This is a thorough treatment of first-order modal logic. The book covers such issues as quantification, equality (including a treatment of Frege's morning star/evening star puzzle), the notion of existence, non-rigid constants and function symbols, predicate abstraction, the distinction between nonexistence and nondesignation, and definite descriptions, borrowing from both Fregean and Russellian paradigms.

The variety of semantical approaches that have been invented for logic programs is quite broad, drawing on classical and many-valued logic, lattice theory, game theory, and topology. One source of this richness is the inherent non-monotonicity of its negation, something that does not have close parallels with the machinery of other programming paradigms. Nonetheless, much of the work on logic programming semantics seems to exist side by side with similar work done for imperative and functional programming, with relatively minimal (...) contact between communities. In this paper we summarize one variety of approaches to the semantics of logic programs: that based on fixpoint theory. We do not attempt to cover much beyond this single area, which is already remarkably fruitful. We hope readers will see parallels with, and the divergences from the better known fixpoint treatments developed for other programming methodologies. (shrink)

In an earlier paper, [5], I gave semantics and tableau rules for a simple firstorder intensional logic called FOIL, in which both objects and intensions are explicitly present and can be quantified over. Intensions, being non-rigid, are represented in FOIL as (partial) functions from states to objects. Scoping machinery, predicate abstraction, is present to disambiguate sentences like that asserting the necessary identity of the morning and the evening star, which is true in one sense and not true in another.In this (...) paper I address the problem of axiomatizing FOIL. I begin with an interesting sublogic with predicate abstraction and equality but no quantifiers. In [2] this sublogic was shown to be undecidable if the underlying modal logic was at least K4, though it is decidable in other cases. The axiomatization given is shown to be complete for standard logics without a symmetry condition. The general situation is not known. After this an axiomatization for the full FOIL is given, which is straightforward after one makes a change in the point of view. (shrink)

This book describes computability theory and provides an extensive treatment of data structures and program correctness. It makes accessible some of the author's work on generalized recursion theory, particularly the material on the logic programming language PROLOG, which is currently of great interest. Fitting considers the relation of PROLOG logic programming to the LISP type of language.

There is an error in the completeness proof for the {λ, =} part of FOIL-K. The error occurs in Section 4, in the text following the proof of Corollary 4.7, and concerns the definition of the interpretation I on relation symbols. Before this point in the paper, for each object variable v an equivalence class v has been defined, and for each intension variable f a function f has been defined. Then the following definition is given for a relation symbol (...) P : v1, v2, . . . , f1, f2, . . . ∈ I(P )(Γ) just in case there are w1, w2, . . . in d(Γ) with wi ∈ vi such that P (w1, w2, . . . , f1, f2, . . .) ∈ Γ. It was pointed out by Torben Brauner that we could have f1 and g1 being the same function, but also have P (w1, w2, . . . , f1, f2, . . .) ∈ Γ without having P (w1, w2, . . . , g1, f2, . . .) ∈ Γ. Our solution is to modify the definition of the model, rather artificially, so that if f and g are the same function, then f and g are syntactically the same intension variable. This is done as follows. First, arbitrarily choose some object variable w, and its corresponding equivalence class w. For each intension variable f we define a disambiguation world ˆ. (shrink)

Recording and manipulating neuronal ensemble activity is a key requirement in advanced neuromodulatory and behavior studies. Devices capable of both recording and manipulating neuronal activity brain-computer interfaces should ideally operate un-tethered and allow chronic longitudinal manipulations in the freely moving animal. In this study, we designed a new intracortical BCI feasible of telemetric recording and stimulating local gray and white matter of visual neural circuit after irradiation exposure. To increase the translational reliance, we put forward a Göttingen minipig model. The (...) animal was stereotactically irradiated at the level of the visual cortex upon defining the target by a fused cerebral MRI and CT scan. A fully implantable neural telemetry system consisting of a 64 channel intracortical multielectrode array, a telemetry capsule, and an inductive rechargeable battery was then implanted into the visual cortex to record and manipulate local field potentials, and multi-unit activity. We achieved a 3-month stability of the functionality of the un-tethered BCI in terms of telemetric radio-communication, inductive battery charging, and device biocompatibility for 3 months. Finally, we could reliably record the local signature of sub- and suprathreshold neuronal activity in the visual cortex with high bandwidth without complications. The ability to wireless induction charging combined with the entirely implantable design, the rather high recording bandwidth, and the ability to record and stimulate simultaneously put forward a wireless BCI capable of long-term un-tethered real-time communication for causal preclinical circuit-based closed-loop interventions. (shrink)

