Misidentification syndromes occur commonly in neuropsychiatric practice and can be explained through aberrant integration of recollection and familiarity, in keeping with a dysfunction at the level of the attributional system in the new integrative memory model. We examine neuroimaging findings associated with Fregoli and Capgras syndromes and compare these with the proposed neural substrate of the integrative memory model supporting the core and attribution functions.

This book originated at a small and informal workshop held in December of 1992 in Idyllwild, a relatively secluded resort village situated amid forests in the ...

We analyze the precise modal commitments of several natural varieties of set-theoretic potentialism, using tools we develop for a general model-theoretic account of potentialism, building on those of Hamkins, Leibman and Löwe [14], including the use of buttons, switches, dials and ratchets. Among the potentialist conceptions we consider are: rank potentialism, Grothendieck–Zermelo potentialism, transitive-set potentialism, forcing potentialism, countable-transitive-model potentialism, countable-model potentialism, and others. In each case, we identify lower bounds for the modal validities, which are generally either S4.2 or S4.3, (...) and an upper bound of S5, proving in each case that these bounds are optimal. The validity of S5 in a world is a potentialist maximality principle, an interesting set-theoretic principle of its own. The results can be viewed as providing an analysis of the modal commitments of the various set-theoretic multiverse conceptions corresponding to each potentialist account. (shrink)

This paper introduces the philosophy of Grace Andrus de Laguna in order to renew interest in it. I show that, in the 1910s and 1920s, she develops ideas and arguments that are also found playing key roles in the development of analytic philosophy decades later. Further, I describe her sympathetic, but acute, criticism of pragmatism and Heideggerian ontology, and situate her work in the tradition of American, speculative philosophy. Before 1920, we will see, de Laguna appeals to multiple realizability to (...) undermine reductionism in science, to support perspectival, scientific realism and, with help from a private language argument, to favour the view that mental states are classified by behavioural, teleological roles over what came to be called ‘type physicalism’. Her view of speech, mostly developed in the 1920s, tells us that its primary role is coordinating group behaviour rather than expressing thoughts. Belief is understood in terms of its causal role, including its causal relations to other kinds of mental states, when coordinating group behaviour. Thought is similarly understood. In developing her theory of mind, de Laguna rejects the pragmatist claims that belief can be reduced to dispositions to behaviour and that thought’s function is to address specific, rather than general, problems. She also favours meaning holism and rejects the analytic–synthetic distinction. In later work, de Laguna argues that individuals’ activity of self-maintenance brings universals, conceived of as irreducible potentialities, into being and makes them increasingly determinate. Further, she identifies the existence of all individuals with forms of self-maintenance and takes the existence of people to include maintenance of the cultural world. Such a unified treatment of existence, she holds, permits making its evolution intelligible. Heidegger’s view of being is rejected for not permitting this. All de Laguna’s work, we will see, fits a vision of philosophy as the systematic, imaginative and naturalistic examination of being as well as a source of criticism of science. (shrink)

I bring out the limitations of four important views of what the target of useful climate model assessment is. Three of these views are drawn from philosophy. They include the views of Elisabeth Lloyd and Wendy Parker, and an application of Bayesian confirmation theory. The fourth view I criticise is based on the actual practice of climate model assessment. In bringing out the limitations of these four views, I argue that an approach to climate model assessment that neither demands too (...) much of such assessment nor threatens to be unreliable will, in typical cases, have to aim at something other than the confirmation of claims about how the climate system actually is. This means, I suggest, that the Intergovernmental Panel on Climate Change ’s focus on establishing confidence in climate model explanations and predictions is misguided. So too, it means that standard epistemologies of science with pretensions to generality, e.g., Bayesian epistemologies, fail to illuminate the assessment of climate models. I go on to outline a view that neither demands too much nor threatens to be unreliable, a view according to which useful climate model assessment typically aims to show that certain climatic scenarios are real possibilities and, when the scenarios are determined to be real possibilities, partially to determine how remote they are. (shrink)

This paper shows that during the first half of the 1960s The Journal of Philosophy quickly moved from publishing work in diverse philosophical traditions to, essentially, only publishing analytic philosophy. Further, the changes at the journal are shown, with the help of previous work on the journals Mind and The Philosophical Review, to be part of a pattern involving generalist philosophy journals in Britain and America during the period 1925-1969. The pattern is one in which journals controlled by analytic philosophers (...) systematically promote a form of critical philosophy and marginalise rival approaches to philosophy. This pattern, it is argued, helps to explain the growing dominance of analytic philosophy during the twentieth century and allows characterising this form of philosophy as, at least during 1925-1969, a sectarian form of critical philosophy. (shrink)

