Since its introduction just over two decades ago, evidence-based medicine (EBM) has come to dominate medical practice, teaching, and policy. There are a growing number of textbooks, journals, and websites dedicated to EBM research, teaching, and evidence dissemination. EBM was most recently defined as a method that integrates best research evidence with clinical expertise and patient values and circumstances in the treatment of patients. There have been debates throughout the early 21st century about what counts as good research evidence between (...) EBM proponents and philosophical critics and even within the EBM community itself. Similar controversy arises about the relative worth of patient values and clinical expertise (and how these can be integrated). EBM has also evolved in ways that have come under scrutiny. Specifically, policymakers have used EBM research methodology to increase the relative importance of clinical guidelines that some clinicians have argued are tyrannical. Philosophers have addressed all of these controversies, and with very few exceptions have been critical of EBM. In addition most philosophical attention has been on the epistemic role of Randomization and evidence hierarchies, with relatively little attention being paid to the role of Diagnosis, expertise, patient values, and Systematic Reviews within EBM. (shrink)

The purpose of this chapter is to describe what we see as several important new directions for philosophy of medicine. This recent work (i) takes existing discussions in important and promising new directions, (ii) identifies areas that have not received sufficient and deserved attention to date, and/or (iii) brings together philosophy of medicine with other areas of philosophy (including bioethics, philosophy of psychiatry, and social epistemology). To this end, the next part focuses on what we call the “epistemological turn” in (...) recent work in the philosophy of medicine; the third part addresses new developments in medical research that raise interesting questions for philosophy of medicine; the fourth part is a discussion of philosophical issues within the practice of diagnosis; the fifth part focuses on the recent developments in psychiatric classification and scientific and ethical issues therein, and the final part focuses on the objectivity of medical research. (shrink)

Mark Colyvan formulates a puzzle about belief in inconsistent entities. As a scientific realist, Colyvan refers to salient instances of inconsistencies in our best science and demonstrates how an indispensability argument may justify belief in an inconsistent entity. Colyvan’s indispensability argument presents a two-horned dilemma: either scientific realists are committed to the possibility of warranted belief in inconsistent objects, or we have a reductio ad absurdum, bringing realism into a crisis. Firstly, this paper follows Graham Priest by opposing the (...) received characterisation of inconsistent belief as a kind of epistemic hell. Secondly, I challenge the Quinean naturalism that underpins Colyvan’s indispensability argument. Then, I reformulate Colyvan’s argument with a fallible naturalism, better equipped to account for certain problem candidates for inconsistent entities. Finally, I contend that—even if indispensable—an inconsistent entity poses no problem for the scientific realist, who can have justified belief in inconsistent entities. (shrink)

The norm of assertion, to be in force, is a social norm. What is the content of our social norm of assertion? Various linguistic arguments purport to show that to assert is to represent oneself as knowing. But to represent oneself as knowing does not entail that assertion is governed by a knowledge norm. At best these linguistic arguments provide indirect support for a knowledge norm. Furthermore, there are alternative, non-normative explanations for the linguistic data (as in recent work from (...) Van Elswyk). Direct arguments would rely on normative judgments about the permissibility or impermissibility of assertions with and without the speaker knowing the content asserted. John Turri's work experimental results purport to show that our norm of assertion is factive, and probably knowledge. But as a number of recent experimentalists (Kneer, Reuter and Broessel, Marsili and Wiegmann) have shown, Turri's results rely on the problemmatic use of 'should' as in 'Maria should assert that she owns a 1990 watch.' Correcting for this, these experimentalists provide strong evidence that our norm of assertion is not factive. The standard reply to evidence like this from the assertion of unlucky falsehoods is the excuse maneuver. But Marsili and Wiegmann, following Turri's protocol for testing for excuse validation, show that participants who judge that assertions unlucky falsehoods are permissible are not guilty of excuse validation. Given our current understanding of the experimental evidence, knowledge is not our norm of assertion. (shrink)

This introduction provides brief outlines of the articles collected in this special issue of the International Journal of Philosophical Studies on the topic of Ethics and Emotions. It also announces the winners of the 2021 Robert Papazian and PERITIA prizes.

