Recently, Weisbecker and Goswami presented the first comprehensive comparative analysis of brain size, metabolic rate, and development periods in marsupial mammals. In this paper, a strictly energetic perspective is applied to identify general mammalian correlates of brain size evolution. In both marsupials and placentals, the duration or intensity of maternal investment is a key correlate of relative brain size, but here I show that allomaternal energy subsidies may also play a role. In marsupials, an energetic constraint on brain (...) size in adults is only revealed if we consider both metabolic and reproductive rates simultaneously, because a strong trade‐off between encephalization and offspring production masks the positive correlation between basal metabolic rate and brain size in a bivariate comparison. In conclusion, starting from an energetic perspective is warranted to elucidate relations between ecology, social systems, life history, and brain size in all mammals. (shrink)

The human brain does not use more energy than the smaller brains of animals of comparable corporal weight. Uniquely, human functions localized largely in parts of the human brain that show greatest size increase over other animals may be mediated primarily by nonsynaptic neurotransmission, with reduced energy cost per kilogram of brain. This may affect the energetic constraints on evolution.

Unless one embraces activities as foundational, understanding activities in mechanisms requires an account of the means by which entities in biological mechanisms engage in their activities—an account that does not merely explain activities in terms of more basic entities and activities. Recent biological research on molecular motors exemplifies such an account, one that explains activities in terms of free energy and constraints. After describing the characteristic “stepping” activities of these molecules and mapping the stages of those steps onto the (...) stages of the motors’ hydrolytic cycles, researchers pieced together from images of the molecules in different hydrolyzation states accounts of how the chemical energy in ATP is transformed in the constrained environments of the motors into the characteristic activities of the motors. We argue that New Mechanism’s standard set of analytic categories—entities, activities, and organization—should be expanded to include constraints and energetics. Not only is such an expansion required descriptively to capture research on molecular motors but, more importantly from a philosophical point of view, it enables a non-regressive account of activities in mechanisms. In other words, this expansion enables a philosophical account of mechanistic explanation that avoids a regress of entities and activities “all the way down.” Rather, mechanistic explanation bottoms out in constraints and energetics. (shrink)

Sexual selection drives the evolution of some of the most exaggerated traits in nature. Studies on sexual selection often focus on the size of these traits relative to body size, but few focus on energetic maintenance costs of the tissues that compose them, and the ways in which these costs vary with body size. The relationships between energy use and body size have consequences that may allow large individuals to invest disproportionally more in sexually selected structures, or lead to (...) the reduced per‐gram maintenance cost of enlarged structures. Although sexually selected traits can incur energetic maintenance costs, these costs are not universally high; they are dependent on the relative mass and metabolic activity of tissues associated with them. Energetic costs of maintenance may play a pervasive yet little‐explored role in shaping the relative scaling of sexually selected traits across diverse taxa. Also see the video abstract here: https://youtu.be/JyuoQIeA33Q. (shrink)

The brain displays both the anatomical features of a vast amount of interconnected topological mappings as well as the functional features of a nonlinear, metastable system at the edge of chaos, equipped with a phase space where mental random walks tend towards lower energetic basins. Nevertheless, with the exception of some advanced neuro-anatomic descriptions and present-day connectomic research, very few studies have been addressing the topological path of a brain embedded or embodied in its external and internal environment. Herein, (...) by using new formal tools derived from algebraic topology, we provide an account of the metastable brain, based on the neuro-scientific model of Operational Architectonics of brain-mind functioning. We introduce a “topodynamic” description that shows how the relationships among the countless intertwined spatio-temporal levels of brain functioning can be assessed in terms of projections and mappings that take place on abstract structures, equipped with different dimensions, curvatures and energetic constraints. Such a topodynamical approach, apart from providing a biologically plausible model of brain function that can be operationalized, is also able to tackle the issue of a long-standing dichotomy: it throws indeed a bridge between the subjective, immediate datum of the naïve complex of sensations and mentations and the objective, quantitative, data extracted from experimental neuro-scientific procedures. Importantly, it opens the door to a series of new predictions and future directions of advancement for neuroscientific research. (shrink)

