Critical race theorists and standpoint epistemologists argue that agents who are members of dominant social groups are often in a state of ignorance about the extent of their social dominance, where this ignorance is explained by these agents' membership in a socially dominant group (e.g., Mills 2007). To illustrate this claim bluntly, it is argued: 1) that many white men do not know the extent of their social dominance, 2) that they remain ignorant as to the extent of their dominant (...) social position even where this information is freely attainable, and 3) that this ignorance is due in part to the fact that they are white men. We argue that on Buchak's (2010, 2013) model of risk averse instrumental rationality, ignorance of one's privileges can be rational. This argument yields a new account of elite-group ignorance, why it may occur, and how it might be alleviated. (shrink)

Discovering high-level causal relations from low-level data is an important and challenging problem that comes up frequently in the natural and social sciences. In a series of papers, Chalupka etal. (2015, 2016a, 2016b, 2017) develop a procedure forcausal feature learning (CFL) in an effortto automate this task. We argue that CFL does not recommend coarsening in cases where pragmatic considerations rule in favor of it, and recommends coarsening in cases where pragmatic considerations rule against it. We propose a new technique, (...) pragmatic causal feature learning (PCFL), which extends the original CFL algorithm in useful and intuitive ways. We show that PCFL has the same attractive measure-theoretic properties as the original CFL algorithm. We compare the performance of both methods through theoretical analysis and experiments. (shrink)

A given causal system can be represented in a variety of ways. How do agents determine which variables to include in their causal representations, and at what level of granularity? Using techniques from Bayesian networks, information theory, and decision theory, we develop a formal theory according to which causal representations reflect a trade-off between compression and informativeness, where the optimal trade-off depends on the decision-theoretic value of information for a given agent in a given context. This theory predicts that, all (...) else being equal, agents prefer causal models that are as compressed as possible. When compression is associated with information loss, however, all else is not equal, and our theory predicts that agents will favor compressed models only when the information they sacrifice is not informative with respect to the agent’s anticipated decisions. We then show, across six studies reported here (N=2,364) and one study reported in the supplemental materials (N=182), that participants’ preferences over causal models are in keeping with the predictions of our theory. Our theory offers a unification of different dimensions of causal evaluation identified within the philosophy of science (proportionality and stability), and contributes to a more general picture of human cognition according to which the capacity to create compressed (causal) representations plays a central role. (shrink)

Consider the following two (hypothetical) generic causal claims: “Living in a neighborhood with many families with children increases purchases of bicycles” and “living in an affluent neighborhood with many families with children increases purchases of bicycles.” These claims not only differ in what they suggest about how bicycle ownership is distributed across different neighborhoods (i.e., “the data”), but also have the potential to communicate something about the speakers’ values: namely, the prominence they accord to affluence in representing and making decisions (...) about the social world. Here, we examine the relationship between the level of granularity with which a cause is described in a generic causal claim (e.g., neighborhood vs. affluent neighborhood) and the value of the information contained in the causal model that generates that claim. We argue that listeners who know any two of the following can make reliable inferences about the third: 1) the level of granularity at which a speaker makes a generic causal claim, 2) the speaker’s values, and 3) the data available to the speaker. We present results of four experiments (N=1,323) in the domain of social categories that provide evidence in keeping with these predictions. (shrink)

Recent research on the metaethical beliefs of ordinary people appears to show that they are metaethical pluralists that adopt different metaethical standards for different moral judgments. Yet the methods used to evaluate folk metaethical belief rely on the assumption that participants interpret what they are asked in metaethical terms. We argue that most participants do not interpret questions designed to elicit metaethical beliefs in metaethical terms, or at least not in the way researchers intend. As a result, existing methods are (...) not reliable measures of metaethical belief. We end by discussing the implications of our account for the philosophical and practical implications of research on the psychology of metaethics. (shrink)

Discussions concerning whether there is a natural right to health care may occur in various forms, resulting in policy recommendations for how to implement any such right in a given society. But health care policies may be judged by international standards including the UN Universal Declaration of Human Rights. The rights enumerated in the UDHR are grounded in traditions of moral theory, a philosophical analysis of which is necessary in order to adjudicate the value of specific policies designed to enshrine (...) rights such as a right to health care. We begin with an overview of the drafting of the UDHR and highlight the primary influence of natural law theory in validating the rights contained therein. We then provide an explication of natural law theory by reference to the writings of Thomas Aquinas, as well as elucidate the complementary “capabilities approach” of Martha Nussbaum. We conclude that a right to health care ought to be guaranteed by the state. (shrink)

