Machery neglects the crucial role of concepts in psychological explanation, as well as the efforts of numerous of the last 40 years to provide an account of that role. He rightly calls attention to the wide variation in people's epistemic relations to concepts but fails to appreciate how externalist and kindred proposals offer the needed stability in concepts themselves that underlies that variation.

To subscribe to the embodied mind (or embodiment) framework is to reject the view that an individual’s mind is realized by her brain alone. As Clark ( 2008a ) has argued, there are two ways to subscribe to embodiment: bodycentrism (BC) and the extended mind (EM) thesis. According to BC, an embodied mind is a two-place relation between an individual’s brain and her non-neural bodily anatomy. According to EM, an embodied mind is a threeplace relation between an individual’s brain, her (...) non-neural body and her non-bodily environment. I argue that BC can be given a weak and a strong interpretation, according to whether it accepts a functionalist account of the contribution of the non-neural body to higher cognitive functions and a computational account of the contents of concepts and the nature of conceptual processing. Thus, weak BC amounts to an incomplete version of EM. To accept a weak BC approach to concepts is to accept concept-empiricism. I raise four challenges for concept-empiricism and argue that what is widely taken as evidence for concept-empiricism from recent cognitive neuroscience could only vindicate weak BC if it could be shown that the non-neural body, far from being a tool at the service of the mind/brain, could be constitutive of the mind. If correct, EM would seem able to vindicate the claim that both bodily and non-bodily tools are constitutive of an individual’s mind. I scrutinize the basic arguments for EM and argue that they fail. This failure backfires on weak BC. One option left for advocates of BC is to endorse a strong, more controversial, BC approach to concepts. (shrink)

A number of authors have suggested that a conditional analysis of dispositions must take roughly the following form: Thing X is disposed to produce response R to stimulus S just in case, if X were exposed to S and surrounding circumstances were auspicious, then X would produce R. The great challenge is cashing out the relevant notion of ‘auspicious circumstances’. I give a general argument which entails that all existing conditional analyses fail, and that there is no satisfactory way to (...) define ‘auspicious circumstances’ just in terms of S, R, and X. Instead, I argue that the auspicious circumstances C for the manifestation of a disposition constitute a third irreducible element of that disposition, and that to pick out (or to ‘individuate’) that disposition one must specify C along with S and R. This enables a new conditional analysis of dispositions that gives intuitively satisfying answers in cases that pose problems for other approaches. (shrink)

Ethological theory standardly attributes representational content to animal signals. In this article I first assess whether Ruth Millikan’s teleosemantic theory accounts for the content of animal signals. I conclude that it does not, because many signals do not exhibit the required sort of cooperation between signal‐producing and signal‐consuming devices. It is then argued that Kim Sterelny’s proposal, while not requiring cooperation, sometimes yields the wrong content. Finally, I outline an alternative view, according to which consumers alone are responsible for conferring (...) representational status and determining content. I suggest that consumer‐based teleosemantics reconstruct the content of both cooperative and noncooperative signals and explain how a given trait can mean different things to different consumers. †To contact the author, please write to: Department of Philosophy, King’s College London, Strand, London WC2R 2LS, U.K.; e‐mail: [email protected]. (shrink)

In this paper, I suggest that the notion of module explicitly defined by Peter Carruthers in The Architecture of The Mind (Carruthers 2006) is not really In use in the book. Instead, a more robust notion seems to be actually in play. The more robust notion, albeit implicitly assumed, seems to be far more useful for making claims about the modularity of mind. Otherwise, the claims would become trivial. This robust notion will be reconstructed and improved upon by putting it (...) into a more general framework of mental architecture. I defend the view that modules are the outcome of structural rather than functional decomposition and that they should be conceived as near decomposable systems. (shrink)