Features of gait are determined at multiple levels, from the selection of the gait itself (e.g. walk or run) through the specific parameters utilized (stride length, frequency, etc.) to the pattern of muscular excitation. The ultimate choices are neurally determined, but what is involved with that decision process? Human locomotion appears stereotyped not so much because the pattern is predetermined, but because these movement patterns are good solutions for providing movement utilizing the machinery available to the individual (the legs and (...) their requisite components). Under different circumstances the appropriate solution may differ broadly (different gait) or subtly (different parameters). Interpretation of the neural decision making process would benefit from understanding the influences that determine the selection of the appropriate solution in any set of circumstances, including that of normal conditions. In this review we survey an array of studies that point to energetic cost as a key input to the gait coordination system, and not just an outcome of the gait pattern implemented. We then use that information to rigorously define the construct proposed by Sparrow and Newell (1998) where the effects of environment, organism and task act as constraints determining the solution set available, and the coordination pattern is then implemented under a pressure for energetic economy. Environment is defined in terms of affordances based on the ecological psychology definition of the concept and organism is defined as classic morphology and physiology based capabilities. We rely on a novel conceptualization of task that recognizes that the task goal needs to be separated from the mechanisms that achieve the goal if the motivation behind the selection of the mechanism strategy is to be exposed and understood. This reformulation of the Sparrow and Newell construct is then linked to the proposed pressure for economy by considering it as an optimization problem, where the most readily selected gait strategy will be that which achieves the task goal at (or near) the energetic minimum. (shrink)

The properties of disulphide bonds relevant to their roles in stabilizing protein conformation are reviewed. Natural disulphides can stabilize folded conformations substantially, in some cases to much greater extents than would be expected from just entropic effects on the unfolded state. The linkage relationship between conformational stability and disulphide stability is illustrated. Disulphides will not, however, increase protein stability if the disulphides are not maintained in the unfolded state or if instability is caused by processes, such as chemical modification or (...) proteolysis, that are not linked to unfolding, either local or global. This is part of the reason why some recent attempts to increase protein stability by introducing new disulphides have had only modest success. Other reasons appear to be the severe energetic constraints on disulphide bond geometry and, in some cases, unfavourable effects of introducing Cys residues by mutation. (shrink)

This essay presents a scenario of the origin of life that is based on analysis of biological architecture and mechanical design at the microstructural level. My thesis is that the same architectural and energetic constraints that shape cells today also guided the evolution of the first cells and that the molecular scaffolds that support solid-phase biochemistry in modern cells represent living microfossils of past life forms. This concept emerged from the discovery that cells mechanically stabilize themselves using tensegrity (...) architecture and that these same building rules guide hierarchical self-assembly at all size scales (Sci Amer 278:48–57;1998). When combined with other fundamental design principles (e.g., energy minimization, topological constraints, structural hierarchies, autocatalytic sets, solid-state biochemistry), tensegrity provides a physical basis to explain how atomic and molecular elements progressively self-assembled to create hierarchical structures with increasingly complex functions, including living cells that can self-reproduce. BioEssays 22:1160–1170, 2000. © 2000 John Wiley & Sons, Inc. (shrink)

Spontaneous brain activity has received increasing attention as demonstrated by the exponential rise in the number of published papers on this topic over the last thirty years. Such “intrinsic” brain activity, generated in the absence of an explicit task, is frequently associated with resting-state or default-mode networks. The focus on characterizing spontaneous brain activity promises to shed new light on questions concerning the structural and functional architecture of the brain and how they are related to “mind”. However, many critical questions (...) have yet to be addressed. In this review, we focus on a scarcely explored area, specifically the energetic requirements and constraints of spontaneous activity, taking into account both thermodynamical and informational perspectives. We argue that the “classical” definitions of spontaneous activity do not take into account an important feature, that is, the critical thermodynamic energetic differences between spontaneous and evoked brain activity. Spontaneous brain activity is associated with slower oscillations compared with evoked, task-related activity, hence it exhibits lower levels of enthalpy and “free-energy” (i.e. the energy that can be converted to do work), thus supporting noteworthy thermodynamic energetic differences between spontaneous and evoked brain activity. Increased spike frequency during evoked activity has a significant metabolic cost, consequently, brain functions traditionally associated with spontaneous activity, such as mind wandering, require less energy that other nervous activities. We also review recent empirical observations in neuroscience, in order to capture how spontaneous brain dynamics and mental function can be embedded in a non-linear dynamical framework, which considers nervous activity in terms of phase spaces, particle trajectories, random walks, attractors and/or paths at the edge of the chaos. This takes us from the thermodynamic free-energy, to the realm of “variational free-energy”, a theoretical construct pertaining to probability and information theory which allows explanation of unexplored features of spontaneous brain activity. (shrink)

