I argue against Matthew Slater’s rejection of what he calls the grounding claim in his stable property cluster account of natural kinds. This claim states that the epistemic value of natural kinds depends on the existence of some ground to bind together a kind’s properties. Using two test cases from academic medicine, I show that grounds are genuinely explanatory of scientific epistemic practices and that the SPC account should not do without them in its philosophical analysis of natural (...) kinds. (shrink)

The homeostatic property cluster theory is widely influential for its ability to account for many natural-kind terms in the life sciences. However, the notion of homeostatic mechanism has never been fully explicated. In 2009, Carl Craver interpreted the notion in the sense articulated in discussions on mechanistic explanation and pointed out that the HPC account equipped with such notion invites interest-relativity. In this paper, we analyze two recent refinements on HPC: one that avoids any reference to the causes of (...) the clustering of properties and one that replaces homeostatic mechanisms with causal networks represented by causal graphs. We argue that the former is too slender to account for some inductive inference in science and the latter, thicker account invites interest-relativity, as the original HPC does. This suggests that human interest will be an un-eliminative part of a satisfactory account of natural kindness. We conclude by discussing the implication of interest-relativity to the naturalness, reality, or objectivity of kinds and indicating an overlooked aspect of natural kinds that requires further studies. (shrink)

Richard Boyd has long campaigned for a view of natural kinds he calls the Homeostatic Property Cluster account. This account has been particularly exciting for philosophers of biology unhappy with traditional essentialism about natural kinds and the views that biological kinds are, in one way or another, “historical entities”. Though defenders of HPC kinds have done much to further articulate the view, many questions about the account remain. One pressing question concerns the way in which HPC kinds are supposed (...) to accommodate our inductive and explanatory practices via causal, homeostatic mechanisms. In addressing the question, I am led to an alternative conception of what a property cluster kind might be. I call my alternative, in deference to its Boydian origins, the Stable Property Cluster account of natural kinds. Rather than emphasizing homeostasis or causal mechanism, the SPC account emphasizes the stability of a property cluster over the various ways stability may be maintained. In virtue of this modest change of emphasis, the SPC account does not advertise itself as an account of a kind of natural kind — it is, I think, an attractive candidate for a general natural kind concept, able to accommodate the diversity of natural kinds we find in the world. (shrink)

The account of natural kinds as stable property clusters is premised on the possibility of separating the epistemic value of natural kinds from their underlying metaphysics. On that account, the co-instantiation of any sub-cluster of the properties associated with a given natural kind raises the probability of the co-instantiation of the rest, and this clustering of property instantiation is invariant under all relevant counterfactual perturbations. We argue that it is not possible to evaluate the stability of (...) a cluster of properties without taking stock of the metaphysical picture used to account for that stability. Thus, even on the stable property cluster account, the epistemic value of natural kinds remains partly grounded in their metaphysical status. (shrink)

I raise a puzzle case for “cluster” accounts of natural kinds—the homeostatic property cluster and stable property cluster accounts, especially—on the basis of their expected treatment of the metaphysics of certain disease kinds. Some kinds, I argue, fail to exhibit the co-instantiated property clusters these cluster views take to be constitutive of natural kinds. Some genetic diseases, for example, have archetypical instances with few or none of the pathological processes or symptoms associated with the kind: (...) their instances are typified by a single dispositional property. I dub such kinds ‘amorphic’, owing to their limited morphology, and try out a number of ways in which these kinds might be treated in terms of property clusters, adapting responses cluster theorists have offered to the problem of polymorphic species. Finding these responses wanting, I conclude that cluster accounts are unlikely to be the best account of the metaphysics of amorphic kinds. (shrink)

Talk of different types of cells is commonplace in the biological sciences. We know a great deal, for example, about human muscle cells by studying the same type of cells in mice. Information about cell type is apparently largely projectible across species boundaries. But what defines cell type? Do cells come pre-packaged into different natural kinds? Philosophical attention to these questions has been extremely limited [see e.g., Wilson (Species: New Interdisciplinary Essays, pp 187–207, 1999; Genes and the Agents of Life, (...) 2005; Wilson et al. Philos Top 35(1/2):189–215, 2007)]. On the face of it, the problems we face in individuating cellular kinds resemble those biologists and philosophers of biology encountered in thinking about species: there are apparently many different (and interconnected) bases on which we might legitimately classify cells. We could, for example, focus on their developmental history (a sort of analogue to a species’ evolutionary history); or we might divide on the basis of certain structural features, functional role, location within larger systems, and so on. In this paper, I sketch an approach to cellular kinds inspired by Boyd’s Homeostatic Property Cluster Theory, applying some lessons from this application back to general questions about the nature of natural kinds. (shrink)

