The free-energy principle states that all systems that minimize their free energy resist a tendency to physical disintegration. Originally proposed to account for perception, learning, and action, the free-energy principle has been applied to the evolution, development, morphology, anatomy and function of the brain, and has been called a postulate, an unfalsifiable principle, a natural law, and an imperative. While it might afford a theoretical foundation for understanding the relationship between environment, life, and mind, its epistemic status is unclear. Also (...) unclear is how the free-energy principle relates to prominent theoretical approaches to life science phenomena, such as organicism and mechanism. This paper clarifies both issues, and identifies limits and prospects for the free-energy principle as a first principle in the life sciences. (shrink)

Courtesy of its free energy formulation, the hierarchical predictive processing theory of the brain (PTB) is often claimed to be a grand unifying theory. To test this claim, we examine a central case: activity of mesocorticolimbic dopaminergic (DA) systems. After reviewing the three most prominent hypotheses of DA activity—the anhedonia, incentive salience, and reward prediction error hypotheses—we conclude that the evidence currently vindicates explanatory pluralism. This vindication implies that the grand unifying claims of advocates of PTB are unwarranted. More generally, (...) we suggest that the form of scientific progress in the cognitive sciences is unlikely to be a single overarching grand unifying theory. (shrink)

The ontic conception of scientific explanation has been constructed and motivated on the basis of a putative lexical ambiguity in the term explanation. I raise a puzzle for this ambiguity claim, and then give a deflationary solution under which all ontically-rendered talk of explanation is merely elliptical; what it is elliptical for is a view of scientific explanation that altogether avoids the ontic conception. This result has revisionary consequences for New Mechanists and other philosophers of science, many of whom have (...) assimilated their conception of explanation to the ontic conception. (shrink)

As much as assumptions about mechanisms and mechanistic explanation have deeply affected psychology, they have received disproportionately little analysis in philosophy. After a historical survey of the influences of mechanistic approaches to explanation of psychological phenomena, we specify the nature of mechanisms and mechanistic explanation. Contrary to some treatments of mechanistic explanation, we maintain that explanation is an epistemic activity that involves representing and reasoning about mechanisms. We discuss the manner in which mechanistic approaches serve to bridge levels rather than (...) reduce them, as well as the different ways in which mechanisms are discovered. Finally, we offer a more detailed example of an important psychological phenomenon for which mechanistic explanation has provided the main source of scientific understanding. (shrink)

The aim of this paper is to provide an overview of various forms of alethic pluralism. Along the way we will draw a number of distinctions that, hopefully, will be useful in mapping the pluralist landscape. Finally, we will argue that a commitment to alethic disjunctivism, a certain brand of pluralism, might be difficult to avoid for adherents of the other pluralist views to be discussed. We will proceed as follows: Section 1 introduces alethic monism and alethic pluralism. Section 2 (...) presents a distinction between strong and moderate versions of monism and pluralism, understood as theses about the existence of truth properties. Section 3 introduces four pluralist positions: strong alethic pluralism, alethic disjunctivism, second-order functionalism and manifestation functionalism. These positions are classified using the basic framework from Section 2, and a further distinction between pure and mixed versions of pluralism is drawn. Interestingly, alethic disjunctivism and the two kinds of functionalism—i.e. three out of four positions— have a mixed character. They incorporate a monist thesis. The only pure form of pluralism is strong alethic pluralism. Section 4 adds another distinction to the stock: one-level and two-level views. Each of the mixed positions operates with two levels, locating certain “alethically potent”—or grounding—properties at a lower level and others at a higher level. We briefly discuss the nature of grounding. In Section 5, we answer a question about mixed, two-level views, viz. whether they are as much monist as pluralist in nature, or more. They are not. Section 6 is devoted to the task of arguing that the strong pluralist, the second-order functionalist, and the manifestation functionalist will find it hard to deny a commitment to alethic disjunctivism. (shrink)

Despite their success in describing and predicting cognitive behavior, the plausibility of so-called ‘rational explanations’ is often contested on the grounds of computational intractability. Several cognitive scientists have argued that such intractability is an orthogonal pseudoproblem, however, since rational explanations account for the ‘why’ of cognition but are agnostic about the ‘how’. Their central premise is that humans do not actually perform the rational calculations posited by their models, but only act as if they do. Whether or not the problem (...) of intractability is solved by recourse to ‘as if’ explanations critically depends, inter alia, on the semantics of the ‘as if’ connective. We examine the five most sensible explications in the literature, and conclude that none of them circumvents the problem. As a result, rational ‘as if’ explanations must obey the minimal computational constraint of tractability. (shrink)