Purpose – The purpose of this paper is to ask whether a first-order-cybernetics concept, Shannon’s Information Theory, actually allows a far-reaching mathematics of perception allegedly derived from it, Norwich et al.’s “Entropy Theory of Perception”. Design/methodology/approach – All of The Entropy Theory, 35 years of publications, was scrutinized for its characterization of what underlies Shannon Information Theory: Shannon’s “general communication system”. There, “events” are passed by a “source” to a “transmitter”, thence through a “noisy channel” to a “receiver”, that passes (...) “outcomes” (received events) to a “destination”. Findings – In the entropy theory, “events” were sometimes interactions with the stimulus, but could be microscopic stimulus conditions. “Outcomes” often went unnamed; sometimes, the stimulus, or the interaction with it, or the resulting sensation, were “outcomes”. A “source” was often implied to be a “transmitter”, which frequently was a primary afferent neuron; elsewhere, the stimulus was the “transmitter” and perhaps also the “source”. “Channel” was rarely named; once, it was the whole eye; once, the incident photons; elsewhere, the primary or secondary afferent. “Receiver” was usually the sensory receptor, but could be an afferent. “Destination” went unmentioned. In sum, the entropy theory’s idea of Shannon’s “general communication system” was entirely ambiguous. Research limitations/implications – The ambiguities indicate that, contrary to claim, the entropy theory cannot be an “information theoretical description of the process of perception”. Originality/value – Scrutiny of the entropy theory’s use of information theory was overdue and reveals incompatibilities that force a reconsideration of information theory’s possible role in perception models. A second-order-cybernetics approach is suggested. (shrink)

Shannon’s information theory has been a popular component of first-order cybernetics. It quantifies information transmitted in terms of the number of times a sent symbol is received as itself, or as another possible symbol. Sent symbols were events and received symbols were outcomes. Garner and Hake reinterpreted Shannon, describing events and outcomes as categories of a stimulus attribute, so as to quantify the information transmitted in the psychologist’s category (or absolute judgment) experiment. There, categories are represented by specific stimuli, and (...) the human subject must assign those stimuli, singly and in random order, to the categories that they represent. Hundreds of computations ensued of information transmitted and its alleged asymptote, the sensory channel capacity. The present paper critically re-examines those estimates. It also reviews estimates of memory capacity from memory experiments. It concludes that absolute judgment is memory-limited and that channel capacities are actually memory capacities. In particular, there are factors that affect absolute judgment that are not explainable within Shannon’s theory, factors such as feedback, practice, motivation, and stimulus range, as well as the anchor effect, sequential dependences, the rise in information transmitted with the increase in number of stimulus dimensions, and the phenomena of masking and stimulus duration dependence. It is recommended that absolute judgments be abandoned, because there are already many direct estimates of memory capacity. (shrink)

This paper analyses the relationship between Public Administration, Knowledge Management and Service Delivery and to understand if improved Knowledge Management in the South African Government can improve public sector service delivery. This paper is a systematic analysis of 150 secondary literature sources. Even though not all the secondary literature sources analysed are used or cited in the paper, they nonetheless contributed to the identification of several key issues. The main finding of this paper is that improved Knowledge Management in the (...) South African Government would ultimately result in improved public sector service delivery. There is a dearth of empirical research on Knowledge Management in the South African Government, including whether the public sector's adoption of private-sector methods to better itself is effective. From a Public Administration standpoint, none of the literature analysed explains how to successfully integrate Knowledge Management in the "South African Government to improve service delivery." More research on this subject is necessary. Especially, to determine the impact of Knowledge Management on investor confidence, and the inflow of Foreign Direct Investment. The research will benefit governments of developing countries, particularly South Africa, Public Administration scholars, and Knowledge Management professionals. (shrink)

This article examines public administration from 1890 to 2023 to see how it evolved and influenced practice and if good governance is a crucial component in this transformation. This paper presents an in-depth review of several different pieces of secondary literature sources. This paper produced several key findings. The most important finding of this literature study is that, between 1890 and 1980, the Public Administration transitioned from "Traditional Public Administration" to "New Public Management" due to the growing need for good (...) governance. The year 2000 saw the birth of a novel idea in public administration known as "New Public Governance," which has persisted in practice ever since. This paper will be useful to Public Administration practitioners worldwide. There has been little empirical research into how the evolution of Public Administration encourages governments to act more like private corporations. Consequently, more research on this subject is encouraged. (shrink)

