A hypothesis about sensorimotor integration (the λ model) is described and applied to movement control and kinesthesia. The central idea is that the nervous system organizes positional frames of reference for the sensorimotor apparatus and produces active movements by shifting the frames in terms of spatial coordinates. Kinematic and electromyographic patterns are not programmed, but emerge from the dynamic interaction among the system s components, including external forces within the designated frame of reference. Motoneuronal threshold properties and proprioceptive inputs to (...) motoneurons may be cardinal components of the physiological mechanism that produces positional frames of reference. The hypothesis that intentional movements are produced by shifting the frame of reference is extended to multi-muscle and multi-degrees-of-freedom systems with a solution of the redundancy problem that allows the control of a joint alone or in combination with other joints to produce any desired limb configuration and movement trajectory. The model also implies that for each motor behavior, the nervous system uses a strategy that minimizes the number of changeable control variables and keeps the parameters of these changes invariant. Examples are provided of simulated kinematic and electromyographic signals from single- and multi-joint arm movements produced by suggested patterns of control variables. Empirical support is provided and additional tests of the model are suggested. The model is contrasted with others based on the ideas of programming of motoneuronal activity, muscle forces, stiffness, or movement kinematics. (shrink)

All epistemic agents physically consist of parts that must somehow comprise an integrated cognitive self. Biological individuals consist of subunits (organs, cells, molecular networks) that are themselves complex and competent in their own context. How do coherent biological Individuals result from the activity of smaller sub-agents? To understand the evolution and function of metazoan bodies and minds, it is essential to conceptually explore the origin of multicellularity and the scaling of the basal cognition of individual cells into a coherent larger (...) organism. In this paper I synthesize ideas in cognitive science, evolutionary biology, and developmental physiology toward a hypothesis about the origin of Individuality: “Scale-Free Cognition”. I propose a fundamental definition of an Individual based on the ability to pursue goals at an appropriate level of scale and organization, and suggest a formalism for defining and comparing the cognitive capacities of highly diverse types of agents. Any Self is demarcated by a computational surface – the spatio-temporal boundary of events that it can measure, model, and try to affect. This surface sets a functional boundary - a cognitive “light cone” which defines the scale and limits of its cognition. I hypothesize that higher-level goal-directed activity and agency, resulting in larger cognitive boundaries, evolve from the primal homeostatic drive of living things to reduce stress – the difference between current conditions and life-optimal conditions. The mechanisms of developmental bioelectricity - the ability of all cells to form electrical networks that process information - suggests a plausible set of gradual evolutionary steps that naturally lead from physiological homeostasis in single cells to memory, prediction, and ultimately complex cognitive agents, via scale-up of the drive of infotaxis. Recent data on the molecular mechanisms of pre-neural bioelectricity suggest a model of how increasingly sophisticated cognitive functions emerge smoothly from cell-cell communication used to guide embryogenesis and regeneration. This set of hypotheses provides a novel perspective on numerous phenomena, such as cancer, and makes several unique, testable predictions for interdisciplinary research that have implications not only for evolutionary developmental biology but also for biomedicine and perhaps artificial intelligence and exobiology. (shrink)

Reliabilism holds that knowledge is true belief reliably caused. Reliabilists should say something about individuating processes; critics deny that the right degree of generality can be specified without arbitrariness. It is argued that this criticism applies as well to processes mentioned in scientific explanations. The gratuitous puzzles created thereby show that the “generality problem” is illusory.

Meaning has traditionally been regarded as a problem for philosophers and psychologists. Advances in cognitive science since the early 1960s, however, broadened discussions of meaning, or more technically, the semantics of perceptions, representations, and/or actions, into biology and computer science. Here, we review the notion of “meaning” as it applies to living systems, and argue that the question of how living systems create meaning unifies the biological and cognitive sciences across both organizational and temporal scales.

When the history of life on earth is viewed as a history of cell division, all of life becomes a single cell lineage. The growth and differentiation of this lineage in reciprocal interaction with its environment can be viewed as a developmental process; hence the evolution of life on earth can also be seen as the development of life on earth. Here, in reviewing this field, some potentially fruitful research directions suggested by this change in perspective are highlighted. Variation and (...) selection become, for example, bidirectional information flows between scales, while the notions of “cooperation” and “competition” become scale relative. The language of communication, inference, and information processing becomes more useful than the language of causation to describe the interactions of both homogeneous and heterogeneous living systems at any scale. Emerging scale‐free theoretical frameworks such as predictive coding and active inference provide conceptual tools for reconceptualizing biology as the study of a unified, multiscale dynamical system. (shrink)

