This is the first modern study of Agrippa's occult philosophy as a coherent part of his intellectual work.

Presents a history of early Buddhism based solely on dateable artefacts and archaeology rather than received tradition, much of which data is provided by studying Pyrrho's history.

Human language is a salient example of a neurocognitive system that is specialized to process complex dependencies between sensory events distributed in time, yet how this system evolved and specialized remains unclear. Artificial Grammar Learning (AGL) studies have generated a wealth of insights into how human adults and infants process different types of sequencing dependencies of varying complexity. The AGL paradigm has also been adopted to examine the sequence processing abilities of nonhuman animals. We critically evaluate this growing literature in (...) species ranging from mammals (primates and rats) to birds (pigeons, songbirds, and parrots) considering also cross‐species comparisons. The findings are contrasted with seminal studies in human infants that motivated the work in nonhuman animals. This synopsis identifies advances in knowledge and where uncertainty remains regarding the various strategies that nonhuman animals can adopt for processing sequencing dependencies. The paucity of evidence in the few species studied to date and the need for follow‐up experiments indicate that we do not yet understand the limits of animal sequence processing capacities and thereby the evolutionary pattern. This vibrant, yet still budding, field of research carries substantial promise for advancing knowledge on animal abilities, cognitive substrates, and language evolution. (shrink)

Charles Goodman 's Response to the thoughtful paper by Adrian Kuzminski in this volume is actually devoted mainly to my book Greek Buddha. Half a century ago, Thomas Kuhn famously coined the term incommensurability to refer to the inability or unwillingness of many scholars in a given field to understand substantially new work. He describes their reactions against it and their attempts to suppress or discredit it. The reason for their response is that new discoveries advance science by challenging and (...) displacing old beliefs and practices. Kuhn accurately describes G's Response.When I wrote Greek Buddha, I assumed that the potential readership... (shrink)

In the developing and adult cortex, just as in the adult hippocampus, LTP is unable to account for a variety of types of functional plasticity.

Empirical advances have been made in understanding how human language, in its combinatorial complexity and unbounded expressivity, may have evolved from the communication systems present in our evolutionary ancestors. However, a number of cognitive processes and neurobiological mechanisms that support language may not have evolved specifically for communication, but rather from abilities that support perception and cognition more generally. We review recent evidence from comparative behavioural and neurobiological studies on structured sequence learning in human and nonhuman primates. These studies support (...) the notion that certain sequence learning abilities are evolutionarily conserved and engage corresponding inferior frontal brain regions across the species, regions also involved in processing language in humans. Alongside the cross-species similarities is evidence for human specialisations, illuminating the likely evolutionary pathways towards language in modern humans. We argue that cognitive abilities that were in place for animals to learn combinatorial relationships in the sensory world were available and co-opted for language in humans. (shrink)

This paper argues that the medical conception of health as absence of disease is a value-free theoretical notion. Its main elements are biological function and statistical normality, in contrast to various other ideas prominent in the literature on health. Apart from universal environmental injuries, diseases are internal states that depress a functional ability below species-typical levels. Health as freedom from disease is then statistical normality of function, i.e., the ability to perform all typical physiological functions with at least typical efficiency. (...) This conception of health is as value-free as statements of biological function. The view that health is essentially value-laden, held by most writers on the topic, seems to have one of two sources: an assumption that health judgments must be practical judgments about the treatment of patients, or a commitment to "positive" health beyond the absence of disease. I suggest that the assumption is mistaken, the commitment possibly misdescribed. (shrink)

This paper investigates the way that linguistic expressions influence vagueness, focusing on the interpretation of the positive (unmarked) form of gradable adjectives. I begin by developing a semantic analysis of the positive form of ‘relative’ gradable adjectives, expanding on previous proposals by further motivating a semantic basis for vagueness and by precisely identifying and characterizing the division of labor between the compositional and contextual aspects of its interpretation. I then introduce a challenge to the analysis from the class of ‘absolute’ (...) gradable adjectives: adjectives that are demonstrably gradable, but which have positive forms that relate objects to maximal or minimal degrees, and do not give rise to vagueness. I argue that the truth conditional difference between relative and absolute adjectives in the positive form stems from the interaction of lexical semantic properties of gradable adjectives—the structure of the scales they use—and a general constraint on interpretive economy that requires truth conditions to be computed on the basis of conventional meaning to the extent possible, allowing for context dependent truth conditions only as a last resort. (shrink)