Perhaps in last few centuries not any big theory has resulted in so much opposition as Darwinian theory of evolution. Within this theory, claim that _Homo sapiens _evolved from animal ancestors, namely apes, is undoubtedly the most controversial issue. Long tradition of teaching by Church that a pair of first people was created in short time in Eden Garden is in contradiction to discoveries of biology, including paleontology. If God exists, which is not the research subject of science, he created (...) human beings by a long process of biological Darwinian evolution followed by shorter process of non-Darwinian cultural evolution. Biologist must treat _Homo sapiens _as just one more species with long phylogeny, albeit special species characterized by brains of enormous size, with well-developed neocortex and very special mental traits being the consequence of such brain. The paper considers selection forces toward increase of this extremely expensive organ, draining at least 20% of energy. The main idea is that a series of positive feedbacks were responsible for the development of brain, correlated increase of intelligence and development of culture. Although no great breakthrough is required for such mode of evolution, energetic constrain limiting brain size was present through large part of our evolution, which was first broken by using primitive tools for cutting meat and grinding down seeds, then by thermal processing of food. The new constrain on skull size, and correlated brain size, that is the danger of death of both mother and child during childbirth, has been partly relieved by shifting large part of brain development to postnatal period. Resulting very long childhood was a prerequisite to cultural development of our species. (shrink)

Aerobic mitochondria serve as the power sources of eukaryotes by producing ATP through oxidative phosphorylation (OXPHOS). The enzymes involved in OXPHOS are multisubunit complexes encoded by both nuclear and mitochondrial DNA. Thus, regulation of respiration is necessarily a highly coordinated process that must organize production, assembly and function of mitochondria to meet an organism's energetic needs. Here I review the role of OXPHOS in metabolic adaptation and diversification of higher animals. On a physiological timescale, endocrine‐initiated signaling pathways allow organisms (...) to modulate respiratory enzyme concentration and function under changing environmental conditions. On an evolutionary timescale, mitochondrial enzymes are targets of natural selection, balancing cytonuclear coevolutionary constraints against physiological innovation. By synthesizing our knowledge of biochemistry, physiology and evolution of respiratory regulation, I propose that we can now explore questions at the interface of these fields, from molecular translation of environmental cues to selection on mitochondrial haplotype variation. BioEssays 28: 890–901, 2006. © 2006 Wiley periodicals, Inc. (shrink)

A sustainable system has all the essential characteristics of an organism?an irreducible whole that develops, maintains and reproduces, or renews, itself by mobilizing material and energy captured from the environment. What is the nature of the material and energy mobilization that makes an organism? I begin with a brief description of a tentative theory of the organism?developed in detail elsewhere (Ho, 1993; 1994a; 1995a,b; 1996b,c)?as a dynamically and energetically closed domain of cyclic non?dissipative processes coupled to irreversible dissipative processes, which (...) effectively frees the organism from thermodynamic constraints so that it is poised for rapid, specific intercommunication, enabling it to function as a coherent whole. I shall then show how this novel theoretical framework may begin to provide normative criteria for sustainable economic systems, thereby also exposing some of the inadequacies of current models and assumptions. (shrink)