In this paper I discuss recent debates concerning etiological theories of functions. I defend an etiological theory against two criticisms, namely the ability to account for malfunction, and the problem of structural doubles. I then consider the arguments provided by Bigelow and Pargetter (1987) for a more forward looking account of functions as propensities or dispositions. I argue that their approach fails to address the explanatory problematic for which etiological theories were developed.

IntroductionRegular exercise has long been shown to positively impact the immune system responsiveness and improve mental well-being. However, the putative links between biomarkers of mental health and immune efficiency in exercising subjects have been scarcely investigated. The aim of this study was to verify the effect of a 14-week combined chair-based exercise program on salivary steroid hormones and anti-microbial proteins, functional fitness, and MWB indexes in pre-frail older women.MethodsThe participant women were randomly divided into the exercising group and the (...) non-exercising control group. The pre/post assessment included: salivary anti-microbial proteins lysozyme; and immunoglobulin-A ; salivary steroid hormones of testosterone and cortisol ; functional fitness ; MWB questionnaires.ResultsSignificant differences with large Cohen’s effect sizes were found on increased salivary TT after exercise intervention. The results revealed a decrease in IgA levels after CEP. The increase in subjective happiness levels and decrease of stress perception and depressive state were found after intervention in the CEP group. Robust statistical differences in gait speed and balance tests were also found in the CEP group. In control, COR increased moderately while no changes were found for the other indicators. Correlation analyses showed inter-dependence between pre–post variations of MWB, biochemical indexes, and fitness function.ConclusionThe CEP program was able to improve functional-fitness performance, decrease feelings of stress, and increase happiness. The CEP also induced clinically relevant hormonal and immune responses, which suggests that chair exercises that combine muscular strength, balance, and gait speed training are promising interventions to improve physical and mental health of older pre-frail adults. (shrink)

According to historical theories of biological function, a trait's function is determined by natural selection in the past. I argue that, in addition to historical functions, ahistorical functions ought to be recognized. I propose a theory of biological function which accommodates both. The function of a trait is the way it contributes to fitness and fitness can only be determined relative to a selective regime. Therefore, the function of a trait can only be specified relative to a selective regime. Apart (...) from its desirable pluralism, only this view of relational function can support the function/accident and function/malfunction distinctions commonly thought to be part of the concept of function. Furthermore, only relational function correctly characterizes the explanatory consequences of function attributions in evolutionary biology. (shrink)

It’s recently been argued that biological fitness can’t change over the course of an organism’s life as a result of organisms’ behaviors. However, some characterizations of biological function and biological altruism tacitly or explicitly assume that an effect of a trait can change an organism’s fitness. In the first part of the paper, I explain that the core idea of changing fitness can be understood in terms of conditional probabilities defined over sequences of events in an organism’s life. The result (...) is a notion of “conditional fitness” which is static but which captures intuitions about apparent behavioral effects on fitness. The second part of the paper investigates the possibility of providing a systematic foundation for conditional fitness in terms of spaces of sequences of states of an organism and its environment. I argue that the resulting “organism–environment history conception” helps unify diverse biological perspectives, and may provide part of a metaphysics of natural selection. (shrink)

Historically, male sexual fitness was framed by a patriarchal politics of life centred on regeneration, population and nation. In the later 20th century, as successful ageing became promoted by the lifestyle practices of an idealized healthy and active senior citizenry, traditional gerontocratic power over the sexual risks of youth gave way to a medical sexology concerned with sexual functionality across the lifecourse; in particular, erectility. Recently, erectile dysfunction has expanded to become a population-wide health problem with increasingly refined diagnoses based (...) on `phases', `early warning signs' and preventative regimes, especially as Viagra has become so widely available. This article explores a new bodily configuration in the making; arising, on the one hand, from the pharmacological and scientific technologization of male sexuality, and, on the other, from a contemporary politics of life that both contests the late-life ageism of the past and fosters a mid-life ageism in the present. (shrink)