Although Knowledge Management was introduced as a Key Performance Indicator (KPI) for all senior management in South Africa 15 years ago, its implementation has been slow and inconsistent. This paper aimed to identify the factors that contribute to or deter the implementation of Knowledge Management in the South African government. The issue was explored through a review of literature on Knowledge Management, as well as results of an interview and questionnaire completed by government officials doing Knowledge Management practitioner work in (...) the South African government. The quantitative data was analysed using DATAtab. The findings identified two key factors that deter the implementation of Knowledge Management in the South African government: most departments in the South African government do not value Knowledge Management, and public officials responsible for implementing Knowledge Management in their departments lack implementation skills. A lack of research on Knowledge Management in developmental governments exists. More research on this subject is necessary. The research will benefit Knowledge Management and Public Administration practitioners alike. (shrink)

Information flow in a system is a core cybernetics concept. It has been used frequently in Sensory Psychology since 1951. There, Shannon Information Theory was used to calculate "information transmitted" in "absolute identification" experiments involving human subjects. Originally, in Shannon's "system", any symbol received ("outcome") is among the symbols sent ("events"). Not all symbols are received as transmitted, hence an indirect noise measure is calculated, "information transmitted", which requires knowing the confusion matrix, its columns labeled by "event" and its rows (...) labeled by "outcome". Each matrix entry is dependent upon the frequency with which a particular outcome corresponds to a particular event. However, for the sensory psychologist, stimulus intensities are "events"; the experimenter partitions the intensity continuum into ranges called "stimulus categories" and "response categories", such that each confusion-matrix entry represents the frequency with which a stimulus from a stimulus category falls within a particular response category. Of course, a stimulus evokes a sensation, and the subject's immediate memory of it is compared to the memories of sensations learned during practice, to make a categorization. Categorizing thus introduces "false noise", which is only removed if categorizations can be converted back to their hypothetical evoking stimuli. But sensations and categorizations are both statistically distributed, and the stimulus that corresponds to a given mean categorization cannot be known from only the latter; the relation of intensity to mean sensation, and of mean sensation to mean categorization, are needed. Neither, however, are presently knowable. This is a quandary, which arose because sensory psychologists ignored an ubiquitous component of Shannon's "system", the uninvolved observer, who calculates "information transmitted". Human sensory systems, however, are within de facto observers, making "false noise" inevitable. (shrink)

All contributions included in the present issue were originally prepared for an “Author Meets Critics” session organized by Carl Sachs for the Eastern Division Meeting of the American Philosophical Association in Savannah, Georgia, on 5th January, 2018.

In 1948, Claude Shannon introduced his version of a concept that was core to Norbert Wiener's cybernetics, namely, information theory. Shannon's formalisms include a physical framework, namely a general communication system having six unique elements. Under this framework, Shannon information theory offers two particularly useful statistics, channel capacity and information transmitted. Remarkably, hundreds of neuroscience laboratories subsequently reported such numbers. But how (and why) did neuroscientists adapt a communications-engineering framework? Surprisingly, the literature offers no clear answers. To therefore first answer (...) "how", 115 authoritative peer-reviewed papers, proceedings, books and book chapters were scrutinized for neuroscientists' characterizations of the elements of Shannon's general communication system. Evidently, many neuroscientists attempted no identification of the system's elements. Others identified only a few of Shannon's system's elements. Indeed, the available neuroscience interpretations show a stunning incoherence, both within and across studies. The interpretational gamut implies hundreds, perhaps thousands, of different possible neuronal versions of Shannon's general communication system. The obvious lack of a definitive, credible interpretation makes neuroscience calculations of channel capacity and information transmitted meaningless. To now answer why Shannon's system was ever adapted for neuroscience, three common features of the neuroscience literature were examined: ignorance of the role of the observer, the presumption of "decoding" of neuronal voltage-spike trains, and the pursuit of ingrained analogies such as information, computation, and machine. Each of these factors facilitated a plethora of interpretations of Shannon's system elements. Finally, let us not ignore the impact of these "informational misadventures" on society at large. It is the same impact as scientific fraud. (shrink)