The relative merits and demerits of historically prominent views such as the correspondence theory, coherentism, pragmatism, verificationism, and instrumentalism have been subject to much attention in the truth literature and have fueled the long-lived debate over which of these views is the most plausible one. While diverging in their specific philosophical commitments, adherents of these historically prominent views agree in at least one fundamental respect. They are all alethic monists. They all endorse the thesis that there is only one property (...) in virtue of which propositions can be true, and so, in this sense, take truth to be one. The truth pluralist, on the other hand, rejects this idea. There are several properties in virtue of which propositions can be true. The literature on truth pluralism has been growing steadily for the past twenty years. This volume, however, is the first of its kind—the first collection of papers focused specifically on pluralism about truth. Part I is dedicated to the development, investigation, and critical discussion of different forms of pluralism. An additional reason to look at truth pluralism with interest is the significant connections it bears to other debates in the truth literature—the debates concerning traditional theories of truth and the deflationism/inflationism divide being cases in hand. Parts II and III of the volume connect truth pluralism to these two debates. (shrink)

Due to the wide array of phenomena that are of interest to them, psychologists offer highly diverse and heterogeneous types of explanations. Initially, this suggests that the question "What is psychological explanation?" has no single answer. To provide appreciation of this diversity, we begin by noting some of the more common types of explanations that psychologists provide, with particular focus on classical examples of explanations advanced in three different areas of psychology: psychophysics, physiological psychology, and information-processing psychology. To analyze what (...) is involved in these types of explanations, we consider the ways in which law-like representations of regularities and representations of mechanisms factor in psychological explanations. This consideration directs us to certain fundamental questions, e.g., "To what extent are laws necessary for psychological explanations?" and "What do psychologists have in mind when they appeal to mechanisms in explanation?" In answering such questions, it appears that laws do play important roles in psychological explanations, although most explanations in psychology appeal to accounts of mechanisms. Consequently, we provide a unifying account of what psychological explanation is. (shrink)

Wesley Salmon’s version of the ontic conception of explanation is a main historical root of contemporary work on mechanistic explanation. This paper examines and critiques the philosophical merits of Salmon’s version, and argues that his conception’s most fundamental construct is either fundamentally obscure, or else reduces to a non-ontic conception of explanation. Either way, the ontic conception is a misconception.

Many cognitive scientists, having discovered that some computational-level characterization f of a cognitive capacity φ is intractable, invoke heuristics as algorithmic-level explanations of how cognizers compute f. We argue that such explanations are actually dysfunctional, and rebut five possible objections. We then propose computational-level theory revision as a principled and workable alternative.

What features will something have if it counts as an explanation? And will something count as an explanation if it has those features? In the second half of the 20th century, philosophers of science set for themselves the task of answering such questions, just as a priori conceptual analysis was generally falling out of favor. And as it did, most philosophers of science just moved on to more manageable questions about the varieties of explanation and discipline-specific scientific explanation. Often, such (...) shifts are sound strategies for problem-solving. But leaving fallow certain basic conceptual issues can also result in foundational debates. (shrink)

Traditional inflationary approaches that specify the nature of truth are attractive in certain ways; yet, while many of these theories successfully explain why propositions in certain domains of discourse are true, they fail to adequately specify the nature of truth because they run up against counterexamples when attempting to generalize across all domains. One popular consequence is skepticism about the efficaciousness of inflationary approaches altogether. Yet, by recognizing that the failure to explain the truth of disparate propositions often stems from (...) inflationary approaches' allegiance to alethic monism, pluralist approaches are able to avoid this explanatory inadequacy and the resulting skepticism, though at the cost of inviting other conceptual difficulties. A novel approach, alethic functionalism, attempts to circumvent the problems faced by pluralist approaches while preserving their main insights. Unfortunately, it too generates additional problems---namely, with its suspect appropriation of the multiple realizability paradigm and its platitude-based strategy---that need to be dissolved before it can constitute an adequate inflationary approach to the nature of truth. (shrink)

What is truth? Philosophers are interested in a range of issues involving the concept of truth beginning with what sorts of things can be true. This is a collection of eighteen new and original research papers on truth and other alethic phenomena by twenty of the most promising young scholars working on truth today.