Historically, male sexual fitness was framed by a patriarchal politics of life centred on regeneration, population and nation. In the later 20th century, as successful ageing became promoted by the lifestyle practices of an idealized healthy and active senior citizenry, traditional gerontocratic power over the sexual risks of youth gave way to a medical sexology concerned with sexual functionality across the lifecourse; in particular, erectility. Recently, erectile dysfunction has expanded to become a population-wide health problem with increasingly refined diagnoses based (...) on `phases', `early warning signs' and preventative regimes, especially as Viagra has become so widely available. This article explores a new bodily configuration in the making; arising, on the one hand, from the pharmacological and scientific technologization of male sexuality, and, on the other, from a contemporary politics of life that both contests the late-life ageism of the past and fosters a mid-life ageism in the present. (shrink)

Traditionally, the sense of touch—alongside the senses of taste and smell—has been excluded from the aesthetic domain. These proximal modalities are thought to deliver only sensory pleasures, not the complex, world-directed perceptual states that characterize aesthetic experience. In this paper, I argue that this tradition fails to recognize the perceptual possibilities of haptic touch, which allows us to experience properties of the objects with which we make bodily contact, including their weight, shape, solidity, elasticity, and smoothness. These features, moreover, may (...) be indicative of how well-suited an object is for its function, and in feeling them we can thus feel the positive aesthetic quality of functional beauty. (shrink)

Fitness in the sense of actual rate of increase of genotypes, commonly used in population genetics, is contrasted with fitness in the ordinary sense (and Darwin's) of adaptedness of organisms. Fitness as actual reproductive success is interpreted as a function of variables representing intrinsic adaptive capacities and environmental properties. Adaptive capacities causally contribute to fitness as actual reproductive success which in turn, as relative increase of genotypes, determines evolutionary change. The propensity interpretation of fitness is shown not to play a (...) role in evolutionary explanation. (shrink)

ABSTRACTBeing able to resist temptation at a young age is crucial for successful functioning yet it can be challenging. According to the Selection, Optimization, and Compensation with Emotion Regulation framework, one central element of successful functioning is selection which involves choosing among regulatory options whose resource requirements fits with the amount of available resources an individual possesses. Although conceptually important, direct empirical evidence is lacking. Accordingly, the present study utilised performance based measures to examine the interactive effect of regulatory selection (...) to resist temptation, and individual differences in executive resources, on functioning in young children. Specifically, 39 first grade children that varied in executive resources, selected between two major regulatory strategies to resist temptation, that varied in their resource demands, and were evaluated on successful functioning... (shrink)

Recent attempts to clarify the fitness in evolutionary theory as a propensity (Brandon 1978; Brandon and Beatty 1984; Burian 1983; Mills and Beatty 1979; Sober 1984a, 1984b) or as a primitive theoretical term (Rosenberg 1983, 1985; Williams 1970, Williams and Rosenberg 1985) all miss the mark in clarifying the empirical content and explanatory power of natural selection theory.I shall argue that the crucial distinction missing in these accounts is between the sense of fitness common in population genetics as actual relative (...) rate of increase of genotypes and fitness in the more ordinary sense--and Darwin’s--of adaptedness of organisms. The relation between these senses of ‘fitness’ is that fitness as actual reproduction success depends on, is a function of, variables representing adaptive capacities and environmental properties. (shrink)

Cascades of transcriptional regulation are the common source of the forward drive in all developmental systems. Increases in complexity and specificity of gene expression at successive stages are based on the collaboration of varied combinations of transcription factors already expressed in the cells to turn on new genes, and the logical relationships between the transcription factors acting and becoming newly expressed from stage to stage are best visualized as gene regulatory networks. However, gene regulatory networks used in different developmental contexts (...) underlie processes that actually operate through different sets of rules, which affect the kinetics, synchronicity, and logical properties of individual network nodes. Contrasting early embryonic development in flies and sea urchins with adult mammalian hematopoietic development from stem cells, major differences are seen in transcription factor dosage dependence, the silencing or damping impacts of repression, and the impact of cellular regulatory history on the parts of the genome that are accessible to transcription factor action in a given cell type. These different features not only affect the kinds of models that can illuminate developmental mechanisms in the respective biological systems, but also reflect the evolutionary needs of these biological systems to optimize different aspects of development. (shrink)