Homeostatic Property Cluster (HPC) theory suggests that species and other biological taxa consist of organisms that share certain similarities. HPC theory acknowledges the existence of Darwinian variation within biological taxa. The claim is that “homeostatic mechanisms” acting on the members of such taxa nonetheless ensure a significant cluster of similarities. The HPC theorist’s focus on individual similarities is inadequate to account for stable polymorphism within taxa, and fails properly to capture their historical nature. A better approach is to (...) treat distributions of traits in species populations as irreducible facts, explained in terms of selection pressures, genealogy, and other evolutionary factors. We call this view Population Structure Theory (PST). PST accommodates the view, implicit in biological systematics, that species are identified by reference to particular historical populations. (shrink)

Psychopathy attracts considerable interdisciplinary interest. The idea of a group of people with abnormal morality and interpersonal relations raises important philosophical, legal, and clinical issues. However, before engaging these issues, we ought to examine whether this category is scientifically grounded. We frame the issue in terms of the question whether ‘psychopathy’ designates a natural kind according to the cluster approaches. We argue that currently there is no sufficient evidence for an affirmative answer to this question. Furthermore, we examine three ways (...) of dealing with the category of psychopathy. We could eliminate the category, revise it, or subscribe to a more encompassing account of kinds, which could capture psychopathy as it is currently conceptualized. We argue that while a revision of the category of psychopathy is to be expected with empirical and theoretical advancements, we also emphasize its role in clinical and forensic research that makes it an important pragmatic kind. (shrink)

The aim of this article is to discuss the relation between indigenous and scientific kinds on the basis of contemporary ethnobiological research. I argue that ethnobiological accounts of taxonomic convergence-divergence patters challenge common philosophical models of the relation between folk concepts and natural kinds. Furthermore, I outline a positive model of taxonomic convergence-divergence patterns that is based on Slater's [2014] notion of “stable property clusters” and Franklin-Hall's [2014] discussion of natural kinds as “categorical bottlenecks.” Finally, I argue (...) that this model is not only helpful for understanding the relation between indigenous and scientific kinds but also makes substantial contributions to contemporary debates about natural kinds.to contemporary debates about natural kinds. (shrink)

This is a dissertation in social ontology, whose goal is to defend a constructivist account of social kinds. First, I show how there is no fully satisfactory characterization or definition of the social, but that we can rely on an intuitive understanding on which entities count as social entities. Second, I clarify what I mean by ‘social category’ or ‘social kind,’ which I define as a partition of entities that bear and share certain social properties. Third, I argue against what (...) I call ‘Natural Boundaries Realism,’ the view according to which there are at least some social kinds that are not constructed. Fourth, I develop my constructivist account, claiming that social kinds are concepts, and showing several ways in which they are created. Fifth, I argue that social kinds may be natural kinds, and that the Stable Property Cluster account of natural kinds is the one that best accommodates the existence of social kinds that are also natural kinds. Finally, I show how values may play a role in the making of social kinds, and how my constructive account accommodates these normative inputs. (shrink)

The world contains many different types of ecosystems. This is something of a commonplace in biology and conservation science. But there has been little attention to the question of whether such ecosystem types enjoy a degree of objectivity—whether they might be natural kinds. I argue that traditional accounts of natural kinds that emphasize nomic or causal–mechanistic dimensions of “kindhood” are ill-equipped to accommodate presumptive ecosystemic kinds. In particular, unlike many other kinds, ecosystemic kinds are “anchored” to the contingent character of (...) species and higher taxa and their abiotic environments. Drawing on Slater (Br J Philos Sci 66(2):375–411, 2015a), I show how we can nevertheless make room for such contingent anchoring in an account of natural kinds of ecosystems kinds. (shrink)

