This contribution to part 4 of the Common Knowledge symposium “Fuzzy Studies: On the Consequence of Blur” shows how the reputedly radical position that history is not about eternal truths but about the creative construction of a convincing narrative of past events is not an argument of recent vintage. In the days when postmodernism was a technical term used mainly by scholars of art and architecture—and indeed, decades before then—professional historians were grappling with the incapacity of facts to write themselves (...) into a universally satisfying, single version of history. Successive presidents of the American Historical Association such as Andrew Dickson White, Carl Becker, Charles Beard, and William McNeill admitted that writing history is a desperate attempt at pattern recognition in a fuzzy discipline. Pattern recognition is a tool, valuable as a stage in historical thinking, but destined ultimately to come undone. What remains, then, is fuzzy thinking. It can be a good thing, the article concludes, to let our thinking about history remain a blur or, at least, to bear in mind that any patterns we recognize in the past are liable to dissolve under a different light. (shrink)

The essays in this volume are a contribution to this process of reappraisal, focusing specifically on the phenomena of scepticism and millenarianism, especially ...

This latest book, whose editors were among those who prepared the first two volumes, centers on Popkin's crucial role in bringing together scholars from around ...

RAID-II is a high-bandwidth, network-attached storage server designed and implemented at the University of California at Berkeley. In this paper, we measure the performance of RAID-II and evaluate various architectural decisions made during the design process. We first measure the end-to-end performance of the system to be approximately 20 MB/s for both disk array reads and writes. We then perform a bottleneck analysis by examining the performance of each individual subsystem and conclude that the disk subsystem limits performance. By adding (...) a custom interconnect board with a high-speed memory and bus system and parity engine, we are able to achieve a performance speedup of 8 to 15 over a comparative system using only off-the-shelf hardware. (shrink)

Abraham Robinson’s framework for modern infinitesimals was developed half a century ago. It enables a re-evaluation of the procedures of the pioneers of mathematical analysis. Their procedures have been often viewed through the lens of the success of the Weierstrassian foundations. We propose a view without passing through the lens, by means of proxies for such procedures in the modern theory of infinitesimals. The real accomplishments of calculus and analysis had been based primarily on the elaboration of novel techniques for (...) solving problems rather than a quest for ultimate foundations. It may be hopeless to interpret historical foundations in terms of a punctiform continuum, but arguably it is possible to interpret historical techniques and procedures in terms of modern ones. Our proposed formalisations do not mean that Fermat, Gregory, Leibniz, Euler, and Cauchy were pre-Robinsonians, but rather indicate that Robinson’s framework is more helpful in understanding their procedures than a Weierstrassian framework. (shrink)

In relation to a thesis put forward by Marx Wartofsky, we seek to show that a historiography of mathematics requires an analysis of the ontology of the part of mathematics under scrutiny. Following Ian Hacking, we point out that in the history of mathematics the amount of contingency is larger than is usually thought. As a case study, we analyze the historians’ approach to interpreting James Gregory’s expression ultimate terms in his paper attempting to prove the irrationality of \. Here (...) Gregory referred to the last or ultimate terms of a series. More broadly, we analyze the following questions: which modern framework is more appropriate for interpreting the procedures at work in texts from the early history of infinitesimal analysis? As well as the related question: what is a logical theory that is close to something early modern mathematicians could have used when studying infinite series and quadrature problems? We argue that what has been routinely viewed from the viewpoint of classical analysis as an example of an “unrigorous” practice, in fact finds close procedural proxies in modern infinitesimal theories. We analyze a mix of social and religious reasons that had led to the suppression of both the religious order of Gregory’s teacher degli Angeli, and Gregory’s books at Venice, in the late 1660s. (shrink)

Humanist sociologists are activists rooted in the reality of history and change and guided by a concern for the 'real life' problems of equality, peace, and social justice. They view people as active shapers of social life, capable of creating societies in which everyone's potential can unfold. Alfred McClung Lee introduces this volume with 'Sociology: Humanist and Scientific' and develops the theme that a sociology that is humanist is also scientific. The other nine selections are grouped into four parts: 'The (...) Individual and Social Life;' 'Social Institutions: Technology, Science, and Formal Organization;' 'Political Structures: Issues of Justice and Equality;' and 'Methodological Critiques and Counterproposals.'. (shrink)