This research topic (RT) focused on the impact of fitness on cognitive function and development in adolescents and elderly adults from the standpoint of lifespan neuroscience. Adolescent brain development is characterized by multimodal integration of brain anatomical features and function, according to accumulating evidence. The elderly, on the other hand, suffer from age-related cognitive deterioration. Fitness may be a major factor influencing brain growth and cognitive performance throughout these two critical times for neurological development. It is a multidimensional notion that (...) includes cardiovascular fitness, muscular strength and endurance, flexibility, and body composition, as well as motor fitness (balance, agility, speed, power, and coordination). Adolescents and older people may be responsive to intervention trials aimed at improving fitness levels, such as outdoor activities, cardiovascular exercise, and mind-body practice since brain network integration and neural efficiency are rapidly altered during this period. This RT investigates how fitness influences structural and functional brain development, particularly cognitive functions, and emotional health in adolescents and elderly people, as well as training strategies that may assist cognitive progress throughout this time. It includes a clinical trial (1) and original research papers (4) on the influence of fitness on cognitive function and development in adolescents and elderly adults from a lifespan neu... (shrink)

It is widely accepted that the way information transfers across networks depends importantly on the structure of the network. Here, we show that the mechanism of information transfer is crucial: in many respects the effect of the specific transfer mechanism swamps network effects. Results are demonstrated in terms of three different types of transfer mechanism: germs, genes, and memes. With an emphasis on the specific case of transfer between sub-networks, we explore both the dynamics of each of these across networks (...) and a measure of their comparative fitness. Germ and meme transfer exhibit very different dynamics across linked networks. For germs, measured in terms of time to total infection, network type rather than degree of linkage between sub-networks is the primary factor. For memes or belief transfer, measured in terms of time to consensus, it is the opposite: degree of linkage trumps network type in importance. The dynamics of genetic information transfer is unlike either germs or memes. Transfer of genetic information is robust across network differences to which both germs and memes prove sensitive. We also consider function: how well germ, gene, and meme transfer mechanisms can meet their respective objectives of infecting the population, mixing and transferring genetic information, and spreading a message. A shared formal measure of fitness is introduced for purposes of comparison, again with an emphasis on linked sub-networks. Meme transfer proves superior to transfer by genetic reproduction on that measure, with both memes and genes superior to infection dynamics across all networks types. What kinds of network structure optimize fitness also differ among the three. Both germs and genes show fairly stable fitness with added links between sub-networks, but genes show greater sensitivity to the structure of sub-networks at issue. Belief transfer, in contrast to the other two, shows a clear decline in fitness with increasingly connected networks. When it comes to understanding how information moves on networks, our results indicate that questions of information dynamics on networks cannot be answered in terms of networks alone. A primary role is played by the specific mechanism of information transfer at issue. We must first ask about how a particular type of information moves. (shrink)

Understanding the dynamics of information is crucial to many areas of research, both inside and outside of philosophy. Using computer simulations of three kinds of information, germs, genes, and memes, we show that the mechanism of information transfer often swamps network structure in terms of its effects on both the dynamics and the fitness of the information. This insight has both obvious and subtle implications for a number of questions in philosophy, including questions about the nature of information, whether there (...) is genetic information, and how to arrange scientific communities. (shrink)

We suggest that morbid jealousy falls on the extreme end of a jealousy continuum. Thus, many features associated with normal jealousy will be present in individuals diagnosed with morbid jealousy. We apply Boyer & Lienard's (B&L's) prediction one (P1; target article, sect. 7.1) to morbid jealousy, suggesting that fitness-related life-cycle dimensions predict sensitivity to cues, and frequency, intensity, and content of intrusive thoughts of partner infidelity. (Published Online February 8 2007).

Strong recent selection for social cognition may well explain the persistence of genes that predispose to schizophrenia. The specific mechanism responsible may be a skewed fitness function in which selection pushes the mean for advantageous mental traits perilously close to a “fitness cliff” where the system fails catastrophically in some individuals.