Hilary Kornblith presents an account of inductive inference that addresses both its metaphysical and epistemological aspects. He argues that inductive knowledge is possible by virtue of the fit between our innate psychological capacities and the causal structure of the world. Kornblith begins by developing an account of natural kinds that has its origins in John Locke's work on real and nominal essences. In Kornblith's view, a natural kind is a stable cluster of properties that are bound together in nature. (...) The existence of such kinds serves as a natural ground of inductive inference. Kornblith then examines two features of human psychology that explain how knowledge of natural kinds is attained. First, our concepts are structured innately in a way that presupposes the existence of natural kinds. Second, our native inferential tendencies tend to provide us with accurate beliefs about the world when applied to environments that are populated by natural kinds. (shrink)

Locke’s conception of substance in general or substratum has two relatively widespread interpretations. According to one, substance in general is the bearer of properties, a pure subject, something which sustains properties but itself has no properties. I will call this interpretation traditional, because it has already been formulated by Leibniz. According to the other interpretation, substance is general is something like real essence: an underlying structure which is responsible for the fact that certain observable properties form stable, recurrent (...) class='Hi'>clusters. I will argue that both interpretation are partly right, and what is good in them can be reconciled. The traditional interpretation captures the purpose and signficanc of the idea of substance in general, i.e. the reason why Locke says we have this idea. The real essence view is right about the real world counterpart of the idea, i.e. what sort of entity the idea corresponds to. The paper starts with a review of the strengths and weaknesses of the rival interpretations (I, II). Then I examine which part of the traditional interpretation can be sustained in light of the problems it faces (III). Thereafter I will show that the part of the traditional interpretation which can be sustained cannot stand on its own and needs to be supplemented at one point, and the real essence view can provide what is needed. This, as it were, mixed interpretation will be supported by sketching an argument which is plausible within the context of Locke’s teachings and which explains how Locke could have arrived from the view which the traditional interpretation correctly attributes to him to the view which the real essence interpretation takes him to espouse (IV). The two problematic points in this argument will be taken up in the following two sections. (V, VI). Finally, I will provide some evidence from the Drafts for Locke’s identification of substance and essence (VII). (shrink)

Our prominent definitions of cognition are too vague and lack empirical grounding. They have not kept up with recent developments, and cannot bear the weight placed on them across many different debates. I here articulate and defend a more adequate theory. On this theory, behaviors under the control of cognition tend to display a cluster of characteristic properties, a cluster which tends to be absent from behaviors produced by non-cognitive processes. This cluster is reverse-engineered from the empirical tests that comparative (...) psychologists use to determine whether a behavior was generated by a cognitive or a non-cognitive process. Cognition should be understood as the natural kind of psychological process that non-accidentally exhibits the properties assessed by these tests (as well as others we have not yet discovered). Finally, I review two plausible neural accounts of cognition's underlying mechanisms?one based in localization of function to particular brain regions and another based in the more recent distributed networks approach to neuroscience?which would explain why these properties non-accidentally cluster. While this notion of cognition may be useful for a number of debates, I here focus on its application to a recent crisis over the distinction between cognition and association in comparative psychology. (shrink)

I present and defend a novel version of the homeostatic property cluster account of natural kinds. The core of the proposal is a development of the notion of co-occurrence, central to the HPC account, along information-theoretic lines. The resulting theory retains all the appealing features of the original formulation, while increasing its explanatory power, and formal perspicuity. I showcase the theory by applying it to the problem of reconciling the thesis that biological species are natural kinds with the fact (...) that many such species are polymorphic. (shrink)

All of the attempts to date to find a set of necessary and sufficient conditions for life, in order to provide an essential definition of life, have failed. We only have at our disposal series of lists that contain diverse characteristics usually found in living beings. Some authors have drawn from this fact the conclusion that life is not a natural kind. It will be argued here that this conclusion is too hasty and that if life is understood as a (...) natural kind in the non-essentialist sense of a homeostatic property cluster, it is easy to see why the attempts to find a unique and essentialist definition of life have failed. Understanding life in this way would imply that the pretension to find such a type of definition should be abandoned. (shrink)

