates realization of the often-touted desideratum of the integration of biological and social features of kinship. [bio-essentialism, kinship studies, homeostatic property cluster kinds, Schneider, genealogy]. (shrink)

The theory of concepts advanced in the dissertation aims at accounting for a) how a concept makes successful practice possible, and b) how a scientific concept can be subject to rational change in the course of history. Traditional accounts in the philosophy of science have usually studied concepts in terms only of their reference; their concern is to establish a stability of reference in order to address the incommensurability problem. My discussion, in contrast, suggests that each scientific concept consists of (...) three components of content: 1) reference, 2) inferential role, and 3) the epistemic goal pursued with the concept's use. I argue that in the course of history a concept can change in any of these three components, and that change in one component—including change of reference—can be accounted for as being rational relative to other components, in particular a concept's epistemic goal.This semantic framework is applied to two cases from the history of biology: the homology concept as used in 19th and 20th century biology, and the gene concept as used in different parts of the 20th century. The homology case study argues that the advent of Darwinian evolutionary theory, despite introducing a new definition of homology, did not bring about a new homology concept (distinct from the pre-Darwinian concept) in the 19th century. Nowadays, however, distinct homology concepts are used in systematics/evolutionary biology, in evolutionary developmental biology, and in molecular biology. The emergence of these different homology concepts is explained as occurring in a rational fashion. The gene case study argues that conceptual progress occurred with the transition from the classical to the molecular gene concept, despite a change in reference. In the last two decades, change occurred internal to the molecular gene concept, so that nowadays this concept's usage and reference varies from context to context. I argue that this situation emerged rationally and that the current variation in usage and reference is conducive to biological practice.The dissertation uses ideas and methodological tools from the philosophy of mind and language, the philosophy of science, the history of science, and the psychology of concepts. (shrink)