What is the biological function of perception? I hold perception, especially visual perception in humans, has the biological function of accurately representing the environment. Tyler Burge argues this cannot be so in Origins of Objectivity (Oxford, 2010), for accuracy is a semantical relationship and not, as such, a practical matter. Burge also provides a supporting example. I rebut the argument and the example. Accuracy is sometimes also a practical matter if accuracy partly explains how perception contributes to survival and reproduction.

According to the powerful qualities view, properties are both powerful and qualitative. Indeed, on this view the powerfulness of a property is identical to its qualitativity. Proponents claim that this view provides an attractive alternative to both the view that properties are pure powers and the view that they are pure qualities. It remains unclear, however, whether the claimed identity between powerfulness and qualitativity can be made coherent in a way that allows the powerful qualities view to constitute this sort (...) of alternative. I argue here that this can be done, given a particular conception of both the qualitativity and powerfulness of properties. On this conception, a property is qualitative just in the sense that its essence is fixed independently of any distinct properties, and it is powerful just if its essence grounds its dispositional role. (shrink)

I defend a new account of constitutive essence on which an entity’s constitutively essential properties are its most fundamental, nontrivial necessary properties. I argue that this account accommodates the Finean counterexamples to classic modalism about essence, provides an independently plausible account of constitutive essence, and does not run into clear counterexamples. I conclude that this theory provides a promising way forward for attempts to produce an adequate nonprimitivist, modalist account of essence. As both triviality and fundamentality in the account are (...) understood in terms of grounding, the theory also potentially has important implications for the relation between essence and grounding. (shrink)

Understanding everyday behavior relies heavily upon understanding our ability to improvise, how we are able to continuously anticipate and adapt in order to coordinate with our environment and others. Here we consider the ability of musicians to improvise, where they must spontaneously coordinate their actions with co-performers in order to produce novel musical expressions. Investigations of this behavior have traditionally focused on describing the organization of cognitive structures. The focus, here, however, is on the ability of the time-evolving patterns of (...) inter-musician movement coordination as revealed by the mathematical tools of complex dynamical systems to provide a new understanding of what potentiates the novelty of spontaneous musical action. We demonstrate this approach through the application of cross wavelet spectral analysis, which isolates the strength and patterning of the behavioral coordination that occurs between improvising musicians across a range of nested time-scales. Revealing the sophistication of the previously unexplored dynamics of movement coordination between improvising musicians is an important step towards understanding how creative musical expressions emerge from the spontaneous coordination of multiple musical bodies. (shrink)

Discussions about the nature of essence and about the inference problem for non-Humean theories of nomic modality have largely proceeded independently of each other. In this article I argue that the right conclusions to draw about the inference problem actually depend significantly on how best to understand the nature of essence. In particular, I argue that this conclusion holds for the version of the inference problem developed and defended by Alexander Bird. I argue that Bird’s own argument that this problem (...) is fatal for David Armstrong’s influential theory of the laws of nature but not for dispositional essentialism is seriously flawed. In place of this argument, I develop an argument that whether Bird’s inference problem raises serious difficulties for Armstrong’s theory depends on the answers to substantial questions about how best to understand essence. The key consequence is that considerations about the nature of essence have significant, underappreciated implications for Armstrong’s theory. (shrink)

While the inference problem is widely thought to be one of the most serious problems facing non-Humean accounts of laws, Jonathan Schaffer has argued that a primitivist response straightforwardly dissolves the problem. On this basis, he claims that the inference problem is really a pseudo-problem. Here I clarify the prospects of a primitivist response to the inference problem and their implications for the philosophical significance of the problem. I argue both that it is a substantial question whether this sort of (...) response ought to be accepted and that the inference problem, contra Schaffer, remains a significant problem with important implications for the non-Humean position. I also argue that this discussion indicates grounds to be wary about applying the Schaffer-style strategy of straightforwardly dissolving problems by stipulation to other philosophical problems. (shrink)

It is often taken for granted that our desires can contribute to what it is rational for us to do. This paper examines an account of desire—the ‘guise of the good’— that promises an explanation of this datum. I argue that extant guise-of-the-good accounts fail to provide an adequate explanation of how a class of desires—basic desires—contributes to practical rationality. I develop an alternative guise-of-the-good account on which basic desires attune us to our reasons for action in virtue of their (...) biological function. This account emphasises the role of desire as part of our competence to recognise and respond to normative reasons. (shrink)