This paper is based on the premise that public officials in developing countries lack the necessary skills to implement Knowledge Management (KM) successfully, so a framework is required to facilitate this process. South Africa is the case study. It is therefore necessary to develop a Knowledge Management Implementation Framework (KMIF). Consequently, one of the objectives of this paper is to validate this need and then outline a KMIF that can help government departments in developing countries implement KM and foster a (...) KM culture. A mixed methodology approach was used, combining qualitative and quantitative data collection. Based on the Taro Yamane formula, 139 people were selected from a target population of 221 officials involved in KM in the South African government. DATAtab, a web-based statistics application, was used to analyze the responses. A comprehensive review of several secondary literature sources was carried out. For the literature review, relevant peer-reviewed articles were downloaded from Google Scholar, ResearchGate, Scopus, and Phil Papers. The study posits that officials charged with KM implementation in the South African government lack the necessary implementation skillset, that a need for a KMIF exists, and subsequently outlines a three-stage KMIF to facilitate their efforts. This study recommends that the proposed three-stage KMIF be adopted since it will provide the government (i) a simplified and structured way of realizing KM; (ii) it will be an effective tool that officials can use to guide them on how to implement KM, and (iii) it will cultivate a KM culture within the government. Even though the study is original to the South African government, the findings, however, may be applied to other emerging governments in Africa and beyond. Despite its theoretical nature, the paper lacks empirical validation, leaving it open to further investigation. (shrink)

AI is increasingly becoming based upon Internet-dependent systems to handle the massive amounts of data it requires to function effectively regardless of the availability of stable Internet connectivity in every affected community. As such, sustainable development (SD) for rural and mountain communities will require more than just equitable access to broadband Internet connection. It must also include a thorough means whereby to ensure that affected communities gain the education and tools necessary to engage inclusively with new technological advances, whether they (...) be focused on machine learning algorithms or community infrastructure, as they will be increasingly dependent upon the automational capabilities of AI. In this essay, an exploration will be conducted into the means whereby student-engaged learning (SEL) can effectively be utilized to provide targeted, inclusive education to rural and mountain communities regarding the implications of AI for SD. (shrink)

Modus ponens is the argument from premises of the form If A, then B and A to the conclusion B. Nearly all participants agree that the modus ponens conclusion logically follows when the argument appears in this Basic form. However, adding a further premise can lower participants’ rate of agreement—an effect called suppression. We propose a theory of suppression that draws on contemporary ideas about conditional sentences in linguistics and philosophy. Semantically, the theory assumes that people interpret an indicative conditional (...) as a context-sensitive strict conditional: true if and only if its consequent is true in each of a contextually determined set of situations in which its antecedent is true. Pragmatically, the theory claims that context changes in response to new assertions, including new conditional premises. Thus, the conclusion of a modus ponens argument may no longer be accepted in the changed context. Psychologically, the theory describes people as capable of reasoning about broad classes of possible situations, ordered by typicality, without having to reason about individual possible worlds. The theory accounts for the main suppression phenomena, and it generates some novel predictions that new experiments confirm. (shrink)

In general, visual experiences represent determinately. And visual experiences, generally, represent properties of distal objects like their colour, shape, and size, but they do not, generally, represent properties of proximal states like that of incoming light or the retina. By making perceptual constancies central to perceptual representation, Peter Schulte extends Karen Neander’s Causal-Informational Teleosemantic theory in order to accommodate these facts. However, by appealing to the psychophysics and chemistry of how light-related properties interact to produce stimulation to the visual system (...) and how the visual system processes such input to produce experiences, I argue that Schulte’s theory fails to accommodate the facts of distality and determinacy. (shrink)