Owing in part to Rorty’s energetic promotional efforts, Davidson’s philosophy of language has received much attention in recent decades from quarters most diverse, creating at times a sense of an almost protean versatility. Conspicuously missing from the rapidly growing literature on the subject is a sustained discussion of the relationship between Davidson’s interpretive theory and history: an omission all the more surprising since a comparison between Davidson and Gadamer has been pursued at some length and now, it seems,abandoned—all without (...) as much as a mention of history, which does, of course,play a prominent role in Gadamer’s thought. The issue, moreover, is hardly negligible. Davidson understood his work as an attempt to reconcile the demands of rigorous naturalism with the Kantian picture of human rationality,thereby salvaging what he considered to be important and interesting features of the human world from mechanistic reduction. For many thinkers of the 20th century, including Dewey and Gadamer, the irreducibly human had to do with the historical being of mankind, with historicity as the unique mark of our species. Yet, Davidson has virtually nothing to say about history and, in fact, a recent study by Giuseppina D’Oro (2004b), comparing Collingwood and Davidson, concludes that Davidson’s model of interpretation results in a distorted picture of understanding, as judged by the standards of a historically informed interpretive practice. Examining the causes of their disagreement, then,should help us make some headway towards a clearer sense of what it means to understand historically, by gleaning some additional constraints that the requirement of historicity imposes upon an interpretive theory. We start with D’Oro’s criticism of Davidson and discuss the alternative account of interpretation she proposes. Afterwards, we turn to Collingwood to see if either account does justice to his central insights, ending with some suggestions about the conceptual adjustments required to accommodate them. (shrink)

The brain's reliance on glucose as a primary fuel source is well established, but psychological models of cognitive processing that take energy supply into account remain uncommon. One exception is research on self-control depletion, where debate continues over a limited-resource model of self-control depletion. This model argues that transient reduction in self-control after exertion of prior self-control is caused by the depletion of brain glucose, and that self-control processes are special, perhaps unique, in this regard. This model has been argued (...) to be physiologically implausible in several recent reviews. This paper attempts to correct some inaccuracies that have occurred during debate over the physiological plausibility of this model. We contend that not only is such limitation of cognition by constraints on glucose supply plausible, it is well established in the neuroscience literature across several cognitive domains. Conversely, we argue that there is no evidence that self-control is special in regard to its metabolic cost. Mental processes require physical energy, and the body is limited in its ability to supply the brain with sufficient energy to fuel mental processes. This article reviews current findings in brain metabolism and seeks to resolve the current conflict in the field regarding the physiological plausibility of the self-control glucose-depletion hypothesis. (shrink)

This volume presents a collection of refereed papers reflecting the state of the art in the area of over-constrained systems. Besides 11 revised full papers, selected from the 24 submissions to the OCS workshop held in conjunction with the First International Conference on Principles and Practice of Constraint Programming, CP '95, held in Marseilles in September 1995, the book includes three comprehensive background papers of central importance for the workshop papers and the whole field. Also included is an introduction by (...) one of the volume editors together with a bibliography listing 243 entries. All in all this is a very useful reference book relevant for all researchers and practitioners interested in hierarchical, partial, and over-constrained systems. (shrink)

This article argues that Bernard Williams’ Critical Theory Principle (CTP) is in tension with his realist commitments, i.e., deriving political norms from practices that are inherent to political life. The Williamsian theory of legitimate state power is based on the central importance of the distinction between political rule and domination. Further, Williams supplements the normative force of his theory with the CTP, i.e., the principle that acceptance of a justification regarding power relations ought not to be created by the very (...) same coercive power. I contend that the CTP is an epistemic criterion of reflective (un)acceptability which is not strictly connected to the question of whether people are dominated or not. I show that there are cases of non-domination that fail the epistemic requirements of the CTP. (shrink)

What role, if any, does formal logic play in characterizing epistemically rational belief? Traditionally, belief is seen in a binary way - either one believes a proposition, or one doesn't. Given this picture, it is attractive to impose certain deductive constraints on rational belief: that one's beliefs be logically consistent, and that one believe the logical consequences of one's beliefs. A less popular picture sees belief as a graded phenomenon.