This book presents vigorous and wide-ranging arguments in defense of an Aristotelian metaphysical scheme along fairly orthodox Thomistic lines. The central claim is that the items that populate the world have real essences – natures that mind-independently define what each such item is. This Aristotelian essentialism, Oderberg begins by telling us, is a different doctrine from what has recently been called ‘essentialism’, and a more powerful one . For recent essentialism has treated a thing's essence as merely all those properties (...) that the thing takes with it across all possible worlds – and here modality gets presupposed in order to explain essentialness, when the order should be reversed.We can observe essences, Oderberg holds, even though the observation is indirect, and even though knowing what to make of our observations requires applying metaphysical knowledge. Positivism-inspired worries that there is something unfactual about modal claims, and hence about essences, are unfounded . Claims about essences do have factual content, but not because they merely express our concepts or our grammar, and not because they simply report empirical findings . True reports of the essences of objects articulate a metaphysical insight from Aristotle: an object's essence is a compound of its substantial form and its prime matter . Its form actuates potentialities of its matter . The laws of nature derive from essences, and hence are necessary rather than contingent . Artifacts are ‘accidental unities’ of individual substances and …. (shrink)

Byrne & Hilbert are right that it might be an objective fact that a particular tomato is unique red, but wrong that it cannot simultaneously be yellowish-red (not only objectively, but from somebody else's point of view). Sensory categorization varies among organisms, slightly among conspecifics, and sharply across taxa. There is no question of truth or falsity concerning choice of categories, only of utility and disutility. The appropriate framework for color categories is Nominalism and Pluralistic Realism.

Lewis’s view of the way conventions are passed on may have some especially interesting consequences for the study of language. I’ll start by briefly discussing agreements and disagreements that I have with Lewis’s general views on conventions and then turn to how linguistic conventions spread. I’ll compare views of main stream generative linguistics, in particular, Chomsky’s views on how syntactic forms are passed on, with the sort of view of language acquisition and language change advocated by usage-based or construction grammars, (...) which seem to fit better with Lewis’s ideas. Then I will illustrate the interest of Lewis’s perspective on the dissemination of conventions with a variety of linguistic examples. (shrink)

The structuralist heritage in linguistics continues to obscure the essential properties of natural language as an empirical phenomenon. It is argued that the new framework of autopoiesis possesses a greater explanatory power, as it assumes the connotational na-ture of language. The key notions of representation, sign and signification, interpreta-tion, intentionality and communication, and reciprocal causality, approached from the autopoietic angle, allow for deeper insights into the essence of language which is as a kind of adaptive behavior of an organism involving (...) a system constituted by signs of signs. (shrink)

Defense of a non-psychological dynamics of demonstrative thoughts.

This paper re-addresses Quine's indeterminacy of translation/inscrutability of reference thesis, as a problem for cognitive theories of content. In contradistinction with Quine's behavioristic semantics, theories of meaning, or content, in the cognitivist tradition endorse intentional realism, and are prone to be unsympathetic to Quine's thesis. Yet, despite this fundamental difference, I argue that they are just as vulnerable to the indeterminacy. I then argue that the vulnerability is rooted in a theoretical commitment tacitly shared with Quine, namely, the commitment to (...) the view that the perceptual input to the cognitive system is extensional - differentiating objects, but not the aspects (or, properties) they manifest. Thus, input extensionalism, and not behaviorism, is what forces the indeterminacy. I conclude by suggesting that the solution to Quine's indeterminacy problem hinges on the elaboration of an intensional theory of perceptual input, and of content in general. (shrink)

“Naturalized epistemology” is a recent attempt to transform the theory of knowledge into a branch of natural science. Traditional epistemologists object to this proposal on the grounds that it eliminates the distinctively philosophical content of epistemology. In this thesis, I argue that traditional philosophers are justified in their reluctance to accept naturalism, but that their ongoing inability to refute it points to deeper problems inherent in traditional epistemology. I establish my thesis first by critiquing three versions of naturalism, showing that (...) each version either fails to implement its objectives consistently or starts from dubious objectives. “Optimistic naturalism” attempts to use naturalistic methods to give positive answers to traditional epistemological questions (such as by affirming that our beliefs can be justified). This fails because the form of traditional questions requires the concept “belief,” a concept that I argue naturalistic methodology cannot countenance (because of the severe constraints of naturalistic semantic theory). “Pessimistic naturalism,” the version advocated by Quine, is more consistent with naturalistic methodology, but fails because hidden behind its conclusions are assumptions (such as the underdetermination thesis) that cannot themselves be naturalized in the full context of scientific evidence. A final attempt to naturalize epistemology, deflationary naturalism, dispenses with traditional questions entirely, urging that the terms “knowledge” and “justification” be taken as mere pragmatic devices whose use can, nevertheless, be studied scientifically. Curiously, this view fails to take account of important facts about the actual use of those terms, as studied by psychologists. In the end, despite problems with each of these versions, traditional philosophers can learn something from their encounter with naturalism. In the course of showing how various naturalistic doctrines cannot themselves be naturalized, I identify the flaws in traditional epistemology (such as its reliance on a priorism, and its resulting inability to articulate a workable empirical foundationalist theory of justification) that make naturalism harder to challenge. These flaws must be corrected if philosophers are to preserve the autonomy of their discipline. (shrink)