Taxa and homologues can in our view be construed both as kinds and as individuals. However, the conceptualization of taxa as natural kinds in the sense of homeostatic property cluster kinds has been criticized by some systematists, as it seems that even such kinds cannot evolve due to their being homeostatic. We reply by arguing that the treatment of transformational and taxic homologies, respectively, as dynamic and static aspects of the same homeostatic property cluster kind represents a good (...) perspective for supporting the conceptualization of taxa as kinds. The focus on a phenomenon of homology based on causal processes (e.g., connectivity, activity-function, genetics, inheritance, and modularity) and implying relationship with modification yields a notion of natural kinds conforming to the phylogenetic-evolutionary framework. Nevertheless, homeostatic property cluster kinds in taxonomic and evolutionary practice must be rooted in the primacy of epistemological classification (homology as observational properties) over metaphysical generalization (series of transformation and common ancestry as unobservational processes). The perspective of individuating characters exclusively by historical-transformational independence instead of their developmental, structural, and functional independence fails to yield a sufficient practical interplay between theory and observation. Purely ontological and ostensional perspectives in evolution and phylogeny (e.g., an ideographic character concept and PhyloCode’s ‘individualism’ of clades) may be pragmatically contested in the case of urgent issues in biodiversity research, conservation, and systematics. (shrink)

Properties come in clusters. It seems impossible, for instance, that a mass could float free, unattached to any other property. David Armstrong takes this as a reductio of the bundle theory and an argument for substrata, while Peter Simons and Arda Denkel reply by supplementing the bundle theory with accounts of property interdependencies. I argue against both views. Virtually all plausible ontologies turn out to be committed to the existence of free masses.

In natural kind debates, Boyd's famous Homeostatic Property Cluster theory (HPC) is often misconstrued in two ways: Not only is it thought to make for a normative standard for natural kinds, but also to require the homeostatic mechanisms underlying nomological property clusters to be uniform. My argument for the illegitimacy of both overgeneralizations, both on systematic as well as exegetical grounds, is based on the misconstrued view's failure to account for functional kinds in science. I illustrate the (...) combination of these two misconstruals with recent entries into the natural kind debate about emotions. Finally, I examine and reject Stich's "Kornblith-Devitt method" as a potential justification of these misconstruals. (shrink)

This paper addresses philosophical issues concerning whether mental disorders are natural kinds and how the DSM should classify mental disorders. I argue that some mental disorders (e.g., schizophrenia, depression) are natural kinds in the sense that they are natural classes constituted by a set of stable biological mechanisms. I subsequently argue that a theoretical and causal approach to classification would provide a superior method for classifying natural kinds than the purely descriptive approach adopted by the DSM since DSM-III. My (...) argument suggests that the DSM should classify natural kinds in order to provide predictively useful (i.e., projectable) diagnostic categories and that a causal approach to classification would provide a more promising method for formulating valid diagnostic categories. (shrink)

Despite many attempts to achieve an adequate definition of living systems by means of a set of necessary and sufficient conditions, the opinion that such an enterprise is inexorably destined to fail is increasingly gaining support. However, we believe options do not just come down to either having faith in a future success or endorsing skepticism. In this paper, we aim to redirect the discussion of the problem by shifting the focus of attention from strict definitions towards a philosophical framework (...) that allows conceiving of living systems as a natural kind, but whereby natural kinds are not to be defined by fixed necessary and sufficient conditions. We argue for a property-cluster kind approach according to which living systems constitute a natural kind with vague boundaries, capable of changing, and whose members do not need to instantiate every property. We draw from Boyd’s homeostatic property-cluster theory and introduce two modifications, one regarding homeostatic mechanisms and another related to the scientific role of kinds. Thus, our view overcomes some difficulties of Boyd’s theory and we are able to account for the natural kindhood of living things. We also emphasize the most appealing features of our approach for specific research fields and address three objections to this sort of approach. (shrink)

One primary goal for metaphysical theories of natural kinds is to account for their epistemic fruitfulness. According to cluster theories of natural kinds, this epistemic fruitfulness is grounded in the regular and stable co- occurrence of a broad set of properties. In this paper, I defend the view that such a cluster theory is insufficient to adequately account for the epistemic fruitfulness of kinds. I argue that cluster theories can indeed account for the projectibility of natural kinds, but not (...) for several other epistemic operations that natural kinds support. Natural kinds also play a role in scientific explanations and categorizations. A theory of natural kinds can only account for these additional kind-based epistemic practices if it also analyzes their causal structure. (shrink)

The article “Dealing with the changeable and blurry edges of living things: a modified version of property-cluster kinds”, written by María J. Ferreira Ruiz and Jon Umerez, was originally published electronically on the publisher’s internet portal on June 29, 2018 without open access.