Event-causal libertarians maintain that an agent’s freely bringing about a choice is reducible to states and events involving him bringing about the choice. Agent-causal libertarians demur, arguing that free will requires that the agent be irreducibly causally involved. Derk Pereboom and Meghan Griffith have defended agent-causal libertarianism on this score, arguing that since on event-causal libertarianism an agent’s contribution to his choice is exhausted by the causal role of states and events involving him, and since these states and events leave (...) it open which decision he will make, he does not settle which decision occurs, and thus “disappears.” My aim is to explain why this argument fails. In particular, I demonstrate that event-causal libertarians can dismantle the argument by enriching the reductive base in their analysis of free will to include a state that plays the functional role of the self-determining agent and with which the agent is identified. (shrink)

The debate over whether Frankfurt-style cases are counterexamples to the principle of alternative possibilities has taken an interesting turn in recent years. Frankfurt originally envisaged his attack as an attempting to show that PAP is false—that the ability to do otherwise is not necessary for moral responsibility. To many this attack has failed. But Frankfurtians have not conceded defeat. Neo-Frankfurtians, as I will call them, argue that the upshot of Frankfurt-style cases is not that PAP is false, but that it (...) is explanatorily irrelevant. Derk Pereboom and David Hunt’s buffer cases are tailor made to establish this conclusion. In this paper I come to the aid of PAP, showing that buffer cases provide no reason for doubting either its truth or relevance with respect to explaining an agent’s moral responsibility. (shrink)

Serious actualism is the view that it is metaphysically impossible for an entity to have a property, or stand in a relation, and not exist. Fine (1985) and Pollock (1985) influentially argue that this view is false. In short, there are properties like the property of nonexistence, and it is metaphysically possible that some entity both exemplifies such a property and does not exist. I argue that such arguments are indeed successful against the standard formulation of serious actualism. However, I (...) also argue that we should distinguish a weaker formulation of serious actualism using the actualist distinction between truth in, and truth at, a possible world. This weaker formulation is then shown to be consistent with the existence and possible exemplification of properties like the property of nonexistence. I end with a novel argument for the truth of the weaker formulation. (shrink)

In this paper I seek to defend libertarianism about free will and moral responsibility against two well-known arguments: the luck argument and the Mind argument. Both of these arguments purport to show that indeterminism is incompatible with the degree of control necessary for free will and moral responsibility. I begin the discussion by elaborating these arguments, clarifying important features of my preferred version of libertarianism—features that will be central to an adequate response to the arguments—and showing why a strategy of (...) reconciliation (often referred to as “deliberative libertarianism”) will not work. I then consider four formulations of the luck argument and find them all wanting. This discussion will place us in a favorable position to understand why the Mind argument also fails. (shrink)

In my view, gratitude is better understood as a virtue than as a source of duties. In addition to showing how virtue theory provides a better match for our moral phenomenology of gratitude, I argue that recent work in the area of the suberogatory, our considered judgments concerning the role of third parties, our reluctance to posit claim‐rights to gratitude, and the observations of preceding studies of the subject all lend support to my contention that the language of duties is (...) ill‐suited to describe the moral dynamics of gratitude. (shrink)

One of the most pressing objections against Divine simplicity is that it entails what is commonly termed a ‘modal collapse’, wherein all contingency is eliminated and every true proposition is rendered necessarily true. In this paper, I show that a common form of this argument is in fact famously invalid and examine three ways in which the opponent of Divine simplicity might try to repair the argument. I conclude that there is no clear way of repairing the argument that does (...) not beg the question against the doctrine of Divine simplicity. (shrink)

Positional goods are goods whose relative amount determines their absolute value. Many goods appear to have positional aspects. For example, one’s relative standing in the distribution of education and wealth may determine one’s absolute condition with respect to goods like employment opportunities, self-respect, and social inclusion. Positional goods feature in recent arguments from T.M. Scanlon, Brian Barry, and Harry Brighouse and Adam Swift that assert that we should favor egalitarian distributions of positional goods even if we reject equality as a (...) fundamental principle of distributive justice. With respect to positional goods, worsening the better off is required to better the worse off. Thus, we have reason to “level down” goods such as education and wealth in order to benefit those worse off with respect to the value of those goods. I argue that the allegedly positional aspects of the goods in question are not actually positional. Moreover, leveling down these goods risks self-defeat: it may produce a net decrease in the value of the shares of individuals with less of such goods. If so, leveling down measures would fail on their own terms. (shrink)