Kim's argument appears to render causally efficacious emergence impossible: Hume's argument appears to render normative emergence impossible, and, in its general form, it precludes any emergence at all. I argue that both of these barriers can be overcome, and, in fact, that they each constitute reductions of their respective underlying presuppositions. In particular, causally efficacious ontological emergence can be modeled, but only within a process metaphysics, thus avoiding Kim's argument, and making use of non-abbreviatory forms of definition, thus avoiding Hume's (...) argument. I illustrate these points with models of the emergent nature of normative function and of representation. (shrink)

This paper argues that it is possible for suffering to occur in the absence of phenomenal consciousness – in the absence of a certain sort of experiential subjectivity, that is. (Phenomenal consciousness is the property that some mental states possess, when it is like something to undergo them, or when they have subjective feels, or possess qualia.) So even if theories of phenomenal consciousness that would withhold such consciousness from most species of non-human animal are correct, this neednt mean that (...) those animals dont suffer, and arent appropriate objects of sympathy and concern. (shrink)

Our reply is in three parts. The first part concerns some foundational issues in the debate about color realism. The second part addresses the many objections to the version of physicalism about color ("productance physicalism") defended in the target article. The third part discusses the leading alternative approaches and theories endorsed by the commentators.

Philosophers and psychologists seeking an accessible introduction to current neuroscience will find much value in this volume. Befitting the neuroscientific focus on sensory processes, many essays address explicitly the binding problem. Theoretical and experimental work pertaining to the “temporal synchronicity” solution is prominent. But there are also some surprising implications for current philosophical concerns, such as the intemalism/extemalism debate about representational content, epistemological realism, a “bottom-up” approach to naturalizing intentionality, Humean concerns about the self, and implications from phantom-limb phenomena. Higher-level (...) theorists about the mind ignore results like these from current neuroscience at their own peril, at least from the point of view of discourse worthy of serious attention as the sciences of the mind/brain push forward into the 21st century. (shrink)

I begin with a rather unpromising dispute that Nozick once had with Ian Hacking in the pages of the London Review of Books, in which both vied with one another in their enthusiasm to repudiate the thesis that some human people or peoples are closer than others to animality. I shall attempt to show that one can build, on the basis of Nozick’s discussion of rationality, a defense of the view that the capacity tor language places human rationality out of (...) reach of a comparison with animals. The difference rests, paradoxically, on the human capacity tor irratianality. Irrationality depends on the capacity tor language, which allows the detachment of explicit thoughts from their underlying dynamic implementation; these, in turn, condition the essential disputability of principles of rationality. That is what places every human potentially -- if not actually -- on the other side of an unbridgeable gulf that separates us from other animals. (shrink)

The naturalization of intentionality requires explaining the supervenience of the normative upon the descriptive. Proper function theory provides an account of the semantics of natural representations, but not of that of signs that require the observance of norms. I therefore distinguish two senses of "meaning" and two correlative senses of "representation" and explain their relationship to one another. I distinguish between indicative signs and semiotic devices. The former are indicators of the presence of some phenomenon. The latter are rule-governed devices (...) whose content derives from a set of recognized conventions for their use in the context of a system of other such signs. Each of these kinds of signs has its own kind of meaning, and each of these senses of meaning and representation has an important place in cognitive science. The indicative sign is fundamental and grounds the intentionality of semiotic devices. But the theory of indicative signs is insufficient for a general theory of intentionality and representation. Cognitive science must therefore comprise both a biological program aimed at understanding representation in the indicative sense and a social/ecological/linguistic program aimed at understanding the relational phenomena that allow semiotic meaning. (shrink)

Sometimes your concept and mine have exactly the same content. When this is so, it is comparatively easy for me to understand what you say when you deploy your concept, for us to disagree, agree, and so on. But what if your concept and mine do not have exactly the same content? This question has occupied a number of philosophers, including Paul Churchland, Jerry Fodor, and Ernie Lepore. This paper develops a novel and rigorous measure of concept similarity, Proportion, such (...) that concepts with different contents but sufficiently high Proportion scores will also conduce to understanding, agreement, and disagreement. (shrink)