ABSTRACTThis paper is concerned with the reasons for the emergence and dominance of analytic philosophy in America. It closely examines the contents of, and changing editors at, The Philosophical Review, and provides a perspective on the contents of other leading philosophy journals. It suggests that analytic philosophy emerged prior to the 1950s in an environment characterized by a rich diversity of approaches to philosophy and that it came to dominate American philosophy at least in part due to its effective promotion (...) by The Philosophical Review’s editors. Our picture of mid-twentieth-century American philosophy is different from existing ones, including those according to which the prominence of analytic philosophy in America was basically a matter of the natural affinity between American philosophy and analytic philosophy and those according to which the political climate at the time was hostile towards non-analytic approaches. Furthermore, our reconstruction suggests a new perspective on the nature of 1950s analytic philosophy. (shrink)

The lottery preparation, a new general kind of Laver preparation, works uniformly with supercompact cardinals, strongly compact cardinals, strong cardinals, measurable cardinals, or what have you. And like the Laver preparation, the lottery preparation makes these cardinals indestructible by various kinds of further forcing. A supercompact cardinal κ, for example, becomes fully indestructible by <κ-directed closed forcing; a strong cardinal κ becomes indestructible by κ-strategically closed forcing; and a strongly compact cardinal κ becomes indestructible by, among others, the forcing to (...) add a Cohen subset to κ, the forcing to shoot a club Cκ avoiding the measurable cardinals and the forcing to add various long Prikry sequences. The lottery preparation works best when performed after fast function forcing, which adds a new completely general kind of Laver function for any large cardinal, thereby freeing the Laver function concept from the supercompact cardinal context. (shrink)

I offer an account of the ontology of emotions and their expressions, drawing some morals for the view that we can perceive others' emotions in virtue of seeing their expressions.

The dream solution of the continuum hypothesis would be a solution by which we settle the continuum hypothesis on the basis of a newly discovered fundamental principle of set theory, a missing axiom, widely regarded as true. Such a dream solution would indeed be a solution, since we would all accept the new axiom along with its consequences. In this article, however, I argue that such a dream solution to $\mathrm {CH}$ is unattainable.

The theoretical foundations of climate science have received little attention from philosophers thus far, despite a number of outstanding issues. We provide a brief, non-technical overview of several of these issues – related to theorizing about climates, climate change, internal variability and more – and attempt to make preliminary progress in addressing some of them. In doing so, we hope to open a new thread of discussion in the emerging area of philosophy of climate science, focused on theoretical foundations.

Biologists and historians often present natural history and molecular biology as distinct, perhaps conflicting, fields in biological research. Such accounts, although supported by abundant evidence, overlook important areas of overlap between these areas. Focusing upon examples drawn particularly from systematics and molecular evolution, I argue that naturalists and molecular biologists often share questions, methods, and forms of explanation. Acknowledging these interdisciplinary efforts provides a more balanced account of the development of biology during the post-World War II era.

“Intervention” is not synonymous with “care.” For an intervention to constitute care—which patients should have a right to access—it must be technically feasible and licit. Now these criteria do not prove sufficient; numerous archaic interventions remain feasible and legally permissible, yet are now bywords for spurious care. Therefore, we propound another necessary condition for an intervention to become care: the physician must rationally judge the intervention to be conducive to the patient’s good. Consequently, the right of access-to-care relies on physicians (...) being free to practice medicine in accord with their consciences, conscience being the rational faculty with which they judge the reasonableness of even mundane medical decisions. Since physicians operate as part of a community, it is further necessary to consider when central bodies may reasonably compel physicians to engage in interventions that the physician believes are not consistent with the patient’s good and/or are not congruent with the purposes of medicine. (shrink)

We introduce the resurrection axioms, a new class of forcing axioms, and the uplifting cardinals, a new large cardinal notion, and prove that various instances of the resurrection axioms are equiconsistent over ZFC with the existence of an uplifting cardinal.