Large‐scale patterns of correlated growth in development are partially driven by competition for metabolic and informational resources. It is argued that competition between organs for limited resources is an important mesoscale morphogenetic mechanism that produces fitness‐enhancing correlated growth. At the genetic level, the growth of individual characters appears independent, or “modular,” because patterns of expression and transcription are often highly localized, mutations have trait‐specific effects, and gene complexes can be co‐opted as a unit to produce novel traits. However, body parts (...) are known to interact over the course of ontogeny, and these reciprocal exchanges can be an important determinant of developmental outcomes. Genetic mechanisms underlie cell and tissue behaviors that allow organs to communicate with one another, but they also create evolutionarily adaptive competitive dynamics that are driven by physiological and biophysical processes. Advances in the understanding of competitive and closely related coordinative interactions across scales will complement existing research programs that emphasize the role of cellular mechanisms in morphogenesis. Study of the large‐scale order produced by competitive dynamics promises to facilitate advances in basic evolutionary and developmental biology, as well as applied research in fields such as bioengineering and regenerative medicine that aim to regulate patterning outcomes. (shrink)

I argue against the currently popular view that a radical change in theory affects the meaning of theoretical terms, and hence render pre- and post-shift theories incomparable. I first show how to pose the meaning-change issue without appeal to meanings reified. I contend that arguments against theory-neutral observation languages are faulty, but that even if they were sound, there are semantic devices that allow a theory to refer to the factual basis of a competitor. This suggests a picture of science (...) as the accumulation of truths, with each successive stage being more stable. (shrink)

Evolution exploits the physics of non‐neural bioelectricity to implement anatomical homeostasis: a process in which embryonic patterning, remodeling, and regeneration achieve invariant anatomical outcomes despite external interventions. Linear “developmental pathways” are often inadequate explanations for dynamic large‐scale pattern regulation, even when they accurately capture relationships between molecular components. Biophysical and computational aspects of collective cell activity toward a target morphology reveal interesting aspects of causation in biology. This is critical not only for unraveling evolutionary and developmental events, but also for (...) the design of effective strategies for biomedical intervention. Bioelectrical controls of growth and form, including stochastic behavior in such circuits, highlight the need for the formulation of nuanced views of pathways, drivers of system‐level outcomes, and modularity, borrowing from concepts in related disciplines such as cybernetics, control theory, computational neuroscience, and information theory. This approach has numerous practical implications for basic research and for applications in regenerative medicine and synthetic bioengineering. (shrink)

In this paper I respond to Mathias Risse's objections to my critique of his views on racial profiling in Philosophy and Public Affairs. I draw on the work of Richard Sampson and others on racial disadvantage in the USA to show that racial profiling likely aggravates racial injustices that are already there. However, I maintain, clarify and defend my original claim against Risse that racial profiling itself is likely to cause racial injustice, even if we abstract from unfair background conditions. (...) I then respond to Levin's claims that there is no serious racial injustice in the contemporary USA and differentiate between Risse's attempt - albeit unsuccessful - to provide an egalitarian justification for racial profiling from the frankly inegalitarian assumptions that underpin the claims of Michael Levin. (shrink)

I argue that 'c' occurs extensionally in 'c caused e' and 'D' occurs extensionally in 'c caused e because c is D'. I claim that this has been insufficiently appreciated because the two contexts are often run together and because it has not been clear that the description D of c is among the referents of an explanatory argument. I argue as well that Hume's analysis of causation is consistent with taking causation to be a relation between single events, and (...) that even if events are eliminated as virtual entities, extensionality holds for all terms in the resulting context. (shrink)

Examples cited by Feldman, Lehrer and others of true beliefs that are justified, but not by false lemmas, turn out under scrutiny to involve false lemmas after all. In each case there is an EG inference whose conclusion is unwarranted unless its base instance is false. A shift to non-deductive justification does not avert the difficulty. The relation of this result to non-inferential Gettier cases is suggested.