In this article we show that, even though the classification and diagnosis of Psychiatric Disorders are performed according to essentialist terms, the psychiatric diagnoses currently employed, do not actually meet these criteria. Diagnosis is performed operationally. In this paper, we suggest a change of perspective. We reject essentialism relating to PDs and argue for the Homeostatic Property Cluster model, which allows a greater insight into the ontology of PDs than the operational perspective. More specifically, we argue that the HPC (...) model allows for a synthesis of continuous and discrete methods of understanding the boundaries between PDs. Finally, we specify in a more general manner, the kind of ontology we deal with when adopting the HPC model, arguing that this model can be viewed as a mirror device, reflecting the ontological features of PDs. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Diagnostic Criteria, Psychological Tests, and Ratings Scales: Extending the HistoryPeter Zachar, PhD (bio)Le moigne narrates a history of the development of psychiatric ratings scales as hybrids between psychological tests and diagnostic categories. In his telling, psychological tests seek to quantify population-based traits on which every person has a position and which tend to be conceptualized as being stable. Personality traits are often conceptualized as dispositions. Diagnostic categories represent (...) not trait-like properties of populations but episodic states consisting of clusters of symptoms experienced by individuals with disorders. Ratings, scales, he notes, are hybrids between the two. They are used to quantify psychiatric symptom clusters so that change over time can be measured. Le Moigne argues that these distinctions were initially suggested during the development of measures that could assess outcomes in psychopharmacological treatment studies.With respect to depression, Le Moigne writes that in the 1970s and 1980s something akin to depressive personality was reconceptualized as a temperament. A key move, somewhat reflective of Kraepelin’s notion of a depressive temperament, was to view a dysthymic temperament as both a predisposing factor and an attenuated form of depression. Thus, an episodic state commandeered the predisposing–dispositional role that was assigned to stable personality traits.This conceptual shift allowed test-like ratings scales to be seen as useful for quantifying not just stable traits, but salient features of episodic states that are potentially subject to change in response to interventions. To put it another way, in the development of a psychological test, one goal is to have high test-retest reliability (i.e., stability of measurement). With rating scales used to measure change, one wants the scores to not be as stable; ideally the scores on the later assessments will be lower. According to Le Moigne, when dysthymia was subsequently placed on axis I of the Diagnostic and Statistical Manual of Mental Disorders (DSM)-III (as a syndrome) and segregated from personality disorders which were placed on axis II, personality traits were evicted from the conceptualization of depressive disorders.One perennial feature of psychiatry and psychology is that even if an older idea is superseded [End Page 253] in the view of some thinkers, it can still attract adherents. Indeed, interest in understanding a relationship between personality and attenuated states did not fully disappear. For example, based on research in genetics, the schizophrenia spectrum concept included not only schizophrenia, but also milder conditions such that were conceptualized as personality disorders; that is, schizotypal personality disorder and paranoid personality disorder (Kety, Rosenthal, Wender, & Schulsinger, 1971).During the development of the DSM-IV, some people wanted to add depressive personality disorder to the manual (Phillips, Hirschfeld, Shea, & Gunderson, 1995). It seems to have become a territorial dispute between mood disorder specialists and personality disorder specialists The mood disorders specialists challenged the personality disorder specialists to differentiate depressive personality disorder from early onset, chronic dysthymia. They were able to do so by using criteria such as critical, blaming, and derogatory toward self. After the mood disorders work group proposed incorporating some of those criteria into a revised criteria set for dysthymia, the two sets overlapped. The result was the old criteria for dysthymia were printed in DSM-IV and criteria for depressive personality disorder and the revised criteria for dysthymia were both placed in the appendix.In the DSM-5, Axis II was eliminated and personality disorders were placed alongside all the syndromic symptom clusters at the same level. Even so, interest in attenuated presentations as personality-related lingered still. During the development of the DSM-5 there was some thought to using diagnostic spectra as a meta-structure for organizing the manual (Andrews et al., 2009). One idea was to move some personality disorders into a best fitting spectrum, akin to attenuated forms. This did occur with schizotypal personality disorder which is both in the DSM-5 chapter on schizophrenia and in the chapter on personality disorder. In the schizophrenia chapter it is positioned as the earliest emerging disorder on the spectrum. There was also some interest in grouping avoidant personality disorder with the anxiety disorders, but the evidence supporting such a change was not available.These issues may... (shrink)