This paper argues for the general proper functionalist view that epistemic warrant consists in the normal functioning of the belief-forming process when the process has forming true beliefs reliably as an etiological function. Such a process is reliable in normal conditions when functioning normally. This paper applies this view to so-called testimony-based beliefs. It argues that when a hearer forms a comprehension-based belief that P (a belief based on taking another to have asserted that P) through the exercise of a (...) reliable competence to comprehend and filter assertive speech acts, then the hearer's belief is prima facie warranted. The paper discusses the psychology of comprehension, the function of assertion, and the evolution of filtering mechanisms, especially coherence checking. (shrink)

Many philosophers have suggested that claims of need play a special normative role in ethical thought and talk. But what do such claims mean? What does this special role amount to? Progress on these questions can be made by attending to a puzzle concerning some linguistic differences between two types of 'need' sentence: one where 'need' occurs as a verb, and where it occurs as a noun. I argue that the resources developed to solve the puzzle advance our understanding of (...) the metaphysics of need, the meaning of 'need' sentences, and the function of claims of need in ethical discourse. (shrink)

According to a well-known argument against dispositional essentialism, the nature of unmanifested token powers leaves dispositional essentialists with an objectionable commitment to the reality of non-existent entities. The idea is that, because unmanifested token powers are directed at their non-existent token manifestations, they require the reality of those manifestations. Arguably the most promising response to this argument works by claiming that, if properties are universals, dispositional directedness need only entail the reality of actually existing manifestation types. I argue that this (...) response fails, because no version of the response can adequately accommodate dispositions of the sort that follow from Coulomb’s law. This result both defeats an important argument that dispositional essentialists ought to be realists about universals and appears to leave dispositional essentialists with a problematic commitment to either non-relational connections or a Meinongian ontology. (shrink)

Taylor has recently argued that adopting either the standard Kimian or Davidsonian approaches to the metaphysics of events quite directly solves the regress of pure powers. I argue, though, that on closer inspection Taylor’s proposal does not succeed, given either the Kimian or the Davidsonian account of events.

Hylomorphism is the Aristotelian theory according to which substances are composites of matter and form. If my house is a substance, then its matter would be a collection of bricks and timbers and its form something like a structure that unites those bricks and timbers into a single substance. Contemporary hylomorphists are divided on how to understand forms best, but a prominent group of theorists argue that forms are emergent powers. According to such views, when material components are arranged appropriately, (...) a novel substance emerges with the power to impose unity on its components through time. I argue that these accounts of form fall prey to a bootstrapping problem, and so, suffer from issues of redundancy, given plausible assumptions about inherence. In their place, I suggest an ontologically minimalist conception of forms as collective manifestations of the powers of matter. (shrink)

Experiences of urges, impulses, or inclinations are among the most basic elements in the practical life of conscious agents. This article develops a theory of urges and their epistemology. The article motivates a tripartite framework that distinguishes urges, conscious experiences of urges, and exercises of capacities that agents have to control their urges. The article elaborates the elements of the tripartite framework, in particular, the phenomenological contribution of motor imagery. It argues that experiences of urges and exercises of control over (...) urges play coordinate roles in enabling an agent’s awareness of their impulses. (shrink)

This paper provides a taxonomy of cosmological arguments and givesgeneral reasons for thinking that arguments that belong to a given category do not succeed.

Desire satisfaction has not received detailed philosophical examination. Yet intuitive judgments about the satisfaction of desires have been used as data points guiding theories of desire, desire content, and the semantics of ‘desire’. This paper examines desire satisfaction and the standard propositional view of desire. Firstly, I argue that there are several distinct concepts of satisfaction. Secondly, I argue that separating them defuses a difficulty for the standard view in accommodating desires that Derek Parfit described as ‘implicitly conditional on their (...) own persistence’, a problem posed by Shieva Kleinschmidt, Kris McDaniel, and Ben Bradley. The solution undercuts a key motivation for rejecting the standard view in favour of more radical accounts proposed in the literature. (shrink)

Hylomorphism is the theory that objects are composites of form and matter. Recently it has been argued that form is structure, or the arrangement of an object's parts. This paper shows that the principle of form cannot be ontologically exhausted by structure. That is, I deny form should be understood just as the arrangement of an object's parts. I do so by showing that structure cannot play the role form is supposed to in a certain domain of objects, specifically, in (...) mereological simples. Thus, I show that Hylomorphism does not reduce to Structuralism. I also draw out some important consequences from my argument for Hylomorphism in general. (shrink)