This paper defends the view that homosexuality is abnormal and hence undesirable—not because it is immoral or sinful, or because it weakens society or hampers evolutionary development, but for a purely mechanical reason. It is a misuse of bodily parts. Clear empirical sense attaches to the idea of the use of such bodily parts as genitals, the idea that they are for something, and consequently to the idea of their misuse. I argue on grounds involving natural selection that misuse of (...) bodily parts can with high probability be connected to unhappiness. I regard these matters as prolegomena to such policy issues as the rights of homosexuals, the rights of those desiring not to associate with homosexuals, and legislation concerning homosexuality, issues which I shall not discuss systematically here. However, I do in the last section draw a seemingly evident corollary from my view that homosexuality is abnormal and likely to lead to unhappiness. (shrink)

Significant progress in the molecular investigation of endogenous bioelectric signals during pattern formation in growing tissues has been enabled by recently developed techniques. Ion flows and voltage gradients produced by ion channels and pumps are key regulators of cell proliferation, migration, and differentiation. Now, instructive roles for bioelectrical gradients in embryogenesis, regeneration, and neoplasm are being revealed through the use of fluorescent voltage reporters and functional experiments using well‐characterized channel mutants. Transmembrane voltage gradients (Vmem) determine anatomical polarity and function as (...) master regulators during appendage regeneration and embryonic left‐right patterning. A state‐of‐the‐art recent study reveals that they can also serve as prepatterns for gene expression domains during craniofacial patterning. Continued development of novel tools and better ways to think about physical controls of cell‐cell interactions will lead to mastery of the morphogenetic information stored in physiological networks. This will enable fundamental advances in basic understanding of growth and form, as well as transformative biomedical applications in regenerative medicine. (shrink)

One version of virtue epistemology defines knowledge as belief whose truth arises from, or is explained by, the motives that produced it. This version is also intended to solve the Gettier problem, by shielding properly caused beliefs from double accidents. Unfortunately, there is no notion of "explains" or "arises from" which explains in the intended sense the truth of true beliefs.

Feminism was born in controversy and it continues to flourish in controversy. The distinguished contributors to this volume provide an array of perspectives on issues including: universal values, justice and care, a feminist philosophy of science, and the relationship of biology to social theory.

Birch, Ginsburg, and Jablonka lay out a very convincing case for an important transition marker: unlimited associative learning. Especially welcome are the empirical predictions. I focus here not on the question of how to infer phenomenal consciousness from this behavioral metric, but on possible novel applications of this useful and fundamental framework. Specifically, I highlight two aspects of biology that are often not considered in philosophy of mind approaches that focus on natural species and evolutionary time scales. These are the (...) ability of minds and bodies to change drastically on the time scale of an individual experiencing subject, and bioengineering of novel living forms with no evolutionary history at the organism level. Both of these aspects provide interesting new contexts within which to explore UAL and its implications. (shrink)

This paper is devoted to computer modelling of the development and regeneration of multicellular biological structures. Some species are able to regenerate parts of their body after amputation damage, but the global rules governing cooperative cell behaviour during morphogenesis are not known. Here, we consider a simplified model organism, which consists of tissues formed around special cells that can be interpreted as stem cells. We assume that stem cells communicate with each other by a set of signals, and that the (...) values of these signals depend on the distance between cells. Thus the signal distribution characterizes location of stem cells. If the signal distribution is changed, then the difference between the initial and the current signal distribution affects the behaviour of stem cells—e.g. as a result of an amputation of a part of tissue the signal distribution changes which stimulates stem cells to migrate to new locations, appropriate for regeneration of the proper pattern. Moreover, as stem cells divide and form tissues around them, they control the form and the size of regenerating tissues. This two-level organization of the model organism, with global regulation of stem cells and local regulation of tissues, allows its reproducible development and regeneration. (shrink)

Philosophers have articulated six notions of human freedom. Four are metaphysical. According to one, a man acts freely when he is doing what he wants to ; according to the second, he acts freely when he is not being compelled by outside forces ; according to the third, he acts freely when the prior state of the universe was not a sufficient cause of what he is doing; according to the fourth, he acts freely when he, not any preceding event, (...) is the cause of what he is doing. The third and fourth theories may be called “indeterministic freedom” and “the agency theory,” named only to be rejected. I reject indeterminism out of agreement with a long tradition which holds that there is no reason to think that human actions are ever undetermined, and an undetermined human action would not be “free” in any sense in which we desire our actions to be free and believe that they are in fact free. To appreciate, reflect that agents should control and be accountable for “free” actions. Now, we control an event by assembling or obstructing its sufficient conditions; merefore, an event without sufficient conditions, a random event which just happens, would lie beyond human control and, hence, the sphere of human freedom. Similarly, a man is no more responsible for what happens independently of his choices – and an event without sufficient conditions cannot have a choice as a sufficient condition – than he is responsible for the behavior of a roulette wheel. (shrink)

Putnam argues that, by ‘reinterpretation’, the Axiom of Constructibility can be saved from empirical refutation. This paper contends that this argument fails, a failure which leaves Putnam's sweeping appeal to the Lowenheim –Skolem Theorem inadequately motivated.