Let serious propositional contingentism (SPC) be the package of views which consists in (i) the thesis that propositions expressed by sentences featuring terms depend, for their existence, on the existence of the referents of those terms, (ii) serious actualism—the view that it is impossible for an object to exemplify a property and not exist—and (iii) contingentism—the view that it is at least possible that some thing might not have been something. SPC is popular and compelling. But what should we say (...) about possible worlds, if we accept SPC? Here, I first show that a natural view of possible worlds, well-represented in the literature, in conjunction with SPC is inadequate. Though I note various alternative ways of thinking about possible worlds in response to the first problem, I then outline a second more general problem—a master argument—which generally shows that any account of possible worlds meeting very minimal requirements will be inconsistent with compelling claims about _mere possibilia_ which the serious propositional contingentist should accept. (shrink)

Ectogestation involves the gestation of a fetus in an ex utero environment. The possibility of this technology raises a significant question for the abortion debate: Does a woman’s right to end her pregnancy entail that she has a right to the death of the fetus when ectogestation is possible? Some have argued that it does not Mathison & Davis. Others claim that, while a woman alone does not possess an individual right to the death of the fetus, the genetic parents (...) have a collective right to its death Räsänen. In this paper, I argue that the possibility of ectogestation will radically transform the problem of abortion. The argument that I defend purports to show that, even if it is not a person, there is no right to the death of a fetus that could be safely removed from a human womb and gestated in an artificial womb, because there are competent people who are willing to care for and raise the fetus as it grows into a person. Thus, given the possibility of ectogestation, the moral status of the fetus plays no substantial role in determining whether there is a right to its death. (shrink)

In the Sleeping Beauty problem, Beauty is uncertain whether the outcome of a certain coin toss was heads or tails. One argument suggests that her degree of belief in heads should be 1/3, while a second suggests that it should be 1/2. Prima facie, the argument for 1/2 appears to be stronger. I offer a diachronic Dutch Book argument in favor of 1/3. Even for those who are not routinely persuaded by diachronic Dutch Book arguments, this one has some important (...) morals. (shrink)

I distinguish several doctrines that economic methodologists have found attractive, all of which have a positivist flavour. One of these is the doctrine that preference assignments in economics are just shorthand descriptions of agents' choice behaviour. Although most of these doctrines are problematic, the latter doctrine about preference assignments is a respectable one, I argue. It doesn't entail any of the problematic doctrines, and indeed it is warranted independently of them.

Brauer (2022) has recently argued that if it is possible that there is nothing, then the correct modal logic for metaphysical modality cannot include D. Here, I argue that Brauer’s argument is unsuccessful; or at the very least significantly weaker than presented. First, I outline a simple argument for why it is not possible that there is nothing. I note that this argument has a well-known solution involving the distinction between truth in and truth at a possible world. However, I (...) then argue that once the semantics presupposed by Brauer’s argument is reformulated in terms of truth at a world, we have good reasons to think that a crucial semantic premise in Brauer’s argument should be rejected in favour of an alternative. Brauer’s argument is, however, no longer valid with this alternative premise. Thus, plausibly Brauer’s argument against D is only valid, if it is not sound. (shrink)

I argue that the theory of chance proposed by David Lewis has three problems: (i) it is time asymmetric in a manner incompatible with some of the chance theories of physics, (ii) it is incompatible with statistical mechanical chances, and (iii) the content of Lewis's Principal Principle depends on how admissibility is cashed out, but there is no agreement as to what admissible evidence should be. I proposes two modifications of Lewis's theory which resolve these difficulties. I conclude by tentatively (...) proposing a third modification of Lewis's theory, one which explains many of the common features shared by the chance theories of physics. (shrink)

The coherence objection to the doctrine of the Incarnation maintains that it is impossible for one individual to have both the attributes of God and the attributes of a human being. This article examines Thomas Aquinas’s answer to this objection. I challenge the dominant, mereological interpretation of Aquinas’s position and, in light of this challenge, develop and defend a new alternative interpretation of Aquinas’s response to this important objection to Christian doctrine.