Slurring expressions display puzzling behaviour when embedded, such as under negation and in attitude and speech reports. They frequently appear to retain their characteristic qualities, like offensiveness and propensity to derogate. Yet it is sometimes possible to understand them as lacking these qualities. A theory of slurring expressions should explain this variability. We develop an explanation that deploys the linguistic notion of focus. Our proposal is that a speaker can conversationally implicate metalinguistic claims about the aptness of a focused slurring (...) expression. This explanation of variability relies on independently motivated mechanisms and is compatible with any theory of slurring expressions. (shrink)

This chapter consists of a series of reflections on widely endorsed claims about Christian philosophy and, in particular, Christian philosophy of religion. It begins with consideration of some claims about how (Christian) philosophy of religion currently is, and then moves on to consideration of some claims about how (Christian) philosophy of religion ought to be. In particular, the chapter offers critical scrutiny of the oft-repeated claim that we are currently in a golden age for Christian philosophy of religion.

It is a very curious thing that proponents of Idealism have considered it to be a satisfactory counter to ‘scepticism’, ‘nihilism’, and the like. On the contrary, it seems to me that Idealism is a very close cousin to ‘brain-in-a-vat’ scepticism and other anti-naturalistic fantasies. Moreover, it seems to me that Idealism is inferior to Naturalism for much the same kinds of reasons that ‘brain-in-a-vat’ scepticism and other anti-naturalistic fantasies are inferior to Naturalism: a proper weighing of theoretical virtues discloses (...) that Naturalism is the most virtuous worldview. (shrink)

Bartha (2012) conjectures that, if we meet all of the other objections to Pascal’s wager, then the many-Gods objection is already met. Moreover, he shows that, if all other objections to Pascal’s wager are already met, then, in a choice between a Jealous God, an Indifferent God, a Very Nice God, a Very Perverse God, the full range of Nice Gods, the full range of Perverse Gods, and no God, you should wager on the Jealous God. I argue that his (...) requirement of [strongly] stable equilibrium is not well-motivated. There are other types of Gods, no less worthy of consideration than those that figure in Bartha’s deliberations, which are intuitively no worse wagers than the Jealous God. In particular, I have suggested that one does no worse to wager on a jealous cartel than one does to wager on a Jealous God. Moreover, I argue that there are other types of Gods, no less worthy of consideration than those that figure in Bartha’s deliberations, that make trouble for Pascal’s wager, but not because one would do better to wager on them rather than on a Jealous God. Finally, I argue that, if we suppose that infinitesimal credences are in no worse standing the infinite utilities, then we cannot accept the assumption—built into the relative utilities framework—that there cannot be infinitesimal credences. (shrink)

I argue that the Hume of the Treatise maintains an account of knowledge according to which (i) every instance of knowledge must be an immediately present perception (i.e., an impression or an idea); (ii) an object of this perception must be a token of a knowable relation; (iii) this token knowable relation must have parts of the instance of knowledge as relata (i.e., the same perception that has it as an object); and any perception that satisfies (i)-(iii) is an instance (...) of knowledge. I then apply this account to the case of sense perception. I argue that Hume holds that relations of impressions can be intuited, are knowable, and are necessary. For Hume, these relations constitute sensory knowledge. While Hume is rightly labeled an empiricist for many reasons, a close inspection of his account of knowledge reveals yet another way in which he deserves the label. (shrink)

In this paper, I will argue that Locke is a substance dualist in the general sense, in that he holds that there are, independent of our classificatory schema, two distinct kinds of substances: wholly material ones and wholly immaterial ones. On Locke’s view, the difference between the two lies in whether they are solid or not, thereby differentiating him from Descartes. My way of establishing Locke as a general substance dualist is to be as minimally committal as possible at the (...) outset, especially with respect to the classic debates on Locke’s positions in this domain, including those concerning substrata, real essences, and the like. Nonetheless, I show that minimal commitments about Locke’s primary/secondary quality distinction are sufficient to derive some substantive conclusions about his positions on these issues, as well as that he is a general substance dualist. (shrink)