It is argued against critics that the concept of race is well-formed. The issue is formulated in terms of the classic sense/reference distinction and shown that "race" has a sense specified in terms of geographic ancestry, and thereby a reference. Excessive constraints on "race," for instance that races must by definition have signature genes, are rejected. Empirical validation is considered, although the emphasis here is to place empirical validation in a philosophical context, not answer the empirical questions themselves. At several (...) junctures the familiar divisions of the races are compared to the stellar luminosity types of astronomy, which are still serviceable although representing an earlier state of astrophysical knowledge. (shrink)

Habituation, a form of non‐associative learning, isno longer studied exclusively within the fields of psychology and neuroscience. Indeed, the same stimulus–response pattern is observed at the molecular, cellular, and organismal scales and is not dependent upon the presence of neurons. Hence, a more inclusive theory is required to accommodate aneural forms of habituation. Here an abstraction of the habituation process that does not rely upon particular biological pathways or substrates is presented. Instead, five generalizable elements that define the habituation process (...) are operationalized. The formulation can be applied to interrogate systems as they respond to several stimulation paradigms, providing new insights and supporting existing behavioral data. The model can be used to deduce the relative contribution of elements that contribute to the measurable output of the system. The results suggest that habituation serves as a general biological strategy that any system can implement to adaptively respond to harmless, repetitive stimuli. (shrink)

The invariant left–right asymmetry of animal body plans raises fascinating questions in cell, developmental, evolutionary, and neuro‐biology. While intermediate mechanisms (e.g., asymmetric gene expression) have been well‐characterized, very early steps remain elusive. Recent studies suggested a candidate for the origins of asymmetry: rotary movement of extracellular morphogens by cilia during gastrulation. This model is intellectually satisfying, because it bootstraps asymmetry from the intrinsic biochemical chirality of cilia. However, conceptual and practical problems remain with this hypothesis, and the genetic data is (...) consistent with a different mechanism. Based on wide‐ranging data on ion fluxes and motor protein action in a number of species, a model is proposed whereby laterality is generated much earlier, by asymmetric transport of ions, which results in pH/voltage gradients across the midline. These asymmetries are in turn generated by a new candidate for “step 1”: asymmetric localization of electrogenic proteins by cytoplasmic motors. BioEssays 25:1002–1010, 2003. © 2003 Wiley Periodicals, Inc. (shrink)

The invariant left–right asymmetry of animal body plans raises fascinating questions in cell, developmental, evolutionary, and neuro‐biology. While intermediate mechanisms (e.g., asymmetric gene expression) have been well‐characterized, very early steps remain elusive. Recent studies suggested a candidate for the origins of asymmetry: rotary movement of extracellular morphogens by cilia during gastrulation. This model is intellectually satisfying, because it bootstraps asymmetry from the intrinsic biochemical chirality of cilia. However, conceptual and practical problems remain with this hypothesis, and the genetic data is (...) consistent with a different mechanism. Based on wide‐ranging data on ion fluxes and motor protein action in a number of species, a model is proposed whereby laterality is generated much earlier, by asymmetric transport of ions, which results in pH/voltage gradients across the midline. These asymmetries are in turn generated by a new candidate for “step 1”: asymmetric localization of electrogenic proteins by cytoplasmic motors. BioEssays 25:1002–1010, 2003. © 2003 Wiley Periodicals, Inc. (shrink)

The Declaration of Helsinki and the Council of the International Organization of Medical Sciences provide guidance on standards of care and prevention in clinical trials. In the current and increasingly challenging research environment, the ethical status of a trial design depends not only on protection of participants, but also on social value, feasibility, and scientific validity. Using the example of a study assessing efficacy of a vaccine to prevent human papilloma virus in HIV-1 infected adolescent girls in low resource countries (...) without access to the vaccine, we compare several trial designs which rank lower on some criteria and higher on others, giving rise to difficult trade-offs. This case demonstrates the need for developing more nuanced guidance documents to help researchers balance these often conflicting criteria. (shrink)

This article considers some recent objections to reliabilism, particularly those of Susan Haack in Evidence and Inquiry. Haack complains that reliabilism solves the “ratification” problem trivially, making it analytic that evidence relates to truth; this paper defends an analytic solution to this problem. It argues as well that reliabilism is not tacitly committed to “evidentialism.” Familiar counterexamples to and repairs of reliabilism are reviewed, with an eye to finding their rationale. Finally, it suggests that the underlying dispute between reliabilism and (...) its critics is the existence of a priori relations between evidence and hypotheses. (shrink)