Functionalists about truth employ Ramsification to produce an implicit definition of the theoretical term _true_, but doing so requires determining that the theory introducing that term is itself true. A variety of putative dissolutions to this problem of epistemic circularity are shown to be unsatisfactory. One solution is offered on functionalists' behalf, though it has the upshot that they must tread on their anti-pluralist commitments.

Although it’s sometimes thought that pluralism about truth is unstable—or, worse, just a non-starter—it’s surprisingly difficult to locate collapsing arguments that conclusively demonstrate either its instability or its inability to get started. This paper exemplifies the point by examining three recent arguments to that effect. However, it ends with a cautionary tale; for pluralism may not be any better off than other traditional theories that face various technical objections, and may be worse off in facing them all.

This chapter provides a brief overview of the history of behavioral neurology, dividing it roughly into six eras. In the ancient and classical eras, emphasis is placed on two transitions: firstly, from descriptions of head trauma and attempted neurosurgical treatments to the exploratory dissections during the Hellenistic period and the replacement of cardiocentrism; and secondly, to the more systematic investigations of Galenus and the rise of pneumatic ventricular theory. In the medieval through post-Renaissance eras, the scholastic consolidation of knowledge and (...) the role of compendia are emphasized, along with the use of new methods from within a mechanistic framework. With the discovery of electrical conductance and the rise of experimentalism, we frame the modern era as period of intense debate over localization, decomposition, and other mechanistic principles, and marked by rapid discovery about the brain. The chapter ends with a discussion of the contemporary era, focusing on the establishment of behavioral neurology research on aphasia, apraxia, and neuropsychiatric conditions. (shrink)

There is widespread recognition at universities that a proper understanding of science is needed for all undergraduates. Good jobs are increasingly found in fields related to Science, Technology, Engineering, and Medicine, and science now enters almost all aspects of our daily lives. For these reasons, scientific literacy and an understanding of scientific methodology are a foundational part of any undergraduate education. Recipes for Science provides an accessible introduction to the main concepts and methods of scientific reasoning. With the help of (...) an array of contemporary and historical examples, definitions, visual aids, and exercises for active learning, the textbook helps to increase students’ scientific literacy. The first part of the book covers the definitive features of science: naturalism, experimentation, modeling, and the merits and shortcomings of both activities. The second part covers the main forms of inference in science: deductive, inductive, abductive, probabilistic, statistical, and causal. The book concludes with a discussion of explanation, theorizing and theory-change, and the relationship between science and society. The textbook is designed to be adaptable to a wide variety of different kinds of courses. In any of these different uses, the book helps students better navigate our scientific, 21st-century world, and it lays the foundation for more advanced undergraduate coursework in a wide variety of liberal arts and science courses. Selling Points Helps students develop scientific literacy—an essential aspect of _any_ undergraduate education in the 21 st century, including a broad understanding of scientific reasoning, methods, and concepts Written for all beginning college students: preparing science majors for more focused work in particular science; introducing the humanities’ investigations of science; and helping non-science majors become more sophisticated consumers of scientific information Provides an abundance of both contemporary and historical examples Covers reasoning strategies and norms applicable in all fields of physical, life, and social sciences, _as well as_ strategies and norms distinctive of specific sciences Includes visual aids to clarify and illustrate ideas Provides text boxes with related topics and helpful definitions of key terms, and includes a final Glossary with all key terms Includes Exercises for Active Learning at the end of each chapter, which will ensure full student engagement and mastery of the information include earlier in the chapter Provides annotated ‘For Further Reading’ sections at the end of each chapter, guiding students to the best primary and secondary sources available Offers a Companion Website, with: For Students: direct links to many of the primary sources discussed in the text, student self-check assessments, a bank of exam questions, and ideas for extended out-of-class projects For Instructors: a password-protected Teacher’s Manual, which provides student exam questions with answers, extensive lecture notes, classroom-ready Power Point presentations, and sample syllabi Extensive Curricular Development materials, helping any instructor who needs to create a Scientific Reasoning Course, ex nihilo. (shrink)

When talking about truth, we ordinarily take ourselves to be talking about one-and-the-same thing. Alethic monists suggest that theorizing about truth ought to begin with this default or pre-reflective stance, and, subsequently, parlay it into a set of theoretical principles that are aptly summarized by the thesis that truth is one. Foremost among them is the invariance principle.