I consider the question of whether success-linked theories of content – theories like those of Ramsey (1927), Millikan (1984) and Blackburn (2005) which take there to be a definitional link between representational content and behavioral success – are consistent with the plausible claim that we can use content-attributions to explain behavioral success. Peter Godfrey-Smith (1996) argues that success-linked theories of content are too closely linked to success to be able to explain it. Against this, I present a plausible account of (...) how content-attributions make available good explanations of behavioral success, and argue that if we want our content-attributions to be able to do this explanatory work, then we actually need to embrace a success-linked theory of content. (shrink)

Are attributions of content and function determinate, or is there no fact of the matter to be fixed? Daniel Dennett has argued in favor of indeterminacy and concludes that, in practice, content and function cannot be fixed. The discovery of an electrical modality in vertebrates offers one concrete instance where attributions of function and content are supported by a strong scientific consensus. A century ago, electroreception was unimagined, whereas today it is widely believed that many species of bony fish, amphibians, (...) sharks, skates, and rays possess this non-human sensory modality. A look at the history of science related to this discovery reveals a highly interdisciplinary endeavor, encompassing ethology, behavioral analysis, neuroscience, and evolutionary biology. While each area provides important evidence, none is sufficient on its own to fix content and function. Instead, I argue that an interdisciplinary, neuroethological approach is required to carry out such determinations. Further, a detailed consideration of biological research suggests that while content and function claims are empirically underdetermined and uncertain, there is insufficient reason to believe in an additional problem of indeterminism. In particular, Dennett's indeterminism arises from a research methodology -- logical adaptationism -- that generates evidence from only one of the areas of neuroethology. However, logical adaptationism does not reflect adaptationism as it is practiced in contemporary biology. I conclude that Dennett is faced with a dilemma: On the one hand, he can hold to logical adaptationism and the indeterminism that results from it, while giving up the relevance of his arguments to biological practice. On the other, he can embrace a more accurate version of adaptationism -- one which plays a role in a larger neuroethological framework -- but from which no strong indeterminacy claims follow. (shrink)

It is argued that understanding is the norm of political discourse, and it is shown why political assertions can be epistemically problematic within a liberal democracy even when asserted knowledgeably.

This paper introduces the Cummins Functions Approach to neural representations, which aims to capture the notion of representation that is relevant to contemporary neuroscientific practice. CFA shares the common view that “to be a representation of X” amounts to “having the function of tracking X,” but maintains that the relevant notion of function is defined by Robert Cummins’s account. Thus, CFA offers a notion of neural representation that is dependent on explanatory context. I argue that CFA can account for the (...) normativity of neural representations, and defend its dependence on explanations. (shrink)

Philosophical views of language have traditionally been focused on notions of truth. This is a reconstructive view in that we try to extract from an utterance in context what the sentence and speaker meaning are. This focus on meaning extraction from word sequences alone, however, is challenged by utterances which combine different types of figures. This paper argues that what appears to be a special case of ironic utterances—ironic metaphorical compounds—sheds light on the requirements for psychological plausibility of a theory (...) of communication and thus presents a different view of communication and language to that dominant in philosophy of language. In the view presented here, the hearer does not extract the speaker’s communicative intention from the sequence of words in the utterance, but from other channels, so as to constrain the inferential space for the sentence and speaker meaning. Specifically, we examine an example of ironic metaphor discussed by Stern. He argues that ironic content is logically dependent on metaphorical content, but makes no claims about how psychologically plausible this is in terms of the processing order. We argue that a straightforward translation of logical order into temporal order makes little sense. The primary sticking point is that without a prior understanding of the speaker’s communicative intentions, it is computationally more challenging to process the sub-component meanings. An alternative solution based on communicative channels leads us to a more psychologically plausible account of the structure of communicative acts and intentions. This provides support for the psychological realism of a richer theory of communicative intent. (shrink)