Teresa Brennan was born in 1952 in Australia and died in South Florida, following a hit-and-run car accident in December 2002. In the ten years between her doctorate and her death, Brennan published five monographs, the most famous posthumously. The Transmission of Affect begins with a question that readers often remember: “Is there anyone who has not, at least once, walked into a room and ‘felt the atmosphere’?” Here and throughout her work, Brennan challenges the self-contained subject of Western modernity, (...) whose affects are presumed to be possessions of that self, underscoring the historical emergence of this egoic construction.I never met Teresa Brennan; I did not know her name until a decade after she... (shrink)

The debate on probabilistic measures of coherence flourishes for about 15 years now. Initiated by papers that have been published around the turn of the millennium, many different proposals have since then been put forward. This contribution is partly devoted to a reassessment of extant coherence measures. Focusing on a small number of reasonable adequacy constraints I show that (i) there can be no coherence measure that satisfies all constraints, and that (ii) subsets of these adequacy constraints (...) motivate two different classes of coherence measures. These classes do not coincide with the common distinction between coherence as mutual support and coherence as relative set-theoretic overlap. Finally, I put forward arguments to the effect that for each such class of coherence measures there is an outstanding measure that outperforms all other extant proposals. One of these measures has recently been put forward in the literature, while the other one is based on a novel probabilistic measure of confirmation. (shrink)

Neuroscience constrains psychology, but stating these constraints with precision is not simple. Here I consider whether mechanistic analysis provides a useful way to integrate models of cognitive and neural structure. Recent evidence suggests that cognitive systems map onto overlapping, distributed networks of brain regions. These highly entangled networks often depart from stereotypical mechanistic behaviors. While this casts doubt on the prospects for classical mechanistic integration of psychology and neuroscience, I argue that it does not impugn a realistic interpretation of (...) either type of model. Cognitive and neural models may depict different, but equally real, causal structures within the mind/brain. (shrink)

At the bottom of all human activities are “values,” the conviction that some things “ought to be” and others not. Science, however, with its immense interest in mere facts seems to lack all understanding of such‘requiredness.’… A science … which would seriously admit nothing but indifferent facts … could not fail to destroy itself.

The Zhuangzi, a 4th century BCE Chinese text, is optimistic about life unrestrained by entrenched values. This paper contributes to existing debates on Zhuangzian freedom in three ways. First, it reflects on how it is possible to enjoy the freedom envisaged in the Zhuangzi. Many discussions welcome the Zhuangzi’s picture of release from life shaped by canonical visions, without also giving thought to life without these driving visions. Consider this scenario: in a world with limitless possibilities, would it not be (...) fraught, not knowing how to interpret situations? I suggest that freedom in the Zhuangzi is possible only if one succeeds in reorienting herself to the new ‘normal’. Second, I introduce and develop the idea of working with constraints. This focuses on an agent's maximizing the fit between relevant conditions, on the one hand, and their capabilities, on the other. Finally, I propose that self-directed practice, an important expression of agency, is required for building capabilities that enable such freedom. I examine the idea of risk involved in these firsthand experiences, articulating an account of agency that sits at the heart of hard-won Zhuangzian freedom. (shrink)

How linguistic structures evolve so as to become easier to process is addressed by Isbilen and Christiansen for the Now‐or‐Never bottleneck. The authors suggest that this fundamental challenge in language processing is coped with by rapid compression of the transient linguistic input into chunks then to be passed on. As linguistic structures that can be chunked more easily tend to stabilize and proliferate, language evolves to fit learners’ cognitive capabilities.

In non-causal explanations, some non-causal facts (such as mathematical, modal or metaphysical) are used to explain some physical facts. However, precisely because these explanations abstract away from causal facts, they face two challenges: 1) it is not clear why would one rather than the other non-causal explanantia be relevant for the explanandum; and 2) why would standing in a particular explanatory relation (e.g., “counterfactual dependence”, “constraint”, “entailment”, “constitution”, “grounding”, and so on), and not in some other, be explanatory. I develop (...) an explanatory relevance account which is based on erotetic constraints and show how it addresses these two challenges. (shrink)

In this paper, I discuss the main difficulties one encounters whensolving problems with inconsistent constraints. I argue that in order to meetthese difficulties we need an inconsistency-adaptive logic that enables one toderive as many consequences as possible, but that at the sametime allows one to determine which consequences can be accepted. I showthat the inconsistency-adaptive logic ANA satisfies these requirements.