Psychoneural reductionists sometimes claim that sufficient amounts of lower-level explanatory achievement preclude further contributions from higher-level psychological research. Ostensibly, with nothing left to do, the effect of such preclusion on psychological explanation is extinction. Reductionist arguments for preclusion have recently involved a reorientation within the philosophical foundations of neuroscience---namely, away from the philosophical foundations and toward the neuroscience. In this chapter, I review a successful reductive explanation of an aspect of reward function in terms of dopaminergic operations of the mesocorticolimbic (...) system in order to demonstrate why preclusion/extinction claims are dubious. (shrink)

Attention to the conversational role of alethic terms seems to dominate, and even sometimes exhaust, many contemporary analyses of the nature of truth. Yet, because truth plays a role in judgment and assertion regardless of whether alethic terms are expressly used, such analyses cannot be comprehensive or fully adequate. A more general analysis of the nature of truth is therefore required – one which continues to explain the significance of truth independently of the role alethic terms play in discourse. We (...) undertake such an analysis in this paper; in particular, we start with certain elements from Kant and Frege, and develop a construct of truth as a normative modality of cognitive acts (e.g., thought, judgment, assertion). Using the various biconditional T-schemas to sanction the general passage from assertions to (equivalent) assertions of truth, we then suggest that an illocutionary analysis of truth can contribute to its locutionary analysis as well, including the analysis of diverse constructions involving alethic terms that have been largely overlooked in the philosophical literature. Finally, we briefly indicate the importance of distinguishing between alethic and epistemic modalities. (shrink)

"New wave" reductionism aims at advancing a kind of reduction that is stronger than unilateral dependency of the mental on the physical. It revolves around the idea that reduction between theoretical levels is a matter of degree, and can be laid out on a continuum between a "smooth" pole (theoretical identity) and a "bumpy" pole (extremely revisionary). It also entails that both higher and lower levels of the reductive relationship sustain some degree of explanatory autonomy. The new wave predicts that (...) reductions of folk psychology to neuroscience will be located in the middle of this continuum; as neuroscientific evidence about mental states checks in, theoretical folk psychology will therefore be moderately revised. However, the model has conceptual problems which preclude its success in reviving reductionism, and its commitment to a syntactic approach wrecks its attempt to rescue folk psychology. Moreover, the architecture of the continuum operates on a category mistake that sneaks in an eliminativist conclusion. I argue that new wave reductionism therefore tends to be eliminativism in disguise. (shrink)

Minimalists about truth contend that traditional inflationary theories systematically fail to explain certain facts about truth, and that this failure licenses a ‘reversal of explanatory direction’. Once reversed, they purport that their own minimal theory adequately explains all of the facts involving truth. But minimalists’ main objection to inflationism seems to misfire, and the subsequent reversal of explanatory direction, if it can be made sense of, leaves minimalism in no better explanatory position; and even if the objection were serviceable and (...) the reversal legitimate, minimalists’ adequacy thesis is still implausible. (shrink)

Advancement in cognitive science depends, in part, on doing some occasional ‘theoretical housekeeping’. We highlight some conceptual confusions lurking in an important attempt at explaining the human capacity for rational or coherent thought: Thagard & Verbeurgt’s computational-level model of humans’ capacity for making reasonable and truth-conducive abductive inferences (1998; Thagard, 2000). Thagard & Verbeurgt’s model assumes that humans make such inferences by computing a coherence function (f_coh), which takes as input representation networks and their pair-wise constraints and gives as output (...) a partition into accepted (A) and rejected (R) elements that maximizes the weight of satisfied constraints. We argue that their proposal gives rise to at least three difficult problems. (shrink)

Pluralists maintain that there is more than one truth property in virtue of which bearers are true. Unfortunately, it is not yet clear how they diagnose the liar paradox or what resources they have available to treat it. This chapter considers one recent attempt by Cotnoir (2013b) to treat the Liar. It argues that pluralists should reject the version of pluralism that Cotnoir assumes, discourse pluralism, in favor of a more naturalized approach to truth predication in real languages, which should (...) be a desideratum on any successful pluralist conception. Appealing to determination pluralism instead, which focuses on truth properties, it then proposes an alternative treatment to the Liar that shows liar sentences to be undecidable. (shrink)

Reductionism is an old doctrine desperate for new direction. With nomologically constructed theories commanding less attention in the life sciences, concern for the twentieth-century tradition of a...