In this paper, I argue that our practice of giving and demanding apologies is rationalized by a belief that apologies make a difference to our normative situation. The characteristic normative effects of an apology are, I claim, that it removes an obligation on others to distance themselves from the wrongdoer, and that it makes the apologizer personally accountable to the addressee for their future compliance with the obligation they violated. However, if we ask what rationalizes that belief, two influential views (...) on the literature on apology – that I call the Reassurance View and the Performing Deference View – prove to be inadequate. In particular, these views cannot explain how apology can be both an expression of remorse for one’s wrongdoing but also a performative through which, by carrying out certain canonical actions, one can – all at once – change one’s normative situation. In order to explain these features of apology, I suggest that we see apology as akin to a normative power, but a normative power that is exercised expressively, or by an expressive action. In particular, I suggest that we see the power of apology as exercised by the performance of the expressive action of dissociation. (shrink)

Nearly all defences of the agent-causal theory of free will portray the theory as a distinctively libertarian one — a theory that only libertarians have reason to accept. According to what I call ‘the standard argument for the agent-causal theory of free will’, the reason to embrace agent-causal libertarianism is that libertarians can solve the problem of enhanced control only if they furnish agents with the agent-causal power. In this way it is assumed that there is only reason to accept (...) the agent-causal theory if there is reason to accept libertarianism. I aim to refute this claim. I will argue that the reasons we have for endorsing the agent-causal theory of free will are nonpartisan. The real reason for going agent-causal has nothing to do with determinism or indeterminism, but rather with avoiding reductionism about agency and the self. As we will see, if there is reason for libertarians to accept the agent-causal theory, there is just as much reason for compatibilists to accept it. It is in this sense that I contend that if anyone should be an agent-causalist, then everyone should be an agent-causalist. (shrink)

Blaming (construed broadly to include both blaming-attitudes and blaming-actions) is a puzzling phenomenon. Even when we grant that someone is blameworthy, we can still sensibly wonder whether we ought to blame him. We sometimes choose to forgive and show mercy, even when it is not asked for. We are naturally led to wonder why we shouldn’t always do this. Wouldn’t it be a better to wholly reject the punitive practices of blame, especially in light of their often undesirable effects, and (...) embrace an ethic of unrelenting forgiveness and mercy? In this paper I seek to address these questions by offering an account of blame that provides a rationale for thinking that to wholly forswear blaming blameworthy agents would be deeply mistaken. This is because, as I will argue, blaming is a way of valuing, it is “a mode of valuation.” I will argue that among the minimal standards of respect generated by valuable objects, notably persons, is the requirement to redress disvalue with blame. It is not just that blame is something additional we are required to do in properly valuing, but rather blame is part of what that it is to properly value. Blaming, given the existence of blameworthy agents, is mode of valuation required by the standards of minimal respect. To forswear blame would be to fail value what we ought to value. (shrink)

I am going to argue for a robust realism about magnitudes, as irreducible elements in our ontology. This realistic attitude, I will argue, gives a better metaphysics than the alternatives. It suggests some new options in the philosophy of science. It also provides the materials for a better account of the mind’s relation to the world, in particular its perceptual relations.

I argue that the most common interpretation of experiential transparency’s significance is laden with substantive and ultimately extraneous metaphysical commitments. I divest this inflated interpretation of its unwarranted encumbrances and consolidate the precipitate into a position I call core transparency. Core Transparency is a thesis about experience’s presentational character. The objects of perceptual experience are there, present to us, in a way that the objects of most beliefs and judgments are not. According to core transparency, it is in the disclosure (...) of that which is central to experience’s presentational character, an intrinsic and irreducibly phenomenal aspect of experience I call phenomenal presence, that transparency’s significance principally consists. Phenomenal presence is uniquely positioned to illuminate the relationship between perceptual experience’s most important features: its intentionality and its phenomenality. The position I defend comprises two main claims. (1) The representational features of experience, understood in isolation from experiential phenomenality, neither constitute nor explain phenomenal presence. Consequently, the representational features of experience neither determine completely nor explain exhaustively experiential phenomenality. (2) Phenomenal presence is not representational, but is nevertheless the minimal realization of experiential intentionality. (shrink)