Vers la fin du XIVe siècle se fait jour une théorie du signe et de la signification qui, par une réélaboration des principaux concepts sémantiques, renouvelle toute l’analyse logique du langage.Partant de Guillaume d’Ockham, dont l’œuvre est ici décisive, cet ouvrage suit le développement d’une logique fondée sur des éléments de sémiologie, à travers différents auteurs du XIVe siècle tels que Gauthier Burley, Jean Buridan, Albert de Saxe, Marsile d’Inghen, Pierre d’Ailly...Une telle « logique du signe » prend place dans (...) toute une mutation du savoir, en ce siècle où la crise profonde du monde médiéval appelle une autre conception des rapports entre l’homme, les choses extérieures et le langage. (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.

We introduce the $\Sigma _1$ -definable universal finite sequence and prove that it exhibits the universal extension property amongst the countable models of set theory under end-extension. That is, the sequence is $\Sigma _1$ -definable and provably finite; the sequence is empty in transitive models; and if M is a countable model of set theory in which the sequence is s and t is any finite extension of s in this model, then there is an end-extension of M to a (...) model in which the sequence is t. Our proof method grows out of a new infinitary-logic-free proof of the Barwise extension theorem, by which any countable model of set theory is end-extended to a model of $V=L$ or indeed any theory true in a suitable submodel of the original model. The main theorem settles the modal logic of end-extensional potentialism, showing that the potentialist validities of the models of set theory under end-extensions are exactly the assertions of S4. Finally, we introduce the end-extensional maximality principle, which asserts that every possibly necessary sentence is already true, and show that every countable model extends to a model satisfying it. (shrink)

This volume brings together a collection of essays that explore in a new way how unacknowledged moral concerns are integral to debates in the philosophy of mind.The radical suggestion of the book is that we can make sense of the internal dynamics and cultural significance of these debates only when we understand the moral forces that shape them. Drawing inspiration from a variety of traditions including Wittgenstein, Lacan, phenomenology and analytic philosophy, the authors address a wide range of topics including (...) the mind/body-problem, the problem of other minds, subjectivity and objectivity, the debates on mindreading, naturalism, reductive physicalism, representationalism and the ‘E-turn’; Dennett’s heterophenomenology, McDowell’s neo-Kantianism, Wittgenstein’s ‘private language’ considerations and his notion of an ‘attitude towards a soul’; repression, love, conscience, the difficulties of self-understanding, and the methods and aims of philosophy. Through a combination of detailed, immanent criticism and bold constructive work, the authors move the discussion to a new level, beyond humanistic or conservative critiques of naturalism and scientism. (shrink)

A cardinal κ is tall if for every ordinal θ there is an embedding j: V → M with critical point κ such that j > θ and Mκ ⊆ M. Every strong cardinal is tall and every strongly compact cardinal is tall, but measurable cardinals are not necessarily tall. It is relatively consistent, however, that the least measurable cardinal is tall. Nevertheless, the existence of a tall cardinal is equiconsistent with the existence of a strong cardinal. Any tall cardinal (...) κ can be made indestructible by a variety of forcing notions, including forcing that pumps up the value of 2κ as high as desired. (shrink)

In this essay, I argue that Sartre's notion of pre-reflective consciousness can be summoned to offer a general challenge to contemporary functionalist accounts of mind, broadly construed. In virtue of the challenge Sartre offers these contemporary functionalist accounts and the richness of his phenomenological analysis, I conclude that his voice needs to be included in ongoing debates over the nature of consciousness. First, I look at some of the basic claims motivating functionalist accounts of mind. Next, I look at Sartre's (...) notion of pre-reflective consciousness and discuss how this notion challenges functionalist accounts of mentality. I conclude by suggesting that Sartre's rendering of pre-reflective consciousness remains overly cognitivist. I show how this notion can be deepened to include the sensory-motor capacities of the situated body—resulting in a pre-reflective bodily self-awareness—and how this deepened formulation offers a further challenge to functionalist accounts of mind. (shrink)

A pointwise definable model is one in which every object is \loos definable without parameters. In a model of set theory, this property strengthens $V=\HOD$, but is not first-order expressible. Nevertheless, if \ZFC\ is consistent, then there are continuum many pointwise definable models of \ZFC. If there is a transitive model of \ZFC, then there are continuum many pointwise definable transitive models of \ZFC. What is more, every countable model of \ZFC\ has a class forcing extension that is pointwise definable. (...) Indeed, for the main contribution of this article, every countable model of Gödel-Bernays set theory has a pointwise definable extension, in which every set and class is first-order definable without parameters. (shrink)

Small forcing always ruins the indestructibility of an indestructible supercompact cardinal. In fact, after small forcing, any cardinal κ becomes superdestructible--any further <κ--closed forcing which adds a subset to κ will destroy the measurability, even the weak compactness, of κ. Nevertheless, after small forcing indestructible cardinals remain resurrectible, but never strongly resurrectible.

