Online research in philosophy

The aim of this paper is to evaluate etiological accounts of functions for the domain of technical artefacts. Etiological theories ascribe functions to items on the basis of the causal histories of those items; they apply relatively straightforwardly to the biological domain, in which neo-Darwinian evolutionary theory provides a well-developed and generally accepted background for describing the causal histories of biological items. Yet there is no well-developed and generally accepted theory for describing the causal history of artefacts, so the application of etiological theories to the technical domain is hardly straightforward. In this paper we consider the transposition of etiological theories in general from the biological to the technical domain. We argue that a number of etiological theories that appear defensible for biology become untenable for technology. We illustrate our argument by showing that the standard etiological accounts of Neander and Millikan, and some recent attempts to improve on them, provide examples of such untenable theories. 1 Introduction 2 Desiderata for theories of functions 3 Etiological theories in general 3.1 Common core and divergent aims 3.2 Reproduction versus non-reproduction etiological theories 3.3 Intentionalist versus non-intentionalist etiological theories 4 Problems for etiological theories in the technical domain 5 The failure of existing reproduction theories 6 The failure of existing non-reproduction theories 7 Improving reproduction by hybridisation 8 Conclusions.

The account of nature and humanity’s relationship to nature are of central importance for bioethics. The Scientific Revolution was a critical development in the history of this question and many contemporary accounts of nature find their beginnings here. While the innovative approach to nature going out of the seventeenth century was reliant upon accounts of nature from the early modern period, the Middle Ages, late-antiquity and antiquity, it also parted ways with some of the understandings of nature from these epochs. Here I analyze this development and suggests that some of the insights from older understandings of nature may be helpful for bioethics today, even if there can be no simple return to them.

Wilkinson (1991a) developed arguments that the distributions of primitive character states may delimit clades, and proposed a method that exploited the evidence of primitive character state distributions for inferring clades. Whiting and Kelly (1995) presented a critique of these ideas, arguing that they are logically incoherent and that the method does not succeed in its aims. This critique severely misrepresents the original arguments and the method, and amounts to no more than an attack on a straw man.

Although naming biological clades is a major activity in taxonomy, little attention has been paid to what these names actually refer to. In philosophy, definite descriptions have long been considered equivalent to the meaning of names and biological taxonomy is a scientific application of these ideas. One problem with definite descriptions as the meanings of names is that the name will refer to whatever fits the description rather than the intended individual (clade). Recent proposals for explicit phylogenetic definitions of clade names suffer from similar problems and we argue that clade names cannot be defined since they lack intension. Furthermore we stress the importance of tree-thinking for phylogenetic reference to work properly.

The biological species (biospecies) concept applies only to sexually reproducing species, which means that until sexual reproduction evolved, there were no biospecies. On the universal tree of life, biospecies concepts therefore apply only to a relatively small number of clades, notably plants andanimals. I argue that it is useful to treat the various ways of being a species (species modes) as traits of clades. By extension from biospecies to the other concepts intended to capture the natural realities of what keeps taxa distinct, we can treat other modes as traits also, and so come to understand that theplurality of species concepts reflects the biological realities of monophyletic groups.We should expect that specialists in different organisms will tend to favour those concepts that best represent the intrinsic mechanisms that keep taxa distinct in their clades. I will address the question whether modes ofreproduction such as asexual and sexual reproduction are natural classes, given that they are paraphyletic in most clades.

The idea that clades might be units of selection, defended by a number of biologists and philosophers of biology, is critically examined. I argue that only entities which reproduce, i.e. leave offspring, can be units of selection, and that a necessary condition of reproduction is that the offspring entity be able, in principle, to outlive its parental entity. Given that clades are monophlyetic by definition, it follows that clades do not reproduce, so it makes no sense to talk about a clade's fitness, so clade selection is impossible. Three possible responses to this argument are examined and found wanting.

Samir Okasha argues that clade selection is an incoherent concept, because the relation that constitutes clades is such that it renders parent-offspring (reproduction) relations between clades impossible. He reasons that since clades cannot reproduce, it is not coherent to speak of natural selection operating at the clade level. We argue, however, that when species-level lineages and clade-level lineages are treated consistently according to standard cladist commitments, clade reproduction is indeed possible and clade selection is coherent if certain conditions obtain. Despite clade selection’s logical coherence, however, we share some of Okasha’s pessimism. Whether or not clades are a unit of selection is ultimately a question of empirical support and theoretical import, but we offer reasons to be skeptical about clade selection as a research programme.

Samir Okasha argues that clade selection is an incoherent concept, because the relation that constitutes clades is such that it renders parent-offspring (reproduction) relations between clades impossible. He reasons that since clades cannot reproduce, it is not coherent to speak of natural selection operating at the clade level. We argue, however, that when species-level lineages and clade-level lineages are treated consistently according to standard cladist commitments, clade reproduction is indeed possible and clade selection is coherent if certain conditions obtain. Despite clade selection's logical coherence, however, we share some of Okasha's pessimism. Whether or not clades are a unit of selection is ultimately a question of empirical support and theoretical import.