For at least the past 15 years, food safety stakeholders across all levels of government have recognized the critical role that state and local agencies play in our nation's food safety system. State and local agencies are the first responders to foodborne outbreaks and have primary responsibility for keeping their residents safe from foodborne disease through effective surveillance and rapid response to outbreaks. They also conduct the vast majority of food safety inspections across the nation's restaurants, grocery stores, and other (...) food service and food retail establishments.Recent efforts among industry and government officials alike have focused on creating a more integrated, prevention-oriented food safety system. The Food Safety Modernization Act, the first major overhaul of the nation's food safety laws since the 1930s, now mandates that most sectors of the food industry put preventive controls in place, changing the emphasis of what the FDA does from response to prevention. (shrink)

Cauchy's sum theorem is a prototype of what is today a basic result on the convergence of a series of functions in undergraduate analysis. We seek to interpret Cauchy’s proof, and discuss the related epistemological questions involved in comparing distinct interpretive paradigms. Cauchy’s proof is often interpreted in the modern framework of a Weierstrassian paradigm. We analyze Cauchy’s proof closely and show that it finds closer proxies in a different modern framework.

We apply Benacerraf’s distinction between mathematical ontology and mathematical practice to examine contrasting interpretations of infinitesimal mathematics of the seventeenth and eighteenth century, in the work of Bos, Ferraro, Laugwitz, and others. We detect Weierstrass’s ghost behind some of the received historiography on Euler’s infinitesimal mathematics, as when Ferraro proposes to understand Euler in terms of a Weierstrassian notion of limit and Fraser declares classical analysis to be a “primary point of reference for understanding the eighteenth-century theories.” Meanwhile, scholars like (...) Bos and Laugwitz seek to explore Eulerian methodology, practice, and procedures in a way more faithful to Euler’s own. Euler’s use of infinite integers and the associated infinite products are analyzed in the context of his infinite product decomposition for the sine function. Euler’s principle of cancellation is compared to the Leibnizian transcendental law of homogeneity. The Leibnizian law of continuity similarly finds echoes in Euler. We argue that Ferraro’s assumption that Euler worked with a classical notion of quantity is symptomatic of a post-Weierstrassian placement of Euler in the Archimedean track for the development of analysis, as well as a blurring of the distinction between the dual tracks noted by Bos. Interpreting Euler in an Archimedean conceptual framework obscures important aspects of Euler’s work. Such a framework is profitably replaced by a syntactically more versatile modern infinitesimal framework that provides better proxies for his inferential moves. (shrink)

Foundations of Science recently published a rebuttal to a portion of our essay it published 2 years ago. The author, G. Schubring, argues that our 2013 text treated unfairly his 2005 book, Conflicts between generalization, rigor, and intuition. He further argues that our attempt to show that Cauchy is part of a long infinitesimalist tradition confuses text with context and thereby misunderstands the significance of Cauchy’s use of infinitesimals. Here we defend our original analysis of various misconceptions and misinterpretations concerning (...) the history of infinitesimals and, in particular, the role of infinitesimals in Cauchy’s mathematics. We show that Schubring misinterprets Proclus, Leibniz, and Klein on non-Archimedean issues, ignores the Jesuit context of Moigno’s flawed critique of infinitesimals, and misrepresents, to the point of caricature, the pioneering Cauchy scholarship of D. Laugwitz. (shrink)

We examine Paul Halmos’ comments on category theory, Dedekind cuts, devil worship, logic, and Robinson’s infinitesimals. Halmos’ scepticism about category theory derives from his philosophical position of naive set-theoretic realism. In the words of an MAA biography, Halmos thought that mathematics is “certainty” and “architecture” yet 20th century logic teaches us is that mathematics is full of uncertainty or more precisely incompleteness. If the term architecture meant to imply that mathematics is one great solid castle, then modern logic tends to (...) teach us the opposite lesson, namely that the castle is floating in midair. Halmos’ realism tends to color his judgment of purely scientific aspects of logic and the way it is practiced and applied. He often expressed distaste for nonstandard models, and made a sustained effort to eliminate first-order logic, the logicians’ concept of interpretation, and the syntactic vs semantic distinction. He felt that these were vague, and sought to replace them all by his polyadic algebra. Halmos claimed that Robinson’s framework is “unnecessary” but Henson and Keisler argue that Robinson’s framework allows one to dig deeper into set-theoretic resources than is common in Archimedean mathematics. This can potentially prove theorems not accessible by standard methods, undermining Halmos’ criticisms. (shrink)