E.J.Lowe was a prominent and theistically–inclined philosopher who developed and defended a four–category ontology with roots in Aristotle’s Categories. But Lowe engaged in little philosophical theology and said even less about how a divine being might fit into his considered ontology. This paper explores ways in which the reality of a divine being might be squared with Lowe’s ontology. I motivate the exploration with a puzzle that suggests Lowe must reject either divine aseity or the traditional view that God is (...) a substance. After showing that the puzzle cannot be overcome by rejecting one of its premises, I consider ways in which Lowe might try to reject the puzzle wholesale. I argue that the best way to reject the puzzle is to countenance a fifth fundamental category, the category of supernatural substance. (shrink)

This paper evaluates the claim that some desires provide reasons in virtue of their connection with conscious affective experiences like feelings of attraction or aversion. I clarify the nature of affective desires and several distinct ways in which affective desires might provide reasons. Against accounts proposed by Ruth Chang, Declan Smithies and Jeremy Weiss, I motivate doubts that it is the phenomenology of affective experiences that explains their normative or rational significance. I outline an alternative approach that centralises the function (...) of such experiences. (shrink)

This chapter is an invited contribution to a book on the naturalness of theistic belief. I start by considering ordinary usage of the term 'natural'. I then clarify how I shall use the terms 'naturalism', 'theism', 'worldview' and 'big picture'. I consider the demographic spread of commitment to theistic big pictures and naturalistic big pictures. I consider the distribution of happiness over those committed to theistic big pictures and naturalistic big pictures. I consider the distribution of reasons over those committed (...) to theistic big pictures and naturalistic big pictures. I consider whether intuitive considerations favour one kind of big picture over the other. As it often the case, I draw somewhat irenic conclusions from these considerations. (shrink)

This paper argues that considerations about causal origins of the universe do not favour theism over naturalism. Indeed, if the only data that is relevant to the choice between theism and naturalism is data about causal origins, then it turns out that considerations about causal origins favour naturalism over theism.

The transformative power of artificial intelligence (AI) is coming to philosophy—the only question is the degree to which philosophers will harness it. In this paper, we argue that the application of AI tools to philosophy could have an impact on the field comparable to the advent of writing, and that it is likely that philosophical progress will significantly increase as a consequence of AI. The role of philosophers in this story is not merely to use AI but also to help (...) develop it and theorize about it. In fact, we argue that philosophers have a prima facie obligation to spend significant effort in doing so, at least insofar as they should spend effort philosophizing. (shrink)

This paper is an English version of the paper that was published in German under the title: "Über die Aussichten erfolgreicher Beweise für Theismus oder Atheismus". My English paper was translated into German by Gabriele Schlegel. -/- The aim of this paper is to examine the prospects for proofs or successful arguments for the existence or non-existence of God.

Bu [makalede], nihai olarak kesin bir sonucu olduğunu iddia etmemekle birlikte, ateizm için geliştirebileceğim en iyi argümanı öne sürmeye çalışacağım ve ortaya koyacağım şeyin, Tanrı’nın varlığına dair yürütülen tartışmaların herhangi bir kısmındaki, en iyi argüman olduğunu iddia edeceğim.

Hsueh M. Qu has recently argued that Hume’s famed ‘Separability Principle’ from the Treatise entangles him in a contradiction. Qu offers a modified principle as a solution but also argues that the mature Hume would not have needed to avail himself of it, given that Hume’s arguments in the first Enquiry do not depend on this principle in any form. To the contrary, I show that arguments in the first Enquiry depend on this principle, but I agree with Qu that (...) Qu’s solution to Hume’s quandary frees him of the contradiction. Next, I compare Qu’s solution to Hume’s original position. By analysing the divergent forms of 'Hume’s Dictum’ that follow from them, I show that Qu’s solution and Hume’s original position have significantly different consequences in a range of domains, including Hume’s modality. Generally, Qu’s solution fits better with Hume’s other commitments—even though Hume often fails to recognize it—thereby increasing its plausibility. (shrink)

Some of Aristotle’s statements about the indemonstrability of the Principle of Non-Contradiction (PNC) in Metaphysics Γ 4 merit more attention. The consensus seems to be that Aristotle provides two arguments against the demonstrability of the PNC, with one located in Γ 3 and the other found in the first paragraph of Γ 4. In this article, I argue that Aristotle also relies upon a third argument for the same conclusion: the argument from truth. Although Aristotle does not explicitly state this (...) argument, it is the best argument that he could use to defend some of his statements in the second paragraph of Γ 4. Since the argument relies on only a few of Aristotle’s core views about truth, I propose that it is faithful to his considered position throughout his corpus, and it may be the strongest argument he could offer for the indemonstrability of the PNC. (shrink)

This paper rejects the imposition of "semantic innocence" as a constraint on semantic theories. In particular, it argues that recent attempts to justify the imposition of "semantic innocence" as a constraint on semantic theories fail.