This fresh and engaging work by noted philosopher Joel Kupperman centers on "value"--in the sense of what is worth having or worthy being in life. Kupperman looks first at how judgments of values manifest themselves, whether there can be evidence for them, and whether a realistic account is appropriate. Kupperman then goes on to examine the relations between judgments of value and those of what it is best to do, and whether value has any proper role in social policy. (...) Kupperman rejects the notion that there is any one primary value, and argues instead for a pluralistic understanding of value. He contends that value must be viewed as strongly contextual; the value of a particular set of experiences in one's life can depend heavily on how they fit in or provide contrast with other elements. (shrink)

Laver [L] and others [G-S] have shown how to make the supercompactness or strongness of κ indestructible by a wide class of forcing notions. We show, alternatively, how to make these properties fragile. Specifically, we prove that it is relatively consistent that any forcing which preserves $\kappa^{<\kappa}$ and κ+, but not P(κ), destroys the measurability of κ, even if κ is initially supercompact, strong, or if I1(κ) holds. Obtained as an application of some general lifting theorems, this result is an (...) "inner model" type of theorem proved instead by forcing. (shrink)

In developing their policy on paediatric medical assistance in dying (MAID), DeMichelis, Shaul and Rapoport decide to treat euthanasia and physician-assisted suicide as ethically and practically equivalent to other end-of-life interventions, particularly palliative sedation and withdrawal of care (WOC). We highlight several flaws in the authors’ reasoning. Their argument depends on too cursory a dismissal of intention, which remains fundamental to medical ethics and law. Furthermore, they have not fairly presented the ethical analyses justifying other end-of-life decisions, analyses and decisions (...) that were generally accepted long before MAID was legal or considered ethical. Forgetting or misunderstanding the analyses would naturally lead one to think MAID and other end-of-life decisions are morally equivalent. Yet as we recall these well-developed analyses, it becomes clear that approving of some forms of sedation and WOC does not commit one to MAID. Paediatric patients and their families can rationally and coherently reject MAID while choosing palliative care and WOC. Finally, the authors do not substantiate their claim that MAID is like palliative care in that it alleviates suffering. It is thus unreasonable to use this supposition as a warrant for their proposed policy. (shrink)

Beginning in the mid-1930s the comparative physiologists Laurence Irving and Per Fredrik Scholander pioneered the study of diving mammals, particularly harbor seals. Although resting on earlier work dating back to the late nineteenth century, their research was distinctive in several ways. In contrast to medically oriented physiology, the approaches of Irving and Scholander were strongly influenced by natural history, zoology, ecology, and evolutionary biology. Diving mammals, they argued, shared the cardiopulmonary physiology of terrestrial mammals, but evolution had modified these basic (...) adaptive processes in extreme ways. In particular, seals’ remarkable ability to hold breath, lower metabolism, produce energy anaerobically, and resist asphyxiation, provided a sharp contrast with terrestrial mammals, including humans. This diving physiology was an extreme elaboration of a general regulatory mechanism that allowed seals and other diving mammals to remain active underwater for extended periods. The decrease in heart rate referred to as bradycardia or the “diving reflex” was highly developed in diving mammals, but also found in less developed form in many other organisms faced by asphyxia. It therefore served as a kind of “master switch” for lowering metabolism in diving, hibernation, parturition, drowning, and other physiological responses involving lack of oxygen. Studying bradycardia unified a wide diversity of physiological phenomena, while also providing a context for contrasting the physiological responses of various species, including humans. Conducted in the laboratory and the field, this research served as a bridge between a comparative physiological ecology focused on non-human species and a human-centered general physiology. (shrink)

Applying the seed concept to Prikry tree forcing P μ , I investigate how well P μ preserves the maximality property of ordinary Prikry forcing and prove that P μ Prikry sequences are maximal exactly when μ admits no non-canonical seeds via a finite iteration. In particular, I conclude that if μ is a strongly normal supercompactness measure, then P μ Prikry sequences are maximal, thereby proving, for a large class of measures, a conjecture of W. Hugh Woodin's.