Worldwide, the COVID-19 pandemic has forced people to adapt quickly, and to reexamine interactions and responsibilities toward communities in creative ways. This paper presents a qualitative media analysis of 50 online news articles published between March 17th and August 6th, 2020 using the key-words “creativity” and “COVID-19.” Informed by a definition of creativity as actions that are considered both “new” and “appropriate”, articles describing a “creative action” were kept for analysis. These articles highlight creative responses to the COVID-19 quarantine in (...) various domains including architecture, fashion, and faith. In this paper, we discuss the themes derived during this analysis- “renewal and continuity” and “the multidimensionality of creativity” which elaborate and contextualize a perspective of socio-cultural creativity theory and propose two implications of this study. The first implication posits that creativity was an observable, cultural response to the COVID-19 pandemic. The second implication offers a broader concept of how cultural resources function as dynamic constraints or “affordances” within the Five A’s model of creativity. Discussion of further research through the lens of socio-cultural creativity is discussed. (shrink)

The first half of the 17th century was a time of intellectual ferment when wars of natural philosophy were echoes of religious wars, as we illustrate by a case study of an apparently innocuous mathematical technique called adequality pioneered by the honorable judge Pierre de Fermat, its relation to indivisibles, as well as to other hocus-pocus. André Weil noted that simple applications of adequality involving polynomials can be treated purely algebraically but more general problems like the cycloid curve cannot be (...) so treated and involve additional tools–leading the mathematician Fermat potentially into troubled waters. Breger attacks Tannery for tampering with Fermat’s manuscript but it is Breger who tampers with Fermat’s procedure by moving all terms to the left-hand side so as to accord better with Breger’s own interpretation emphasizing the double root idea. We provide modern proxies for Fermat’s procedures in terms of relations of infinite proximity as well as the standard part function. (shrink)

Adequality, or παρισóτης (parisotēs) in the original Greek of Diophantus 1 , is a crucial step in Fermat’s method of finding maxima, minima, tangents, and solving other problems that a modern mathematician would solve using infinitesimal calculus. The method is presented in a series of short articles in Fermat’s collected works (1891, pp. 133–172). The first article, Methodus ad Disquirendam Maximam et Minimam 2 , opens with a summary of an algorithm for finding the maximum or minimum value of an (...) algebraic expression in a variable A. For convenience, we will write such an expression in modern functional notation as f (a). 3 The algorithm can be broken up into six steps in the following way:Introduce an auxiliary .. (shrink)

The philosophy of deep ecology originated in the 1970s with the Norwegian philosopher Arne Naess and has since spread around the world. Its basic premises are a belief in the intrinsic value of nonhuman nature, a belief that ecological principles should dictate human actions and moral evaluations, an emphasis on noninterference into natural processes, and a critique of materialism and technological progress.This book approaches deep ecology as a philosophy, not as a political, social, or environmental movement. In part I, the (...) authors compare deep ecology's philosophical ideas with other positions and debates in environmental philosophy and to other schools of thought such as social ecology, ecofeminism, and moral pluralism. In part II, they investigate the connections between deep ecology and other contemporary world views, such as continental philosophy, postmodernism, and non-Western philosophical traditions. The first anthology on deep ecology that is not primarily the work of the movement's followers, Beneath the Surface offers a rigorous assessment of deep ecology's strengths and weaknesses as a philosophical position.Contributors : John Clark, Deane Curtin, Arran Gare, William Grey, Mathew Humphrey, Knut Jacobsen, Eric Katz, Andrew Light, Jonathan Maskit, Val Plumwood, David Rothenberg, Ariel Salleh, Bron Taylor, Michael Zimmerman. (shrink)

The Dirac δ function has solid roots in nineteenth century work in Fourier analysis and singular integrals by Cauchy and others, anticipating Dirac’s discovery by over a century, and illuminating the nature of Cauchy’s infinitesimals and his infinitesimal definition of δ.