Recent systematic studies using newly developed genomic approaches have revealed common mechanisms and principles that underpin the spatial organization of eukaryotic genomes and allow them to respond and adapt to diverse functional demands. Genomes harbor, interpret, and propagate genetic and epigenetic information, and the three‐dimensional (3D) organization of genomes in the nucleus should be intrinsically linked to their biological functions. However, our understanding of the mechanisms underlying both the topological organization of genomes and the various nuclear processes is still largely (...) incomplete. In this essay, we focus on the functional relevance as well as the biophysical properties of common organizational themes in genomes (e.g. looping, clustering, compartmentalization, and dynamics), and examine the interconnection between genome structure and function from this angle. Present evidence supports the idea that, in general, genome architecture reflects and influences genome function, and is relatively stable. However, the answer as to whether genome architecture is a hallmark of cell identity remains elusive. (shrink)

Complex functions of the central nervous system such as learning and memory are believed to result from the modulation of the synaptic transmission between neurons. The sequence of events leading to the fusion of synaptic vesicles at the presynaptic active zone and the detection of this signal at the postsynaptic density involve the activity of ion channels and neurotransmitter receptors. Their accumulation and dynamic exchange at synapses are dependent on their interaction with synaptic scaffolds. These are synaptic structures composed of (...) adaptor proteins that provide binding sites for receptors and channels as well as other synaptic proteins. While in its entirety the synaptic scaffold is a relatively stable structure, individual adaptor proteins exchange at a fast time scale. These properties of scaffolds help to ensure the stability of synaptic transmission while permitting the modulation of synaptic strength. Here, we review the dynamics of the synaptic scaffold and of adaptor proteins in relation to their roles in the organisation of the synapse as well as in the clustering and trafficking of receptor proteins. BioEssays 30:1062–1074, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

The concept of innateness is used to make inferences between various better-understood properties, like developmental canalization, evolutionary adaptation, heritability, species-typicality, and so on (‘innateness-related properties’). This article uses a recently-developed account of the representational content carried by inheritance systems like the genome to explain why innateness-related properties cluster together, especially in non-human organisms. Although inferences between innateness-related properties are deductively invalid, and lead to false conclusions in many actual cases, where some aspect of a phenotypic trait develops in reliance on (...) a genetic representation it will tend, better than chance, to have many of the innateness-related properties. The account also shows why inferences between innateness-related properties sometimes fail and argues that such inferences are especially misleading when applied to human psychology and behaviour because human psychological development is especially reliant on non-genetic inherited representations. (shrink)

The stable core, an inner model of the form $\langle L[S],\in, S\rangle $ for a simply definable predicate S, was introduced by the first author in [8], where he showed that V is a class forcing extension of its stable core. We study the structural properties of the stable core and its interactions with large cardinals. We show that the $\operatorname {GCH} $ can fail at all regular cardinals in the stable core, that the stable (...) core can have a discrete proper class of measurable cardinals, but that measurable cardinals need not be downward absolute to the stable core. Moreover, we show that, if large cardinals exist in V, then the stable core has inner models with a proper class of measurable limits of measurables, with a proper class of measurable limits of measurable limits of measurables, and so forth. We show this by providing a characterization of natural inner models $L[C_1, \dots, C_n]$ for specially nested class clubs $C_1, \dots, C_n$, like those arising in the stable core, generalizing recent results of Welch [29]. (shrink)

We show that in a stable first-order theory, the failure of higher dimensional type amalgamation can always be witnessed by algebraic structures that we call n-ary polygroupoids. This generalizes a result of Hrushovski in [16] that failures of 4-amalgamation are witnessed by definable groupoids. The n-ary polygroupoids are definable in a mild expansion of the language.

In this note we study some local properties ofω-stable groups of finite Morley rank.