In this paper, I review evidence which strongly supports the claim that life will eventually be extinguished from the universe. I then examine the ethical implications of this evidence, focusing, in particular, on the question whether it is a bad thing that life will eventually die out.

Hylomorphism is the Aristotelian theory according to which substances are composed of matter and form. If a house is a substance, then its matter would be a collection of bricks and timbers and its form something like the structure of those bricks and timbers. It is widely agreed that matter bears a mereological relationship to substance; the bricks and timbers are parts of the house. But with form things are more controversial. Is the structure of the bricks and timbers best (...) conceived as a part of the house, or is it related to the house in some non-mereological fashion? Kathrin Koslicki argues that substances have formal parts, that forms are best conceived as bearing a mereological relation to substances. This paper shows that her argument fails, given the traditional and plausible distinction between substances and accidental unities. I close with a brief suggestion for a non-mereological construal of forms. (shrink)

According to the Acceptance Principle, a person is entitled to accept a proposition that is presented as true (asserted) and that is intelligible to him or her, unless there are stronger reasons not to. Burge assumes this Principle and then argues that it has an apriori justification, basis or rationale. This paper expounds Burge's teleological reliability framework and the details of his a priori justification for the Principle. It then raises three significant doubts.

This paper is a discussion of an ontological argument defended by E. J. Lowe in the *Routledge Companion to Philosophy of Religion* (edited by C. Meister and P. Copan, at pp.332-40). The volume to which this paper belongs contains an article by Lowe which defends a different ontological argument from the one that I discuss.

General discussion of ontological arguments. (Extended the discussion of ontological arguments in the then current version of my SEP entry on ontological arguments.).

This chapter provides a quick sketch of the history of western philosophy of religion as it bears on theism.

Naturalists have many and diverse reasons for thinking that morality does not depend upon God. In this paper, I do not aim to give an exhaustive inventory of these reasons. Rather, I aim to give reason that emerge from the kind of naturalism that I accept. After explaining what I mean by "God", "morality" and "dependence", I note that, on the kind of naturalism that I accept, it is impossible that God exists. Unsurprisingly, therefore, I hold that it is impossible (...) that morality depends on God. While--as I go on to discuss--there are reasons to think that morality could not be dependent on anything else, I also canvass reasons for thinking that even theists should worry about the suggestion that morality might be dependent on God. -/- This chapter was published in a 'debate' book. My 'debate' partner was Matthew Flannagan. The book also contains my response to Flannagan's chapter on this topic. I have not included that response here. (shrink)

Argument mapping is a way of diagramming the logical structure of an argument to explicitly and concisely represent reasoning. The use of argument mapping in critical thinking instruction has increased dramatically in recent decades. This paper overviews the innovation and provides a procedural approach for new teaches wanting to use argument mapping in the classroom. A brief history of argument mapping is provided at the end of this paper.

It is uncontroversial that artifacts like statues and tables are mind-dependent. What is controversial is whether and how this mind-dependence has implications for the ontology of artifacts. I argue the mind-dependence of artifacts entails that there are no artifacts or artifact joints in the extra-mental world. In support of this claim, I argue that artifacts and artifact joints lack any extra-mental grounding, and so ought not to have a spot in a realist ontology. I conclude that the most plausible story (...) about artifacts is that they are in minds of suitably intelligent creatures, and not the extra-mental world. Artifacts and their joints are merely mental projections onto a world of ‘indifferent materials’. With this established, I show how many cases of object coincidence, the view that more than one material object can be located in the same exact region of space-time, cannot occur. (shrink)

Commonsense holds that testimony transfers knowledge from a speaker to the hearer. If the speaker has knowledge, then the hearer acquires it. Call that sufficiency. And a hearer acquires knowledge only if the speaker has it to transfer. Call that necessity. This article reviews counterexamples--and some replies to those counterexamples--to both claims.