Many historians of the calculus deny significant continuity between infinitesimal calculus of the seventeenth century and twentieth century developments such as Robinson’s theory. Robinson’s hyperreals, while providing a consistent theory of infinitesimals, require the resources of modern logic; thus many commentators are comfortable denying a historical continuity. A notable exception is Robinson himself, whose identification with the Leibnizian tradition inspired Lakatos, Laugwitz, and others to consider the history of the infinitesimal in a more favorable light. Inspite of his Leibnizian sympathies, (...) Robinson regards Berkeley’s criticisms of the infinitesimal calculus as aptly demonstrating the inconsistency of reasoning with historical infinitesimal magnitudes. We argue that Robinson, among others, overestimates the force of Berkeley’s criticisms, by underestimating the mathematical and philosophical resources available to Leibniz. Leibniz’s infinitesimals are fictions, not logical fictions, as Ishiguro proposed, but rather pure fictions, like imaginaries, which are not eliminable by some syncategorematic paraphrase. We argue that Leibniz’s defense of infinitesimals is more firmly grounded than Berkeley’s criticism thereof. We show, moreover, that Leibniz’s system for differential calculus was free of logical fallacies. Our argument strengthens the conception of modern infinitesimals as a development of Leibniz’s strategy of relating inassignable to assignable quantities by means of his transcendental law of homogeneity. (shrink)

I develop and defend a hedonistic view of the constitution of human subjectivity, agency and value, while disassociating it from utilitarian accounts of morality and from the view that only pleasure is desired. Chapter One motivates the general question, "What really is of value in human living?", and introduces evaluative hedonism as an answer to this question. Chapter Two argues against preference satisfaction accounts of pleasure and of welfare, and begins the explication and defense of the hedonist's conception of pleasure (...) as immediate experiencing liked for its own sake in its experiential moment, and which obtains or not in an experiential moment regardless of what obtains at other times. Chapter Three begins the task of finding a motivational theory that will support, or at least cohere with, evaluative hedonism. I here work toward my own position by discussing, criticizing and distinguishing some aspects of the views of earlier hedonistic writers, both ancient and modern. Chapter Four further explains the hedonist's conception of pleasure, and treats some contextualist objections to its tenability suggested by Plato, Moore and Anscombe. In the course of answering these objections, the view of consciousness belonging to the hedonist's view of mind is contrasted with that which the objections presuppose. Chapter Five first outlines the general kind of hedonistic view resulting from the work of the earlier sections, and then develops a specific view of this kind, drawing on contemporary work in philosophy, psychology and psychobiology. The result is an account of action, and of the kind of attention and consciousness connected with it, in which pleasure has a central organizing role. Such an account, if sustained and filled out by ongoing scientific work, would further motivate, and cohere with, evaluative hedonism and the related contention that the dimension of subjectivity in which human value consists is in the lives of human beings and other higher vertebrates much the same. (shrink)

In his 1676 text De Quadratura Arithmetica, Leibniz distinguished infinita terminata from infinita interminata. The text also deals with the notion, originating with Desargues, of the point of intersection at infinite distance for parallel lines. We examine contrasting interpretations of these notions in the context of Leibniz’s analysis of asymptotes for logarithmic curves and hyperbolas. We point out difficulties that arise due to conflating these notions of infinity. As noted by Rodríguez Hurtado et al., a significant difference exists between the (...) Cartesian model of magnitudes and Leibniz’s search for a qualitative model for studying perspective, including ideal points at infinity. We show how respecting the distinction between these notions enables a consistent interpretation thereof. (shrink)

After decades of single issue movements and identity politics on the U.S. left, the series of large demonstrations beginning in 1999 in Seattle have led many to wonder if activist politics can now come together around a common theme of global justice. This book pursues the prospects for progressive political movements in the 21st century with case studies of ten representative movements, including the anti-globalization forces, environmental interest groups, and new takes on the peace movement.

Did Leibniz exploit infinitesimals and infinities à la rigueur or only as shorthand for quantified propositions that refer to ordinary Archimedean magnitudes? Hidé Ishiguro defends the latter position, which she reformulates in terms of Russellian logical fictions. Ishiguro does not explain how to reconcile this interpretation with Leibniz’s repeated assertions that infinitesimals violate the Archimedean property (i.e., Euclid’s Elements, V.4). We present textual evidence from Leibniz, as well as historical evidence from the early decades of the calculus, to undermine Ishiguro’s (...) interpretation. Leibniz frequently writes that his infinitesimals are useful fictions, and we agree, but we show that it is best not to understand them as logical fictions; instead, they are better understood as pure fictions. (shrink)