Propositional contingentism is the view that what propositions there are is a contingent matter—certain propositions ontologically depend on objects which themselves only contingently exist. Possible worlds are, loosely, complete ways the world could have been. That is to say, the ways in which everything in its totality could have been. Propositional contingentists make use of possible worlds frequently. However, a neglected, but important, question concerns whether there are any notions of worlds which are both theoretically adequate and consistent with propositional (...) contingentism. Some notion of a possible world is adequate if the systematic connection between, at least, possibility and truth at some possible world holds. Here, I argue that no adequate notion of a possible world is available to at least those who subscribe to one natural formulation of propositional contingentism. I also show that this result contrasts with a simple and adequate definition of a possible world available to the necessitist—those who hold that necessarily everything necessarily exists. (shrink)

I show that the existence of an omniscient, omnipotent, and essentially omnimalevolent being is impossible given only two metaethical assumptions (viz., moral rationalism and reasons internalism). I then argue (pace Stephen Law) that such an impossibility undercuts Law’s (Relig Stud 46(3):353–373, 2010) evil god challenge.

Drawing on Ezekiel Emanuel’s controversial piece ‘Why I hope to die at 75,’ I distinguish two types of concern in ethical debates about extending the human lifespan. The first focusses on the value of living longer from prudential and social perspectives. The second type of concern, which has received less attention, focusses on the value of aiming for longer life. This distinction, which is overlooked in the ethical literature on life extension, is significant because there are features of human psychology (...) and the structure of a life that should give pause when considering how long one should aim to live, but which do not neatly coincide with considerations about how valuable additional life is likely to be. I argue that, while Emanuel’s case for hoping to die at 75 is unconvincing, he nonetheless provides weak pro tanto considerations in favour of taking a moderate life span as a prudential aim around which to base at least some significant life plans. (shrink)

I will argue, pace a great many of my contemporaries, that there's something right about Boltzmann's attempt to ground the second law of thermodynamics in a suitably amended deterministic time-reversal invariant classical dynamics, and that in order to appreciate what's right about (what was at least at one time) Boltzmann's explanatory project, one has to fully apprehend the nature of microphysical causal structure, time-reversal invariance, and the relationship between Boltzmann entropy and the work of Rudolf Clausius.

In the quantum-Bayesian approach to quantum foundations, a quantum state is viewed as an expression of an agent’s personalist Bayesian degrees of belief, or probabilities, concerning the results of measurements. These probabilities obey the usual probability rules as required by Dutch-book coherence, but quantum mechanics imposes additional constraints upon them. In this paper, we explore the question of deriving the structure of quantum-state space from a set of assumptions in the spirit of quantum Bayesianism. The starting point is the representation (...) of quantum states induced by a symmetric informationally complete measurement or SIC. In this representation, the Born rule takes the form of a particularly simple modification of the law of total probability. We show how to derive key features of quantum-state space from (i) the requirement that the Born rule arises as a simple modification of the law of total probability and (ii) a limited number of additional assumptions of a strong Bayesian flavor. (shrink)

I argue, contrary to standard claims, that accomplice liability need not be a causal relation. One can be an accomplice to another’s crime without causally contributing to the criminal act of the principal. This is because the acts of aid and encouragement that constitute the basis for accomplice liability typically occur in contexts of under- and over-determination, where causal analysis is confounded. While causation is relevant to justifying accomplice liability in general, only potential causation is necessary in particular cases. I (...) develop this argument through the example of the role of U.S. legal officials in abetting the acts of unlawful interrogation that have taken place since 2001. I also suggest that there may be a limited justification for ex post ratificatory accomplice liability. (shrink)

A standard view of trust sees trust as intimately related to reliance; on this standard view, trust is reliance plus some other factor. A significant literature has now developed that seeks to explain what factor, in addition to reliance, serves to distinguish cases of trust from cases of mere reliance. I argue that this approach to the analysis of trust is misguided. Although reliance, properly understood, frequently accompanies trust, reliance is not a necessary condition of trust.