This paper employs a case study from the history of neuroscience—brain reward function—to scrutinize the inductive argument for the so-called ‘Heuristic Identity Theory’ (HIT). The case fails to support HIT, illustrating why other case studies previously thought to provide empirical support for HIT also fold under scrutiny. After distinguishing two different ways of understanding the types of identity claims presupposed by HIT and considering other conceptual problems, we conclude that HIT is not an alternative to the traditional identity theory so (...) much as a relabeling of previously discussed strategies for mechanistic discovery. (shrink)

This paper adds to the philosophical literature on mechanistic explanation by elaborating two related explanatory functions of idealisation in mechanistic models. The first function involves explaining the presence of structural/organizational features of mechanisms by reference to their role as difference-makers for performance requirements. The second involves tracking counterfactual dependency relations between features of mechanisms and features of mechanistic explanandum phenomena. To make these functions salient, we relate our discussion to an exemplar from systems biological research on the mechanism for countering (...) heat shock—the heat shock response system—in Escherichia coli bacteria. This research also reinforces a more general lesson: ontic constraint accounts in the literature on mechanistic explanation provide insufficiently informative normative appraisals of mechanistic models. We close by outlining an alternative view on the explanatory norms governing mechanistic representation. (shrink)

The theme of this special issue is minimalism about truth, a conception which has attracted extensive support since the landmark publication of Paul Horwich's Truth (1990). Many well-esteemed philosophers have challenged Horwich's alethic minimalism, an especially austere version of deflationary truth theory. In part, this is at least because his brand of minimalism about truth also intersects with several different literatures: paradox, implicit definition, bivalence, normativity, propositional attitudes, properties, explanatory power, meaning and use, and so forth. Deflationist sympathizers have introduced (...) a few developments and emendations, while critics and other interlocutors have generated objections that have required further responses. Some of these works appeared in the first few years following the publication of the first edition of Truth. But others have appeared only in the last five or ten years, indicating that interest in the minimalist conception continues to bloom and be a highly fecund source for new ideas. Some of those new ideas are collected here, in a special issue celebrating collectively the 25th anniversary of Horwich's Truth in 2015 and the 20th anniversary of the revised edition in 2018. The intent of the issue is overwhelmingly prospective rather than retrospective; however, it presents original work and fresh perspectives, including a new contribution by Paul Horwich himself, that jointly offer au currant reflections on the current status and future promise of the minimal conception. (shrink)

Embodied Cognition is the kind of view that is all trees, no forest. Mounting experimental evidence gives it momentum in fleshing out the theoretical problems inherent in Cognitivists’ separation of mind and body. But the more its proponents compile such evidence, the more the fundamental concepts of Embodied Cognition remain in the dark. This conundrum is nicely exemplified by Pecher and Zwaan’s book, Grounding Cognition, which is a programmatic attempt to rally together an array of empirical results and linguistic data, (...) and its successes in this endeavor nicely epitomize current directions among the various research provinces of Embodied Cognition. The untoward drawback, however, is that such successes are symptomatic of the growing imbalance between experimental progress and theoretical interrogation. In particular, one of the theoretical cornerstones of Embodied Cognition —namely, the very concept of grounding under investigation here—continues to go unilluminated. Hence, the advent of this volume indicates that—now more than ever—the concept of grounding is in dire need of some plain old-fashioned conceptual analysis. In that sense, Embodied Cognition is grounded until further notice. (shrink)

Chrysostomos Mantzavinos (2016), Explanatory Pluralism. Cambridge University Press, xiv + 223 pp. £64.99 cloth.