We consider a set-theoretic version of mereology based on the inclusion relation ⊆ and analyze how well it might serve as a foundation of mathematics. After establishing the non-definability of ∈ from ⊆, we identify the natural axioms for ⊆-based mereology, which constitute a finitely axiomatizable, complete, decidable theory. Ultimately, for these reasons, we conclude that this form of set-theoretic mereology cannot by itself serve as a foundation of mathematics. Meanwhile, augmented forms of set-theoretic mereology, such as that obtained by (...) adding the singleton operator, are foundationally robust. (shrink)

The Necessary Maximality Principle for c. c. c. forcing with real parameters is equiconsistent with the existence of a weakly compact cardinal. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim).

Ecology has often been characterized as an immature scientific discipline. This paper explores some of the sources of this alleged immaturity. I argue that the perception of immaturity results primarily from the fact that historically ecologists have based their work upon two very different approaches to research.

Corporations have scrambled to bring to market products positioned and advertised as addressing the needs of the environmentally-conscious consumer. The vast majority of claims presented in support of these products are best described, however, as confused, misleading or outright illegal. Ethical considerations have not yet been integrated into environmental marketing, and as a result, long-term harm on both the individual and societal level may result. A framework for reversing this trend is presented. It identifies the sequence of actions necessary for (...) the development and communication of ethical environmental marketing claims. The sequence is based upon two aspects of ethical theory: moral style and normative behavior. Specific implications for marketers'' actions at each stage in the sequence of framework development are also discussed. (shrink)

The phylogenetic species concept is applied for the first time to a major radiation of birds, the birds-of-paradise (Paradisaeidae) of Australasia. Using the biological species concept, previous workers have postulated approximately 40–42 species in the family. Of these, approximately 13 are monotypic and 27 are polytypic with about 100 subspecies. Phylogenetic species are irreducible (basal) clusters of organisms (terminal taxa) that are diagnosably distinct from other such clusters. Within the context of this concept, approximately 90 species of paradisaeids are postulated (...) to have diversified within Australasia. The phylogenetic species concept more accurately describes evolutionary diversity within the family and provides a better theoretical and empirical framework for analysing speciation, historical biogeography and patterns of morphological, behavioral and ecological diversification within this group than does the biological species concept. (shrink)

Among the topics discussed in Thomas Kuhn'sThe Structure of Scientific Revolutions, those of education, training, and pedagogy are apt to seem the least compelling. Certainly, the earliest debates aboutStructurefocused on other, more controversial, matters: incommensurability, meaning change, the rationality of theory choice, normal science—the list goes on. Over the past two decades, however, a growing concern among historians and sociologists of science with the nature of scientific apprenticeship has stimulated greater appreciation of the importance of questions of teaching and learning (...) to the philosophical position sketched inStructure. This paper seeks to develop further our understanding of these issues as they bear on Kuhn's theory of science. (shrink)

We introduce the strongly uplifting cardinals, which are equivalently characterized, we prove, as the superstrongly unfoldable cardinals and also as the almost-hugely unfoldable cardinals, and we show that their existence is equiconsistent over ZFC with natural instances of the boldface resurrection axiom, such as the boldface resurrection axiom for proper forcing.

This essay argues that post-analytic philosophy finds its origins not only in an invented tradition—that of ‘analytic philosophy’—but also in an invented dilemma: namely, the response to the allegedly overweening dominance of ‘positivism’ in American philosophy. I begin by surveying the problems with the folk wisdom about positivism and analytic philosophy. This pervasive narrative locates the emergence of post-analytic philosophy after a period of hegemony for logical positivism and cognate philosophical subfields. Taking seriously evidence indicating a distinct overlap in the (...) construction of the analytic and post-analytic traditions, I return to the founding moment of American analytic philosophy in the years immediately following World War II. What we see, I suggest, is not a reaction against a clearly defined and powerful logical positivist mainstream, but the careful, piecewise co-ordination of what would become characteristic ‘analytic’ modes of argument, problematics, and tool kits. Willard Van Orman Quine played a central role in this process, and for this reason I focus on the circumstances in which his field-defining 1951 article, ‘Two Dogmas of Empiricism’ was written and received. I conclude with the claim that both analytic and post-analytic philosophers relied on a peculiar image of the failure of logical positivism, and of the opportunities that failure presented. (shrink)