Purpose – In the last half-century, individual sensory neurons have been bestowed with characteristics of the whole human being, such as behavior and its oft-presumed precursor, consciousness. This anthropomorphization is pervasive in the literature. It is also absurd, given what we know about neurons, and it needs to be abolished. This study aims to first understand how it happened, and hence why it persists. Design/methodology/approach – The peer-reviewed sensory-neurophysiology literature extends to hundreds (perhaps thousands) of papers. Here, more than 90 (...) mainstream papers were scrutinized. Findings – Anthropomorphization arose because single neurons were cast as “observers” who “identify”, “categorize”, “recognize”, “distinguish” or “discriminate” the stimuli, using math-based algorithms that reduce (“decode”) the stimulus-evoked spike trains to the particular stimuli inferred to elicit them. Without “decoding”, there is supposedly no perception. However, “decoding” is both unnecessary and unconfirmed. The neuronal “observer” in fact consists of the laboratory staff and the greater society that supports them. In anthropomorphization, the neuron becomes the collective. Research limitations/implications – Anthropomorphization underlies the widespread application to neurons Information Theory and Signal Detection Theory, making both approaches incorrect. Practical implications – A great deal of time, money and effort has been wasted on anthropomorphic Reductionist approaches to understanding perception and consciousness. Those resources should be diverted into more-fruitful approaches. Originality/value – A long-overdue scrutiny of sensory-neuroscience literature reveals that anthropomorphization, a form of Reductionism that involves the presumption of single-neuron consciousness, has run amok in neuroscience. Consciousness is more likely to be an emergent property of the brain. (shrink)

Purpose – The purpose of this paper is to examine the popular “information transmitted” interpretation of absolute judgments, and to provide an alternative interpretation if one is needed. Design/methodology/approach – The psychologists Garner and Hake and their successors used Shannon’s Information Theory to quantify information transmitted in absolute judgments of sensory stimuli. Here, information theory is briefly reviewed, followed by a description of the absolute judgment experiment, and its information theory analysis. Empirical channel capacities are scrutinized. A remarkable coincidence, the (...) similarity of maximum information transmitted to human memory capacity, is described. Over 60 representative psychology papers on “information transmitted” are inspected for evidence of memory involvement in absolute judgment. Finally, memory is conceptually integrated into absolute judgment through a novel qualitative model that correctly predicts how judgments change with increase in the number of judged stimuli. Findings – Garner and Hake gave conflicting accounts of how absolute judgments represent information transmission. Further, “channel capacity” is an illusion caused by sampling bias and wishful thinking; information transmitted actually peaks and then declines, the peak coinciding with memory capacity. Absolute judgments themselves have numerous idiosyncracies that are incompatible with a Shannon general communication system but which clearly imply memory dependence. Research limitations/implications – Memory capacity limits the correctness of absolute judgments. Memory capacity is already well measured by other means, making redundant the informational analysis of absolute judgments. Originality/value – This paper presents a long-overdue comprehensive critical review of the established interpretation of absolute judgments in terms of “information transmitted”. An inevitable conclusion is reached: that published measurements of information transmitted actually measure memory capacity. A new, qualitative model is offered for the role of memory in absolute judgments. The model is well supported by recently revealed empirical properties of absolute judgments. (shrink)

Purpose – A key cybernetics concept, information transmitted in a system, was quantified by Shannon. It quickly gained prominence, inspiring a version by Harvard psychologists Garner and Hake for “absolute identification” experiments. There, human subjects “categorize” sensory stimuli, affording “information transmitted” in perception. The Garner-Hake formulation has been in continuous use for 62 years, exerting enormous influence. But some experienced theorists and reviewers have criticized it as uninformative. They could not explain why, and were ignored. Here, the “why” is answered. (...) The paper aims to discuss these issues. Design/methodology/approach – A key Shannon data-organizing tool is the confusion matrix. Its columns and rows are, respectively, labeled by “symbol sent” (event) and “symbol received” (outcome), such that matrix entries represent how often outcomes actually corresponded to events. Garner and Hake made their own version of the matrix, which deserves scrutiny, and is minutely examined here. Findings – The Garner-Hake confusion-matrix columns represent “stimulus categories”, ranges of some physical stimulus attribute (usually intensity), and its rows represent “response categories” of the subject’s identification of the attribute. The matrix entries thus show how often an identification empirically corresponds to an intensity, such that “outcomes” and “events” differ in kind (unlike Shannon’s). Obtaining a true “information transmitted” therefore requires stimulus categorizations to be converted to hypothetical evoking stimuli, achievable (in principle) by relating categorization to sensation to intensity. But those relations are actually unknown, perhaps unknowable. Originality/value – The author achieves an important understanding: why “absolute identification” experiments do not illuminate sensory processes. (shrink)