In this paper, a size-independent modification of the general detrended fluctuation analysis method is introduced. With this modified DFA, seismic time series pertaining to most seismically active regions of the world from the year1972up to the year2016are comparatively analyzed. An eminent homogeneity of spatial clustering behaviors in worldwide range is detected and DFA scaling exponents coincide with previous results for local regions. Furthermore, universal nontrivial spatial clustering behaviors are revealed from shallow to intermediate-depth earthquakes by varying the depth of the (...) hypocenter: in shallow earthquakes, the depth range corresponding to the minimum spatial clustering is first verified to be spatiotemporal and identical; in intermediate-depth earthquakes, strong weakening long-range correlations compared to shallow earthquakes are unveiled to strengthen the recent findings in seismology. Our work aims to suggest a possible statistical approach to explore the dynamic mechanisms implied in the seismicity as well as in other analogous dynamic evolution processes. (shrink)

A dominant strand of philosophical thought holds that natural kinds are clusters of objects with shared properties. Cluster theories of natural kinds are often taken to be a late twentieth-century development, prompted by dissatisfaction with essentialism in philosophy of biology. I will argue here, however, that a cluster theory of kinds had actually been formulated by William Whewell (1794-1866) more than a century earlier. Cluster theories of kinds can be characterized in terms of three central commitments, all of which (...) are present in Whewell’s work on classification. Like contemporary cluster theorists, Whewell claims that kinds are united by similarity, that many kinds do not have essences, and that there are “gaps” between kinds. Moreover, Whewell advises taxonomists to look for consilience (roughly, convergence) between different classificatory schemes, a recommendation that reinforces the identification of natural classes with property clusters. Thus Whewell was not only an early cluster theorist, but one with important insights into what a cluster theory of kinds means for the practice of classification. (shrink)

Part of a symposium devoted to ‘Prediction, Understanding, and Medicine’, in which Alex Broadbent argues that the nature of medicine is determined by its competences, i.e., which things it can do well. He argues that, although medicine cannot cure well, it can do a good job of enabling people not only to understand states of the human organism and of what has caused them, but also to predict future states of it. From this Broadbent concludes that medicine is (at least (...) in part) essentially a practice of understanding and predicting, not curing. In reply to this bold position, I mount two major criticisms. First, I maintain that the reasons Broadbent gives for doubting that medicine can cure provide comparable reason for doubting that medicine can provide an understanding; roughly, the best explanation of why medicine cannot reliably cure is that we still lack much understanding of health and disease. Second, I object to the claim that a practice is medical only if it facilitates understanding and prediction. Although Broadbent has brought to light certain desirable purposes of medicine that are under-appreciated, my conclusion is that he has not yet provided enough reason to think that understanding and prediction are essential to it. Instead of supposing that medicine has an essence, in fact, I suggest that its nature is best understood in terms of a property cluster. (shrink)

We inquire into the notions of ‘boundary’ and ‘cluster’ in the fields of medical genetics, pharmacogenetics, and population genetics. First we show that the two notions are not well discussed in literature. Then we propose a promising explication of them, in which we argue that clustering is always ‘property laden’, that is, fundamentally dependent on decisions about the properties to be taken into account. In particular we suggest three different kinds of properties that have a role in these decisions. (...) That is, we conclude that boundaries and clusters among humans depend on our way of considering nature. Concepts of ‘race’ and ‘ethnic group’ are discussed too, since they are the most used clusters among humans. (shrink)

Substance dualism is the view that there are two fundamentally different kinds of substances: physical and mental. By contrast, according to property dualism there is only one kind of substance (physical) but two fundamentally different kinds of properties: physical and mental. Property nominalism is the view that there are neither repeatable nor non-repeatable fundamentally predicable entities (i.e. neither universals nor tropes) and that things being a certain way or being related in a certain way must ultimately be accounted (...) for in terms of concrete particulars. In this paper, we consider a number of different kinds of property nominalism and argue that none of them sits well with property dualism. We pay special attention to the question of what it could mean for a property to count as mental given different nominalistic accounts of properties. Our conclusion is that property nominalism and property dualism are not a stable match. This is surprising, since property dualism has usually been understood as a thesis that is neutral about the nature of fundamental ontological categories and the relation between them. (shrink)