Misuse or misunderstanding of medication information is a common and costly problem in the U.S. The risks of misunderstanding medication information are compounded for the large and growing population of individuals with limited English proficiency that often lacks access to this information in their own language. This paper examines practices related to translation of medication information in the European Union that may serve as a model for future U.S. policy efforts to improve the quality and availability of medication information for (...) individuals with limited English proficiency. (shrink)

Access to clear and concise medication information is essential to support safe and effective use of prescription drugs. Patient misunderstanding of medication information is a common reason for non-adherence to medication regimens and a leading cause of outpatient medication errors and adverse drug events in the U.S. Medication errors are the most common source of risk to patient safety, leading to poor health outcomes, hospitalizations, and deaths. Over half a million adverse drug events occur in the outpatient setting each year (...) at a cost of approximately $1 billion annually.Nearly half of adults in the U.S. experience difficulty understanding and acting upon health information. Even individuals with high levels of general literacy may find medication information difficult to understand or use. The risk of misunderstanding medication information is compounded for patients with limited English proficiency who may not have access to this information in their own language. (shrink)

Four principal papers and a total of 43 peer commentaries on the evolutionary origins of morality. To what extent is human morality the outcome of a continuous development from motives, emotions and social behaviour found in nonhuman animals? Jerome Kagan, Hans Kummer, Peter Railton and others discuss the first principal paper by primatologists Jessica Flack and Frans de Waal. The second paper, by cultural anthropologist Christopher Boehm, synthesizes social science and biological evidence to support his theory of how our hominid (...) ancestors became moral. In the third paper philosopher Elliott Sober and evolutionary biologist David Sloan Wilson argue that an evolutionary understanding of human nature allows sacrifice for others and ultimate desires for another's good. Finally Brian Skyrms argues that game theory based on adaptive dynamics must join the social scientist's use of rational choice and classical game theory to explain cooperation. (shrink)

Poetry is language at its most distilled and most powerfulRita Dove(David Streitfeld, Washington Post, “Laureate for a New Age,” March 19, 1993).The genesis for this special issue arose in a rethin...

Scholars such as Renaud Barbara and Bernhard Waldenfels and Regula Giuliani have emphasized time’s central role in Merleau-Ponty’s philosophy, and Michael Kelly has shown how the Phenomenology’s “Temporality” chapter already broaches his later ontological concerns. I deepen our understanding of this temporal–ontological nexus by showing how Merleau-Ponty’s temporal ontology in fact erupts even earlier in the Phenomenology, as an underlying theme that unifies part two, on “The Perceived World,” as leading into the “Temporality” chapter. I do this via a close (...) study of the chapter, “The Thing and the Natural World,” first explicating some profound but easily overlooked points about time implied in Merleau-Ponty’s initial remarks on the constancy of form and size. I then closely analyze his study of color constancy in relation to his central source, David Katz’s The World of Colour, to show how color leads him to conceptualize things as what I call “time-things”—and more generally to conceptualize things, the world, and nature, as being in such a way that temporality is ingredient in their being. This leads to some implications for his temporal ontology. (shrink)

We propose a formal framework for interpretable machine learning. Combining elements from statistical learning, causal interventionism, and decision theory, we design an idealised explanation game in which players collaborate to find the best explanation for a given algorithmic prediction. Through an iterative procedure of questions and answers, the players establish a three-dimensional Pareto frontier that describes the optimal trade-offs between explanatory accuracy, simplicity, and relevance. Multiple rounds are played at different levels of abstraction, allowing the players to explore overlapping causal (...) patterns of variable granularity and scope. We characterise the conditions under which such a game is almost surely guaranteed to converge on a optimal explanation surface in polynomial time, and highlight obstacles that will tend to prevent the players from advancing beyond certain explanatory thresholds. The game serves a descriptive and a normative function, establishing a conceptual space in which to analyse and compare existing proposals, as well as design new and improved solutions. (shrink)

The nature of mystical experience has been hotly debated. Essentialists divide into two camps: 1) immediate identity beyond any subject-object structure 2) the mystical object maintaining some distinctness at the point of contact. Paul Tillich’s mystical a priori has some affinities with the former, while William James’ model of religious experience coheres only with the latter. Opposing the essentialists are constructivists. After noting some ironies of the constructivist position, this article elaborates difficulties with 1) the traditional model of pure identity (...) with the divine by certain mystics, 2) the Tillichian universal mystical awareness, and 3) the Jamesian direct perceptual model. Finally, it proposes that the human body and brain mediate mystical experience, which consists of a distinctive sense of bodily harmony conjoined with openness to the potentialities of an integrated environment, involving distinctive neurological processes. (shrink)