Christian Quast has recently embarked on the project of systematizing the debate about the notion of expertise, an extremely fascinating and important issue addressed by scholars of many disciplines yet still in need of an interdisciplinary take. He sheds light on a number of relevant features of this notion and defends what he calls a “balanced” account of expertise, namely one that defines this concept in light of an expert’s dispositions, manifestations of their dispositions, and social role or function. In (...) this critical reply, I offer some considerations that put pressure on Quast’s balanced account and hopefully help anyone interested in this debate take a step forward toward explaining what it takes for one to be an expert. The reply is structured as follows. First, I argue that his allegedly balanced view is liable to a potentially compromising tension between its function component and the ingredients of objective expertise (§1). Then, I show that Quast’s threefold characterization of an objective expert is too strong, as it imposes conditions that several individuals whom we would consider experts are unable to fulfill (§2). Finally, I provide reasons in favor of endorsing an objective account of expertise in light of some specific features of our society and show how this account can take into due consideration the different services experts ordinarily perform (§3). (shrink)

Abstract: In earlier work, I argued that individuals have a right to own firearms for personal defense, and that as a result, gun prohibition would be unjustified unless it at least produced benefits many times greater than its costs. Here, I defend that argument against objections posed by Nicholas Dixon and Jeff McMahan to the effect that the right of citizens to be free from gun violence counterbalances the right of self-defense, and that gun prohibition does not violate the right (...) of self-defense because it renders everyone overall safer. (4258 words). (shrink)

The Zhuangzi, a 4th century BCE Chinese text, is optimistic about life unrestrained by entrenched values. This paper contributes to existing debates on Zhuangzian freedom in three ways. First, it reflects on how it is possible to enjoy the freedom envisaged in the Zhuangzi. Many discussions welcome the Zhuangzi’s picture of release from life shaped by canonical visions, without also giving thought to life without these driving visions. Consider this scenario: in a world with limitless possibilities, would it not be (...) fraught, not knowing how to interpret situations? I suggest that freedom in the Zhuangzi is possible only if one succeeds in reorienting herself to the new ‘normal’. Second, I introduce and develop the idea of working with constraints. This focuses on an agent's maximizing the fit between relevant conditions, on the one hand, and their capabilities, on the other. Finally, I propose that self-directed practice, an important expression of agency, is required for building capabilities that enable such freedom. I examine the idea of risk involved in these firsthand experiences, articulating an account of agency that sits at the heart of hard-won Zhuangzian freedom. (shrink)

In earlier work, I argued that gun prohibition is unjustified because it violates an individual right to self-defense. Here, I defend that argument against objections posed by Nicholas Dixon and Jeff McMahan to the effect that the right of citizens to be free from gun violence counterbalances the right of self-defense, and that gun prohibition does not violate the right of self-defense because it renders everyone overall safer.

Cosmopolitan education aims to transmit cosmopolitan forms of life in order to participate morally in the world community. The primary characteristics of this cosmopolitan education are its acceptance of the shared humanity of all persons as a fact of human existence and as a motivating guide for human interaction, and the requirement of democratic inclusion in deliberations of the governance of those interactions, including morality. Such an education in cosmopolitan morality requires means that befit its core components. This paper contrasts (...) the concepts of strict and moderate cosmopolitanism, empirical and deliberative morality, and structural and dispositional cosmopolitanism to show that the moderate, inclusive and deliberative processes of deliberative dispositional cosmopolitanism are more suited to cosmopolitan education in morality than strong, empirical-focused structural cosmopolitan efforts. Though strong, structural and empirically based forms may be more likely to guarantee preferred outcomes in the learning of specific morals or the implementation of institutional norms, they are also more likely to run afoul of the core components of cosmopolitanism because they will privilege outcomes over processes, and are thus more likely to be less inclusive and more coercive. In contrast, and even though they are less certain to guarantee preferred moral outcomes or actions, moderate, deliberative dispositional forms of cosmopolitan education embody the morality they seek to inform, and are more likely to find sustained internalised support over time. (shrink)

Although military personnel are required to follow all legal orders, morally the traditional contract between soldier and state rests on shared assumptions about the purposes for which national militaries will and will not be used.