A new approach to policy analysis is formulated within the framework of the graph model for conflict resolution. A policy is defined as a plan of action for a decision maker (DM) that specifies the DM’s intended action starting at every possible state in a graph model of a conflict. Given a profile of policies, a Policy Stable State (PSS) is a state that no DM moves away from (according to its policy), and such that no DM would prefer (...) to change its policy given the policies of the other DMs. The profile of policies associated to a PSS is called a Policy Equilibrium. Properties of PSSs are developed, and a refinement is suggested that restricts DMs to policies that are credible in that they are in the DM’s immediate interest. Relationships with existing stability definitions in the graph model for conflict resolution are then explored. (shrink)

A model is proposed that deals with the observed collinearities (spatial, temporal and quantitative) of Hox gene expression during pattern formation along the primary and secondary axes of vertebrates. In particular, in the proximodistal axis of the developing limb, it is assumed that a morphogen gradient is laid down with its source at the distal tip of the bud. The extracellular signals in every cell of the morphogenetic field are transduced and uniformly amplified so that molecules are produced in the (...) nucleus with appropriate physicochemical properties. These molecules can exert a concentration‐dependent force on the Hox cluster. It is assumed that, before activation, the Hox cluster is packaged as an elongated rigid body inside the chromatin and is covered by a coat that prevents the transcription factors reaching the genes of the cluster. The transcription factors are confined to the interchromatin domain and their density decreases with their distance from the chromatin surface. A gradual increase in the extracellular morphogen concentration causes a corresponding increase in the number of the nuclear molecules and the resulting bigger force pushes the Hox cluster toward the interchromatin domain. The step‐by‐step translocations of the Hox cluster initiate the consecutive exposure of genes to their transcription factors. The model explains how gene activation is triggered and it describes spatial, temporal and quantitative collinearities at the initial stages of gene expression. Some recent experiments of Hox deletions and duplications are accounted for by the model. BioEssays 26:189–195, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

An option available to an agent is stable if it maximizes expected utility on the hypothetical assumption that the agent is going to choose it. As is well known, some decision problems lack a stable solution. Paul Weirich (1986 and 1988) has recently proposed a decision principle which prescribes that the option chosen should be at least weakly stable--or "weakly ratifiable", to use his terminology. According to him, full stability is an excessively strong demand. I shall argue (...) that Weirich's proposal conflicts with the familiar condition of dominance. But I shall also prove that this difficulty can be avoided if we replace weak stability by "moderate" stability--where the latter property is somewhat stronger than the former. It will be seen, however, that this modification does not help against other ailments connected with stability. In particular, to heed the demand of stability (of any kind) is to engage in a form of "wishful acting". Also, the different stability demands all conflict with a close relative of the dominance condition: the condition of "indifference". According to this condition, two actions are equally choiceworthy if they would always lead to the same outcomes--whatever state the world is in. On the other hand, the conditions of dominance and indifference would both be satisfied if we replaced a demand for stability (of some kind) by a related but distinct principle of "retrievability". Retrievability and (full) stability are mutually independent properties of options, but each of them entails moderate stability. The paper ends with a discussion of the relevance of retrievability to theories of choiceworthiness and practical reason. (shrink)

A private property right is a collection of particular rights that relate to the control of an object. The ground for such moral rights rests on the value of project pursuit. It does so because the individual ownership of particular objects is intimately related to the formation and application of a coherent set of projects that are the major parts of a self-shaped life. Problems arise in explaining how unowned property is appropriated. Unilateral acts with regard to an (...) object, e.g., mixing in one’s labor into it, probably don’t ground particular rights to private property. Nor do bilateral contracts since a stable pre-institutional contract with regard to appropriation is not likely to form. However, a conventional method of appropriation can allow for such appropriation while at the same time preserving the pre-institutional nature of such rights. This theory can also account for a person’s property rights in her own body. However, the value of project formation requires that persons have at least some private property that is to serve as the object of their projects. These positive rights to property undermine the libertarian claim that all non-commitment-based rights are negative. However, a further empirical argument is needed in order to justify protecting these positive moral rights to private property by positive legal rights. (shrink)

We define an $\mathfrak{R}$-group to be a stable group with the property that a generic element can only be algebraic over a generic. We then derive some corollaries for $\mathfrak{R}$-groups and fields, and prove a decomposition theorem and a field theorem. As a nonsuperstable example, we prove that small stable groups are $\mathfrak{R}$-groups.