The extensive philosophical discussions and analyses in recent decades of function-talk in biology have done much to clarify what biologists mean when they ascribe functions to traits, but the basic metaphysical question—is there genuine teleology and design in the natural world, or only the appearance of this?—has persisted, as recent work both defending, and attacking, teleology from a Darwinian perspective, attest. I argue that in the context of standard contemporary evolutionary theory, this is for the most part a verbal, rather (...) than a substantive dispute: the disputants are talking past one another. To justify this claim I develop a general framework within which reductionist views, such as the standard ‘etiological’ account of biofunctions, occupy an intermediate position between what I call full-blooded realism and full-blooded anti-realism, and suggest that whether such views count as ‘realist’ views has no objective, theory-neutral answer. (shrink)

Representations may have descriptive content, directive content, or both, but little explicit attention has been given to the problem of distinguishing representations of these three kinds. We do not know, for instance, what determines whether a given representation is a directive instructing its consumer to perform some action or has descriptive content to the effect that the action in question has a certain value. This paper considers what it takes for a representation to have directive content. The first part of (...) the paper presents the Liberal View, which might be taken to be the default position on this issue. The Liberal View has some attractions, but as the second part shows, these are less conclusive than they might at first appear, and there is much to be said for an alternative, the Strict View. (shrink)

The present paper introduces a simple framework for modeling the relationship between environmental states, perceptual states, and action. The framework represents situations where an agent’s perceptual state forms the basis for choosing an action, and what action the agent performs determines the agent’s payoff, as a function of the environmental conditions in which the action is performed. The framework is used as the basis for a simulation study of the sorts of correspondence between perceptual and environmental states that are important (...) for successful navigation of the world. Some of the results are surprising and conflict with long held views about the kind of perception-to-environment correspondence that is important for knowledge of the world. The results also raise doubts concerning the view that our perceptual states provide a basis for knowledge of the real structure of the external world. (shrink)

In a trio of recent articles, Johnson and Nado defend a form of metasemantic dispositionalism, arguing for a novel approach to the “error”-problem, based on speakers’ dispositional states under what they call a state of “full information”. In this article, I argue that their brand of dispositionalism fails to solve the “error”-problem, because of what I think of as counterexamples to it. In the final sections, I propose a way to amend the theory to shield it from some of the (...) counterexamples, based on the idea that what determines meaning is not only dispositions to apply words under full information, but also dispositions to evaluate one’s prior usage, under full information. (shrink)

Similarity-based cognition is commonplace. It occurs whenever an agent or system exploits the similarities that hold between two or more items—e.g., events, processes, objects, and so on—in order to perform some cognitive task. This kind of cognition is of special interest to cognitive neuroscientists. This paper explicates how similarity-based cognition can be understood through the lens of radical enactivism and why doing so has advantages over its representationalist rival, which posits the existence of structural representations or S-representations. Specifically, it is (...) argued that there are problems both with accounting for the content of S-representations and with understanding how neurally-based structural similarities can work as representations in guiding intelligent behavior. Finally, with these clarifications in place, it is revealed how radical enactivism can commit to an account of similarity-based cognition in its understanding of neurodynamics. (shrink)

This article reviews The expressive moment: How interaction (with music) shapes human empowerment 9780262034937.

Which factors are relevant for the assessment of the exercise of our capacities to reason and argue? And what do these factors reveal about the nature of these capacities? The aim of this paper is to address these questions. In order to do this, we will try to explain, without presupposing the unviable use of sophisticated conceptual capacities, how a person can aim to identify correct reasons or arguments and properly satisfy such purpose. The contribution of our proposal resides in (...) the linkage between certain conceptions of the implicit knowledge, the notion of proper function, and some of the results in the experimental research on metacognition, with the aim of gaining a better understanding of the exercise of our capacities to reason and argue. (shrink)

Many philosophers worry that cognitive scientists apply the concept REPRESENTATION too liberally. For example, William Ramsey argues that scientists often ascribe natural representations according to the “receptor notion,” a causal account with absurd consequences. I rehabilitate the receptor notion by augmenting it with a background condition: that natural representations are ascribed only to systems construed as organisms. This Organism-Receptor account rationalizes our existing conceptual practice, including the fact that scientists in fact reject Ramsey’s absurd consequences. The Organism-Receptor account raises some (...) worrying questions, but as a more faithful characterization of scientific practice it is a better guide to conceptual reform. (shrink)