Purpose – For half a century, neuroscientists have used Shannon Information Theory to calculate “information transmitted,” a hypothetical measure of how well neurons “discriminate” amongst stimuli. Neuroscientists’ computations, however, fail to meet even the technical requirements for credibility. Ultimately, the reasons must be conceptual. That conclusion is confirmed here, with crucial implications for neuroscience. The paper aims to discuss these issues. Design/methodology/approach – Shannon Information Theory depends upon a physical model, Shannon’s “general communication system.” Neuroscientists’ interpretation of that model is (...) scrutinized here. Findings – In Shannon’s system, a recipient receives a message composed of symbols. The symbols received, the symbols sent, and their hypothetical occurrence probabilities altogether allow calculation of “information transmitted.” Significantly, Shannon’s system’s “reception” (decoding) side physically mirrors its “transmission” (encoding) side. However, neurons lack the “reception” side; neuroscientists nonetheless insisted that decoding must happen. They turned to Homunculus, an internal humanoid who infers stimuli from neuronal firing. However, Homunculus must contain a Homunculus, and so on ad infinitum – unless it is super-human. But any need for Homunculi, as in “theories of consciousness,” is obviated if consciousness proves to be “emergent.” Research limitations/implications – Neuroscientists’ “information transmitted” indicates, at best, how well neuroscientists themselves can use neuronal firing to discriminate amongst the stimuli given to the research animal. Originality/value – A long-overdue examination unmasks a hidden element in neuroscientists’ use of Shannon Information Theory, namely, Homunculus. Almost 50 years’ worth of computations are recognized as irrelevant, mandating fresh approaches to understanding “discriminability.”. (shrink)

Introduction & Objectives: Norwich’s Entropy Theory of Perception (1975 [1] -present) stands alone. It explains many firing-rate behaviors and psychophysical laws from bare theory. To do so, it demands a unique sort of interaction between receptor and brain, one that Norwich never substantiated. Can it now be confirmed, given the accumulation of empirical sensory neuroscience? Background: Norwich conjoined sensation and a mathematical model of communication, Shannon’s Information Theory, as follows: “In the entropic view of sensation, magnitude of sensation is regarded (...) as a measure of the entropy or uncertainty of the stimulus signal” [2]. “To be uncertain about the outcome of an event, one must first be aware of a set of alternative outcomes” [3]. “The entropy-establishing process begins with the generation of a [internal] sensory signal by the stimulus generator. This is followed by receipt of the [external] stimulus by the sensory receptor, transmission of action potentials by the sensory neurons, and finally recapture of the [response to the internal] signal by the generator” [4]. The latter “recapture” differentiates external from internal stimuli. The hypothetical “stimulus generators” are internal emitters, that generate photons in vision, audible sounds in audition (to Norwich, the spontaneous otoacoustic emissions [SOAEs]), “temperatures in excess of local skin temperature” in skin temperature sensation [4], etc. Method (1): Several decades of empirical sensory physiology literature was scrutinized for internal “stimulus generators”. Results (1): Spontaneous photopigment isomerization (“dark light”) does not involve visible light. SOAEs are electromechanical basilar-membrane artefacts that rarely produce audible tones. The skin’s temperature sensors do not raise skin temperature, etc. Method (2): The putative action of the brain-and-sensory-receptor loop was carefully reexamined. Results (2): The sensory receptor allegedly “perceives”, experiences “awareness”, possesses “memory”, and has a “mind”. But those traits describe the whole human. The receptor, thus anthropomorphized, must therefore contain its own perceptual loop, containing a receptor, containing a perceptual loop, etc. Summary & Conclusions: The Entropy Theory demands sensory awareness of alternatives, through an imagined brain-and-sensory-receptor loop containing internal “stimulus generators”. But (1) no internal “stimulus generators” seem to exist and (2) the loop would be the outermost of an infinite nesting of identical loops. (shrink)

The object of research: The study revolves around KM and service delivery. It ascertains whether KM is a plausible solution to public service delivery challenges. Although the paper is aimed at governments worldwide, it is focusing on South Africa. Investigated problem: While the public service in South Africa has been significantly transformed since apartheid’s end in 1994, the government is now under enormous pressure to deliver and save the public service from further collapse. Recent years have seen an increase in (...) service delivery demonstrations and marches. Many believe the public service delivery mechanisms introduced to circumvent public service delivery challenges have been ineffective. The main scientific results: Despite knowing what must be done, officials have trouble putting their plans, strategies, and policies into action. This is even though service delivery mechanisms were implemented to help them improve service delivery. In fact, only half of the respondents (50.7 %, n=33) were aware of service delivery mechanisms, though 95.4 % (n=62) concurred that KM is a viable solution to improve service delivery. Area of practical use of the research results: Very little research has been conducted on KM as a potential solution to South Africa’s service delivery problems. As a result, this research provides new insights into improving public sector service delivery using KM. Overall, the findings will benefit KM and Public Administration practitioners. (shrink)