The preceding five years have brought remarkable advances in our understanding of the primary structure of drug receptors. The roles of certain amino acid residues in binding drugs and effecting receptor function have been proposed. As even more detailed structures become available, the goal of rational design of drug molecules based on predicted fits between the drug and its receptor will be near at hand. Although none of the classical receptors has yet yielded to X‐ray crystallographic analysis, the methods of (...) molecular biology facilitate the production of the large amounts of these rare proteins necessary for crystallization. Receptor proteins share one fundamental characteristic with allosterically regulated enzymes. Both have the structural flexibility that allows information to be transmitted to distant parts of the molecule. We will discuss recent observations about receptor structure and the dynamic nature of drug receptors, and pose questions about the significance of receptor dynamics for drug design. (shrink)

ABSTRACT This paper explores the role of aesthetic judgements in mathematics by focussing on the relationship between the epistemic and aesthetic criteria employed in such judgements, and on the nature of the psychological experiences underpinning them. I claim that aesthetic judgements in mathematics are plausibly understood as expressions of what I will call ‘aesthetic-epistemic feelings’ that serve a genuine cognitive and epistemic function. I will then propose a naturalistic account of these feelings in terms of sub-personal processes of representing and (...) assessing the relation between cognitive processes and certain properties of the stimuli at which they are directed. (shrink)

The etiological account of teleological function is beset by several difficulties, which I propose to solve by grafting onto the etiological theory a subordinated goal-contribution clause. This approach enables us to ascribe neither too many teleofunctions nor too few; to give a unitary, one-clause analysis that works just as well for teleological functions derived from Darwinian evolution, as for those derived from human intention; and finally, to save the etiological theory from falsification, by explaining how, in spite of appearances, the (...) theory can allow for evolutionary function loss. (shrink)

The maintenance of cell size homeostasis has been studied for years in different cellular systems. With the focus on ‘what regulates cell size’, the question ‘why cell size needs to be maintained’ has been largely overlooked. Recent evidence indicates that animal cells exhibit nonlinear cell size dependent growth rates and mitochondrial metabolism, which are maximal in intermediate sized cells within each cell population. Increases in intracellular distances and changes in the relative cell surface area impose biophysical limitations on cells, which (...) can explain why growth and metabolic rates are maximal in a specific cell size range. Consistently, aberrant increases in cell size, for example through polyploidy, are typically disadvantageous to cellular metabolism, fitness and functionality. Accordingly, cellular hypertrophy can potentially predispose to or worsen metabolic diseases. We propose that cell size control may have emerged as a guardian of cellular fitness and metabolic activity. Cell size is intimately connected to metabolism and growth rate, which are influenced by mitochondrial activity and biophysical constraints. We discuss that cellular fitness is often cell-size dependent. While the current evidence relies largely on proliferating cells, this connection from cell size to fitness may also help explain metabolic diseases. (shrink)

Associations between cardiorespiratory fitness and brain health in healthy older adults have been reported using a variety of cardiorespiratory fitness estimates. Using commonly used methods to determine CRF, we assessed the relationship between CRFe and executive function performance. Healthy older adults, underwent three CRF tests: a Maximal Graded Exercise Test performed on a cycle ergometer, the Rockport Fitness Walking Test, and a Non-Exercise Prediction Equation. Executive function was assessed by a computerized cognitive assessment using an N-Back task and a Stroop (...) task. Multiple hierarchical regression analyses were conducted to assess the relationship between different CRFe and executive function performance. Regardless of age and education, cardiorespiratory fitness estimated from the Maximal Graded Exercise Test and the Rockport Fitness Walking Test was significantly associated with the global switch cost. All CRFe were associated with the interference cost. No association was observed between CRFe and local switching costs or the updating costs. In the present study, not all subcomponents of executive function were related to CRFe. Interestingly, the executive functions that were associated with CRFe are those that are known to be the most affected by aging. (shrink)

This chapter contains sections titled: Introduction Function and Malfunction Function and Evolution Function Based on Past Origins Biological Functions Based on the Distant Past: Natural Selection Fitness and Goal‐Contribution Accounts Neo‐Teleology Looking at the Present: Causal Roles and Functions Evolution Bites Back: Vindication of the Selectionist Approach Postscript: Counterpoint Acknowledgments Notes References.