Many scholars have argued that the Protestant Reformation generally departed from virtue ethics, and this claim is often accepted by Protestant ethicists. This essay argues against such discontinuity by demonstrating John Calvin’s reception of ethical concepts from Augustine and Aristotle. Calvin drew on Augustine’s concept of eudaimonia and many aspects of Aristotle’s Nicomachean Ethics , including concepts of choice, habit, virtue as a mean, and the specific virtues of justice and prudence. Calvin also evaluated the problem of pagan virtue in (...) light of traditional Augustinian texts discussed in the medieval period. He interpreted the Decalogue as teaching virtue, including the cardinal virtues of justice and temperance. Calvin was not the harbinger of an entirely new ethical paradigm, but rather a participant in the mainstream of Christian thinkers who maintained a dual interest in Aristotelian and Augustinian eudaimonist virtue ethics. (shrink)

In this paper we criticize the commonly accepted theory of memory, and offer an alternative. According to the traditional view, memory is a stored mental representation of things past. We show, through an analysis of a single act of recognition, the logical oddities to which this view leads. Since, however, these are generally ignored, we also consider those characteristics of the traditional view which apparently make it attractive to those who hold it, namely its consonance with the commonly held conception (...) of time, its explanation for the fallibility of memory, and its way of making behavior predictable. We then present the alternative view, the direct realist theory. According to it, there is no such thing as a stored mental representation. The theory redefines memory as the perception of sequential structure, and in so doing successfully treats of the fallibility of memory and the necessity for making behavior predictable. Moreover, and perhaps most importantly, it does not lead to the logical difficulties of the traditional theory. (shrink)

In this paper, I explore connections between two disciplines not typically linked: argumentation theory and urban design. I first trace historical ties between the art of reasoned discourse and the idea of civic virtue. I next analyze discourse norms implicit in three theories of urban design: Jane Jacobs' The Death and Life of Great American Cities (1961), Christopher Alexander's A Pattern Language: Towns, Buildings, Construction (1977), and Peter Katz's The New Urbanism: Toward an Architecture of Community (1994). I then (...) propose a set of ‘settlement’ issues of potential interest to both urban designers and argumentation theorists: size, density, heterogeneity, publicity, security, and identity. I conclude by suggesting that the ‘good city’ be seen as both a spatial and a discursive entity. From such a perspective, good public discourse is dependent, at least in part, on good public space; and good public space is defined, at least in part, as a context conducive to good public discourse. (shrink)

This paper describes differences in two perspectives on the idea of virtue as a theoretical foundation for positive organizational ethics (POE). The virtue ethics perspective is grounded in the philosophical tradition, has classical roots, and focuses attention on virtue as a property of character. The positive social science perspective is a recent movement (e.g., positive psychology and positive organizational scholarship) that has implications for POE. The positive social science movement operationalizes virtue through an empirical lens that emphasizes virtuous behaviors. From (...) a virtue ethics perspective, a behaviorally based account of virtue is a weak theory of virtue. Observations are suggested for integrating the two perspectives. First, virtue should always be understood as an excellence and is often an optimal point between extreme dysfunctions on continuum of potential states. Second, an empirical exploration of virtue needs to account for character and context. Finally, the properties of organization-level virtue need to be further specified and explored. Implications and directions for future research are discussed. (shrink)

_Real Essentialism_ presents a comprehensive defence of neo-Aristotelian essentialism. Do objects have essences? Must they be the kinds of things they are in spite of the changes they undergo? Can we know what things are really like – can we define and classify reality? Many, if not most, philosophers doubt this, influenced by centuries of empiricism, and by the anti-essentialism of Wittgenstein, Quine, Popper, and other thinkers. _Real Essentialism_ reinvigorates the tradition of realist, essentialist metaphysics, defending the reality and knowability (...) of essence, the possibility of objective, immutable definition, and its relevance to contemporary scientific and metaphysical issues such as whether essence transcends physics and chemistry, the essence of life, the nature of biological species, and the nature of the person. (shrink)