Applied ethics is home to numerous productive subfields such as procreative ethics, intergenerational ethics and environmental ethics. By contrast, there is far less ethical work on ageing, and there is no boundary work that attempts to set the scope for ‘ageing ethics’ or the ‘ethics of ageing’. Yet ageing is a fundamental aspect of life; arguably even more fundamental and ubiquitous than procreation. To remedy this situation, I examine conceptions of what the ethics of ageing might mean and argue that (...) these conceptions fail to capture the requirements of the desired subfield. The key reasons for this are, first, that they view ageing as something that happens only when one is old, thereby ignoring the fact that ageing is a process to which we are all subject, and second that the ageing person is treated as an object in ethical discourse rather than as its subject. In response to these shortcomings I put forward a better conception, one which places the ageing person at the centre of ethical analysis, has relevance not just for the elderly and provides a rich yet workable scope. While clarifying and justifying the conceptual boundaries of the subfield, the proposed scope pleasingly broadens the ethics of ageing beyond common negative associations with ageing. (shrink)

The brand of cosmopolitanism that Cécile Fabre develops in her excellent book, Cosmopolitan Peace, leaves room for qualifying groups to exercise political self‐determination. Important questions thus emerge regarding who is entitled to have a say in the group's self‐determination, questions that take on a heightened practical urgency in the wake of wars that cause massive migration. In this article, I call into question Fabre's contention that the descendants of unjust occupants necessarily acquire occupancy rights which entitle them to a say (...) in the political self‐determination over the territory on which they currently reside. (shrink)

This paper argues for the legalization of vote markets. I contend that the state should not prohibit the sale of votes under certain institutional conditions. Jason Brennan has recently argued for the moral permissibility of vote selling; yet, thus far, no philosopher has argued for the legal permissibility of vote selling. I begin by giving four prima facie reasons in favour of legalizing vote markets. First, vote markets benefit both buyers and sellers. Second, citizens already enjoy significant discretion in their (...) use of their vote, including the ability to use their vote in ways antithetical to justice and the public interest. Third, vote markets are relevantly similar to other democratic practices that are legally permissible. Fourth, vote markets enable elections to better reflect the intensity of citizens’ preferences. Next, I reply to two counter-arguments. The first contends that vote markets will increase the political power of the wealthy; the second contends that votes must be used in the serv.. (shrink)

Philosophers have met with many problems in discussing the interconnected concepts being, identity, and truth, and have advanced many theories to deal with them. Williams argues that most of these problems and theories result from an inadequate appreciation of the ways in which the words "be," "same," and "true" work. By means of linguistic analysis he shows that being and truth are not properties, and identity is not a relation. He is thus able to demystify a number of metaphysical issues (...) concerning the meaning of the word "I," the relation between the mental and the physical, objects of thought, times and places, and the nature of reality. Williams presents his views clearly, with a minimum of technicality, and with rich and apt examples, so that they will be accessible to readers not versed in symbolic logic. (shrink)

Artificial intelligence (AI) assurance is an umbrella term describing many approaches—such as impact assessment, audit, and certification procedures—used to provide evidence that an AI system is legal, ethical, and technically robust. AI assurance approaches largely focus on two overlapping categories of harms: deployment harms that emerge at, or after, the point of use, and individual harms that directly impact a person as an individual. Current approaches generally overlook upstream collective and societal harms associated with the development of systems, such as (...) resource extraction and processing, exploitative labour practices and energy intensive model training. Thus, the scope of current AI assurance practice is insufficient for ensuring that AI is ethical in a holistic sense, i.e. in ways that are legally permissible, socially acceptable, economically viable and environmentally sustainable. This article addresses this shortcoming by arguing for a broader approach to AI assurance that is sensitive to the full scope of AI development and deployment harms. To do so, the article maps harms related to AI and highlights three examples of harmful practices that occur upstream in the AI supply chain and impact the environment, labour, and data exploitation. It then reviews assurance mechanisms used in adjacent industries to mitigate similar harms, evaluating their strengths, weaknesses, and how effectively they are being applied to AI. Finally, it provides recommendations as to how a broader approach to AI assurance can be implemented to mitigate harms more effectively across the whole AI supply chain. (shrink)

I distinguish three different concepts of causation: The scientific concept, or causal structure, is the subject of recent work in causal modeling. The folk attributive concept has been studied by philosophers of law and social psychologists. The metaphysical concept is the one that metaphysicians have attempted to analyze. I explore the relationships between these three concepts, and suggest that the metaphysical concept is an untenable and dispensable mixture of the other two.

Artificial grammar learning (AGL) is used to study how human adults, infants, animals or machines learn various sorts of rules defined over sounds or visual items. Ten Cate et al. introduce the topic and provide a critical synthesis of this important interdisciplinary area of research. They identify the questions that remain open and the challenges that lie ahead, and argue that the limits of human, animal and machine learning abilities have yet to be found.