This essay argues for two conclusions about functional beauty, as this notion has been understood by Parsons and Carlson in a recent book by the same name. First of all, it is argued that functional beauty either is not a distinct kind of beauty or that the members of this kind are not all and only instances of the property of looking fit. Second, it is argued that functional beauty is relative only to categories corresponding to essential (...) functions. The second conclusion contradicts what Parsons and Carlson write about functional beauty, but the first conclusion does not, since they agree that looking fit is not necessary for functional beauty. However, their agreement on this point is based on reasons that can be shown to be mistaken. Moreover, contrary to what Parsons and Carlson claim, looking fit can also be shown to be insufficient for functional beauty. (shrink)

We characterize a type of functional explanation that addresses why a homologous trait originating deep in the evolutionary history of a group remains widespread and largely unchanged across the group’s lineages. We argue that biologists regularly provide this type of explanation when they attribute conserved functions to phenotypic and genetic traits. The concept of conserved function applies broadly to many biological domains, and we illustrate its importance using examples of molecular sequence alignments at the intersection of evolution and cell (...) biology. We use these examples to show how the study of conserved functions can integrate knowledge of a trait’s causal effects on fitness and its history of natural selection without invoking adaptation. We also show how conserved function provides a novel basis for addressing objections against evolutionary functions raised by Robert Cummins. (shrink)

Aim: Participation in classroom physical activity breaks may improve children’s cognition, but few studies have involved adolescents. The primary aim of this study was to examine the effects of classroom-based resistance training with and without cognitive training on adolescents’ cognitive function.Methods: Participants were 97 secondary school students. Four-year 10 classes from one school were included in this four-arm cluster randomized controlled trial. Classes were randomly assigned to the following groups: sedentary control with no cognitive training, sedentary with cognitive training, resistance (...) training without cognitive training, and resistance training with cognitive training. Sessions varied in levels of both cognitive demand and resistance training and were administered three times per week for 4 weeks. Inhibition, cognitive flexibility, episodic memory, on-task behavior, and muscular fitness were assessed at baseline and post-test. Linear mixed models were used to examine changes within and between groups.Results: In comparison with the control group, episodic memory improved significantly in the resistance training without cognitive training group. There were no group-by-time effects for inhibition or cognitive flexibility. Classroom activity breaks both with and without cognitive demand improved participants’ on-task behavior in comparison with the control and sedentary group. The resistance training programs did not lead to improvements in muscular fitness.Conclusion: Participation in body weight resistance training without cognitive training led to selective improvements in episodic memory. No training effects were found for inhibition or cognitive flexibility. A longer study period may be necessary to induce improvements in muscular fitness and associated changes in inhibition and cognitive flexibility.Clinical Trial Registration:https://www.anzctr.org.au/ACTRN12621001341819.aspx, Australian New Zealand Clinical Trials Registry—ACTRN12621001341819. (shrink)

The concept of ‘semiotic fitting’ is what we provide as a model for the description and analysis of the diversity dynamics and nativeness in semiotic systems. One of its sources is the concept of ‘ecological fitting’ which was introduced by Daniel Janzen as the mechanism for the explanation of diversity in tropical ecosystems and which has been shown to work widely over the communities of various types. As different from the neo-Darwinian concept of fitness that describes reproductive success, ‘fitting’ describes (...) functional relations and aboutness. Diversity of a semiotic system is strongly dependent on the mutual fitting of agents of which the semiotic system consists. The focus on semiotic fitting means that, in the analysis of diversity, we pay particular attention to decision making, functional plasticity, recognition windows, the depth of interpretation of the agents, and the categories responsible for the structure of the semiotic system. The concept of semiotic fitting has an early analogue in Jakob von Uexküll’s concept of ‘Einpassung’. The close concepts of ‘semiotic fitness’, introduced by Jesper Hoffmeyer and by Stéphanie Walsh Matthews, ‘semiotic selection’, introduced by Timo Maran and Karel Kleisner, and ‘semiotic niche’, introduced by Hoffmeyer, provide different versions of the same model. If community is constructing itself on the basis of fitting, then nativeness of the community is a product of fitting, not vice versa. Nativeness is a feature that deepens in the course of community succession. The concept of ‘semiotic fitting’ demonstrates the possibility to analyse the role of both indigenous and alien species or other agents in a community on the basis of a single model. (shrink)