During the decades following World War II diverse groups of American biologists established a variety of distinctive approaches to organismal biology. Rhetorically, organismal biology could be used defensively to distinguish established research traditions from perceived threats from newly emerging fields such as molecular biology. But, organismal biologists were also interested in integrating biological disciplines and using a focus on organisms to synthesize levels of organization from molecules and cells to populations and communities. Part of this broad movement was the development (...) of an area of research variously referred to as physiological ecology, environmental physiology, or ecophysiology. This area of research was distinctive in its self-conscious blend of field and laboratory practices and its explicit integration with other areas of biology such as ecology, animal behavior, and evolution in order to study adaptation. Comparing the intersecting careers of Knut Schmidt-Nielsen and George Bartholomew highlights two strikingly different approaches to physiological ecology. These alternative approaches to studying the interactions of organisms and environments also differed in important ways from the organismal biology championed by leading figures in the modern synthesis. (shrink)

Unfoldable cardinals are preserved by fast function forcing and the Laver-like preparations that fast functions support. These iterations show, by set-forcing over any model of ZFC, that any given unfoldable cardinal κ can be made indestructible by the forcing to add any number of Cohen subsets to κ.

The distinction between taxonomic plant geography and ecological plant geography was never absolute: it would be historically inaccurate to portray them as totally divergent. Taxonomists occasionally borrowed ecological concepts, and ecologists never completely repudiated taxonomy. Indeed, some botanists pursued the two types of geographic study. The American taxonomist Henry Allan Gleason (1882–1975), for one, made noteworthy contributions to both. Most of Gleason's research appeared in short articles, however. He never published a major synthetic work comparable in scope or influence to (...) the ecological texts of Clements, Schimper, and Warming.Despite exceptions such as Gleason, most plant geographers throughout the twentieth century have emphasized the distinction between ecological and taxonomic plant geographies. Why have these distinct traditions developed? In his book Geographical Ecology, Robert MacArthur has suggested a psychological explanation for the dichotomy: “Unraveling the history of a phenemenon has always appealed to some people and describing the machinery of the phenomenon to others... The ecologist and physical scientist tend to be machinery oriented, whereas paleontologists and most biogeographers tend to be history oriented.”46Without necessarily rejecting MacArthur's explanation, my study suggests a more complex relationship between taxonomic and ecological plant geographies. At the turn of the century a group of botanists self-consciously defined a new area of botanical research. These ecologists defined their new discipline in opposition to what they believed was a moribund, nineteenth-century, natural-history tradition. They turned from historically oriented, descriptive, taxonomic plant geography to experimental physiology. The new ecological plant geography was to focus on communities rather than on species, on proximate environmental causes rather than on historical explanations, and on physiological experiments rather than on morphological descriptions.As we look back, much of the “revolt from morphology” was rhetorical. Ecologists never completely replaced species as units of distribution, nor did they set geography on an explicitly physiological basis. Indeed, much of early ecological research was, quite simply, descriptive. Plant communities were defined in terms of dominant species, representative life forms, or general physiognomy. The underlying physiological basis for community characteristics was more often assumed than demonstrated by experiments.Despite the fact that ecological plant geography was not a truly physiological specialty, it was significantly different from more traditional taxonomic plant geography. First, ecologists were less explicitly evolutionary in their approach than were taxonomists. Following Darwin, most taxonomic plant geographers viewed distribution in historical terms. In contrast, early ecologists tended to ignore the traditional geographic problems. Most ecologists were skeptical of historical explanations, emphasizing instead the proximate, environmental causes of distribution. While some nineteenth-century biogeographers had studied the correlation between climate and vegetation, twentieth-century ecologists focused much more sharply on the interactions between plant and environment. Plant ecologists did not place biogeography on a physiological basis, but by emphasizing physiology they laid the foundation for a more detailed understanding of adaption. This emphasis on physiology and environmental causation was a second distinguishing characteristic of ecological plant geography. Finally, the idea of the plant community, articulated by Eugenius Warming in 1895, provided ecologists with a unique perspective on the distribution of plants. For early ecologists, the community was more than an assemblage of species; it was an integrated unit. The distribution of these units became the major focus of ecological plant geography. Communities never completely replaced species as geographic units, and the distinction between flora and vegetation was often blurred. Nonetheless, ecologists were innovative in studying the distribution of structurally and functionally integrated groups of plants.In the twentieth century plant geography has occupied an anomalous position in biology. It has not developed into an autonomous discipline, nor has it been incorporated into the developing discipline of ecology. Ecologists and taxonomists have pursued fairly distinct styles of geographic research, with the result that two relatively independent approaches to the study of plant distribution have persisted. (shrink)