Predictive processing and its apparent commitment to explaining cognition in terms of Bayesian inference over hierarchical generative models seems to flatly contradict the pragmatist conception of mind and experience. Against this, I argue that this appearance results from philosophical overlays at odd with the science itself, and that the two frameworks are in fact well-poised for mutually beneficial theoretical exchange. Specifically, I argue: first, that predictive processing illuminates pragmatism’s commitment to both the primacy of pragmatic coping in accounts of the (...) mind and the profound organism-relativity of experience; second, that this pragmatic, “narcissistic” character of prediction error minimization undermines its ability to explain the distinctive normativity of intentionality; and third, that predictive processing therefore mandates an extra-neural account of intentional content of exactly the sort that pragmatism’s communitarian vision of human thought can provide. (shrink)

In 1956 U. T. Place proposed that consciousness is a brain process. More attention should be paid to his word ‘process’. There is near-universal agreement that experiences are processive—as witnessed in the platitude that experiences are occurrent states. The abandonment of talk of brain processes has benefited functionalism, because a functional state, as it is usually conceived, cannot be a process. This point is dimly recognized in a well-known but little-discussed argument that conscious experiences cannot be functional states because the (...) former are occurrent, while the latter are dispositional. That argument fails, but it can be made sound if we reformulate it with the premise that occurrent states are processive. The only way for functionalists to meet the resulting challenge is to abandon the standard individuation of functional states in terms of purely abstract causal roles. (shrink)

In this paper, we defend a representational approach to at least some kinds of non-human psychopathology. Mentally-ill non-human minds, in particular in delusions, obsessive-compulsive disorders and similar cognitive states, are traditionally understood in purely behavioral terms. In contrast, we argue that non-human mental psychopathology should be at least sometimes not only ascribed contentful mental representation but also understood as really having these states. To defend this view, we appeal to the interactivist account of mental representation, which is a kind of (...) a constructive approach to meaning. We follow Mark Bickhard in assuming that only an organism – either human or non-human – capable of detecting its own misrepresentations is representational. However, under his autonomy-based account of biological function these minds are incapable of misrepresentations because these minds are, ex hypothesi, unable to detect error in such representations. To solve this problem, we argue that adding a historical dimension – as in Millikan’s view on mental representations – to Bickhard’s account of function makes mental misrepresentation of mentally-ill minds possible. Using Bickhard’s dynamic account of function, it is possible to explain why delusions and other mental disorders can be seen as locally functional. However, an etiological dimension can further explain why misrepresentations seem to be globally dysfunctional. Even if representational or biosemiotic hypotheses about non-human psychopathology are difficult to confirm empirically, we defend the view that they can enrich our understanding of the causes and development of such pathologies, and may constitute a new progressive research programme. (shrink)

This paper addresses several objections that have been leveled against a behavioral approach to psychological categories. It reconstructs and critically assesses the so-called causal objection; alleged counterexamples whereby one can exhibit the typical behaviors associated with a psychological phenomenon without exhibiting the latter, including Lewis’ “perfect actor” case and Kirk’s “zombie”; alleged counterexamples whereby organisms can exemplify psychological phenomena without exhibiting any behavior associated with them, including Armstrong’s imagined brain in a vat, Putnam’s “super-super-spartans” scenario, and related cases; and the (...) holistic objection. Mistaken assumptions in each of these objections are pinpointed. The paper starts with a brief characterization of behaviorism about psychological categories and a summary of the particular version thereof supported here, which draws upon Ryle and Skinner, among others. (shrink)

Most cognitive scientists nowadays tend to think that at least some of the mind’s capacities are the product of biological evolution, yet important conceptual problems remain for all scientists in order to be able to speak coherently of mental or cognitive systems as having evolved naturally. Two of these important problems concern the articulation of adequate, interesting, and empirically useful concepts of homology and variation as applied to cognitive systems. However, systems in cognitive science are usually understood as functional systems (...) of some sort. Thus, to be able to talk about functional systems being homologous requires having a solid, adequate, and empirically articulated concept of functional homology—and the same is true about functional variation. Here I construct an original concept of functional homology that, in my view, adequately systematizes a number of actual uses of the word “functional homology” in a variety of biological disciplines and in ethology. I also propose a number of criteria for the empirical application of the concept that are analogous to the criteria that are currently used in comparative biology, ethology, and molecular developmental genetics. Then I construct a concept of functional variation on the basis of this concept of homology. (shrink)