A study of what Descartes calls émotions in his Passions of the Soul suggests that, rather than just a theory of passions—as Descartes himself explicitly claims to be proposing—he was in practice putting forward a more comprehensive theory of passions-émotions, a unified theory which would be closer to what today should properly be called Descartes’ theory of emotions. I try here to make explicit the grounds of this unity by showing that émotions both fit within the functional account Descartes (...) attributes to what he calls passions; and complement the intentionality of passions by expanding it to new objects. In order to show this I offer also a tentative distinction, functionally and intentionally, between passions and émotions in general, on one hand, and, on the other, between the two apparent types of émotions Descartes refers to in the treatise—interior or internal [intérieure] and intellectual [intellectuelle] émotions. (shrink)

Individual-as-maximizing agent analogies result in a simple understanding of the functioning of the biological world. Identifying the conditions under which individuals can be regarded as fitness maximizing agents is thus of considerable interest to biologists. Here, we compare different concepts of fitness maximization, and discuss within a single framework the relationship between Hamilton’s (J Theor Biol 7:1–16, 1964) model of social interactions, Grafen’s (J Evol Biol 20:1243–1254, 2007a) formal Darwinism project, and the idea of evolutionary stable strategies. We distinguish cases (...) where phenotypic effects are additive separable or not, the latter not being covered by Grafen’s analysis. In both cases it is possible to define a maximand, in the form of an objective function ϕ(z), whose argument is the phenotype of an individual and whose derivative is proportional to Hamilton’s inclusive fitness effect. However, this maximand can be identified with the expression for fecundity or fitness only in the case of additive separable phenotypic effects, making individual-as-maximizing agent analogies unattractive (although formally correct) under general situations of social interactions. We also feel that there is an inconsistency in Grafen’s characterization of the solution of his maximization program by use of inclusive fitness arguments. His results are in conflict with those on evolutionary stable strategies obtained by applying inclusive fitness theory, and can be repaired only by changing the definition of the problem. (shrink)

Bayesians often assume, suppose, or conjecture that for any reasonable explication of the notion of simplicity a prior can be designed that will enforce a preference for hypotheses simpler in just that sense. Further, it is often claimed that the Bayesian framework automatically implements Occam's razor—that conditionalizing on data consistent with both a simple theory and a complex theory more or less inevitably favours the simpler theory. But it is shown here that there are simplicity-driven approaches to curve-fitting problems that (...) cannot be captured within the orthodox Bayesian framework and that the automatic razor does not function for such problems. (shrink)

The fitness of any evolutionary unit can be understood in terms of its two basic components: fecundity (reproduction) and viability (survival). Trade-offs between these fitness components drive the evolution of life-history traits in extant multicellular organisms. We argue that these trade-offs gain special significance during the transition from unicellular to multicellular life. In particular, the evolution of germ–soma specialization and the emergence of individuality at the cell group (or organism) level are also consequences of trade-offs between the two basic fitness (...) components, or so we argue using a multilevel selection approach. During the origin of multicellularity, we study how the group trade-offs between viability and fecundity are initially determined by the cell level trade-offs, but as the transition proceeds, the fitness trade-offs at the group level depart from those at the cell level. We predict that these trade-offs begin with concave curvature in single-celled organisms but become increasingly convex as group size increases in multicellular organisms. We argue that the increasingly convex curvature of the trade-off function is driven by the cost of reproduction which increases as group size increases. We consider aspects of the biology of the volvocine green algae – which contain both unicellular and multicellular members – to illustrate the principles and conclusions discussed. (shrink)

The etiological approach to ‘proper functions’ in biology can be strengthened by relating it to Robert Cummins' general treatment of function ascription. The proper functions of a biological trait are the functions it is assigned in a Cummins-style functional explanation of the fitness of ancestors. These functions figure in selective explanations of the trait. It is also argued that some recent etiological theories include inaccurate accounts of selective explanation in biology. Finally, a generalization of the notion of selective explanation (...) allows an analysis of the proper functions of human artifacts. (shrink)