The neuropsychopharmacological methods and theories used to investigate the nature of depression have been viewed as suspect for a variety of philosophical and scientific reasons. Much of this criticism aims to demonstrate that biochemical- and neurological-based theories of this mental illness are defective, due in part because the methods used in their service are consistently invalidated, failing to induce depression in pre-clinical animal models. Neuropsychopharmacologists have been able to stave off such criticism by showing that their methods are context and (...) domain-sensitive, and that the worth of an animal model is relative to its purpose – thereby creating logical space for the question of whether there could ever be a “good” animal model of depression. I contend that this sort of response implicitly leans on Feyerabendian principles in the philosophy of science, and exemplify this connection using a standard taxonomy of behavioral models of depression. I then take one central Feyerabendian principle – methodological and theoretical pluralism – and show how it maps onto the neuropsychopharmacological research tradition as it is currently practiced. (shrink)

Hypocretin regulates brain reward function and cocaine consumption in rats. The hypocretinergic (Hcrt) system is implicated in energy homeostasis, feeding and sleep regulation. Hypocretinergic cell bodies are located in the lateral hypothalamus (LH) and project throughout the brain. The aim of the present studies was to investigate the role of the Hcrt system in regulating brain reward function and the reinforcing properties of cocaine in rats. Intracranial self-stimulation (ICSS) thresholds provide an accurate measure of brain reward function in rats. Here (...) we show that a single injection of Hcrt-1 (5 µg icv) induced persistent, long-lasting elevations in ICSS thresholds in drug-naïve rats. Indeed, Hrct-1 elevated ICSS thresholds for 36 h, with peak elevations between 6 and 12 hours after injection. Hrct-1-induced threshold elevations were attenuated by an antibody known to neutralize the binding of hcrt-1 to its receptors. Taken together, these observations suggest that Hrct-1 negatively regulates brain reward function in rats. Because Hrct-1 negatively regulates brain reward function, we hypothesized that it may attenuate the increased brain reward function usually observed after cocaine consumption, and thereby alter cocaine self-administration behavior. A daily injection of Hrct-1 (1 µg icv), for 4 consecutive days, slightly increased cocaine self-administration (0.25 mg/infusion) in rats. Overall, these data demonstrate that Hrct-1 negatively regulates brain reward function, and as such may indirectly alter cocaine self-administration. Given the well-established role of hypocretin neurons in regulating feeding behavior and sleep, we hypothesize that hypocretinergic regulation of brain reward function may provide a mechanism by which appropriate and competing behaviors (e.g. sleep or feeding) may be engaged to maintain energy homeostasis. (shrink)

Elevations in brain stimulation reward (BSR) thresholds have been observed in rats undergoing nicotine withdrawal and have been proposed as a sensitive measure of the negative affective state associated with nicotine withdrawal. mGluR are presynaptic autoreceptors that decrease glutamate release when stimulated. The aim of this study was to examine the role of glutamate neurotransmission in nicotine dependence. The mGluR agonist LY314582 (2.5–7.5 mg/kg) precipitated nicotine withdrawal as measured by elevations in BSR thresholds in nicotine-treated rats but not in controls. (...) It was hypothesized that LY314582 precipitated nicotine withdrawal by decreasing glutamatergic tone at postsynaptic glutamate receptors. Therefore, the effects of MPEP (0.5–2 mg/kg), an mGluR antagonist, and MK-801 (0.01–1 mg/kg), an NMDA receptor antagonist, were examined. MPEP elevated BSR thresholds by an equal magnitude in control and nicotine-treated rats. At low doses, MK-801 (0.01–0.2 mg/kg) lowered BSR thresholds to a similar extent in control and nicotine-treated rats. At higher doses, MK-801 (0.25–1 mg/kg) disrupted performance in nicotine-treated and control rats. These data indicate that mGluR and NMDA receptors regulate BSR in opposite directions in non-dependent animals, and chronic nicotine treatment does not alter these effects. Most importantly, the data demonstrate that the mGluR is involved in nicotine dependence, but mGluR and NMDA receptors do not mediate mGluR actions in nicotine dependence. (shrink)

Essay on Cuyckens, Dirven, & Taylor (eds.) Cognitive Approaches to Lexical Semantics, with emphasis on work on polysemy, prototypicality, and contextual modulation.

We argue that the concepts of mechanism and autonomy appear to be antagonistic when autonomy is conflated with agency. Once these concepts are disentangled, it becomes clearer how autonomy emerges from complex forms of control. Subsequently, current biomimetic strategies tend to focus on homeostatic regulatory systems; we propose that research in AI and robotics would do well to incorporate biomimetic strategies that instead invoke models of allostatic mechanisms as a way of understanding how to enhance autonomy in artificial systems.