Purpose – This study aims to examine the observer’s role in “infant psychophysics”. Infant psychophysics was developed because the diagnosis of perceptual deficits should be done as early in a patient’s life as possible, to provide efficacious treatment and thereby reduce potential long-term costs. Infants, however, cannot report their perceptions. Hence, the intensity of a stimulus at which the infant can detect it, the “threshold”, must be inferred from the infant’s behavior, as judged by observers (watchers). But whose abilities are (...) actually being inferred? The answer affects all behavior-based conclusions about infants’ perceptions, including the well-proselytized notion that auditory stimulus-detection thresholds improve rapidly during infancy. Design/methodology/approach – In total, 55 years of infant psychophysics is scrutinized, starting with seminal studies in infant vision, followed by the studies that they inspired in infant hearing. Findings – The inferred stimulus-detection thresholds are those of the infant-plus-watcher and, more broadly, the entire laboratory. The thresholds are therefore tenuous, because infants’ actions may differ with stimulus intensity; expressiveness may differ between infants; different watchers may judge infants differently; etc. Particularly, the watcher’s ability to “read” the infant may improve with the infant’s age, confounding any interpretation of perceptual maturation. Further, the infant’s gaze duration, an assumed cue to stimulus detection, may lengthen or shorten nonlinearly with infant age. Research limitations/implications – Infant psychophysics investigators have neglected the role of the observer, resulting in an accumulation of data that requires substantial re-interpretation. Altogether, infant psychophysics has proven far too resilient for its own good. Originality/value – Infant psychophysics is examined for the first time through second-order cybernetics. The approach reveals serious unresolved issues. (shrink)

A ‘Black Box’ cannot be opened to reveal its mechanism. Rather, its operations are inferred through input from (and output to) an ‘observer’. All of us are observers, who attempt to understand the Black Boxes that are Minds. The Black Box and its observer constitute a system, differing from either component alone: a ‘greater’ Black Box to any further-external-observer. To Glanville (1982), the further-external-observer probes the greater-Black-Box by interacting directly with its core Black Box, ignoring that Box’s immediate observer. In (...) later accounts, however, Glanville’s greater-Black-Box inexplicably becomes unitary. Why the discrepancy? To resolve it, we start with von Foerster’s archetype ‘machines’, that are of two kinds: ‘Trivial’ (predictable) and ‘Non-Trivial’ (non-predictable). Early-on, Glanville treated the core Black Box and its observer as Trivial Machines, that gradually ‘whiten’ (reveal) each other though input and output, becoming ‘white boxes’. Later, however, Black Box and observer became Non-Trivial Machines, never fully ‘whitenable’. But Non-Trivial Machines can be concatenated from Trivial Machines, and are the only true Black Boxes; any greater-Black-Box (Non-Trivial Machine) may (within its core Black Box) involve white boxes (that are Trivial Machines). White boxes, therefore, could be the ultimate source of the greatest Black Box of all: the Mind. (shrink)

In 1947, Hardy, Wolff, and Goodell achieved a psychophysics milestone: they built a putative sensation-growth scale, for skin pain, from pain-difference limens. Limens were found using the “dolorimeter”, a device first made by Hardy & co. to evoke pain for pain-threshold measurements. Scant years later, though, H.K. Beecher (MD) discredited the pain scale – according to Paterson (2019), citing the historian Tousignant. Yet Hardy & co. receive approval in the literature. Intrigued, we scrutinized their methods, then Beecher’s critiques, and Tousignant’s (...) history of threshold dolorimetry. Beecher decried dolorimetry as irrelevant, favoring clinical trials of pain relief. But he failed to discredit dolorimetry. (shrink)

An ongoing mystery in sensory science is how sensation magnitude F(I), such as loudness, increases with increasing stimulus intensity I. No credible, direct experimental measures exist. Nonetheless, F(I) can be inferred algebraically. Differences in sensation have empirical (but non-quantifiable) minimum sizes called just-noticeable sensation differences, ∆F, which correspond to empirically-measurable just-noticeable intensity differences, ∆I. The ∆Is presumably cumulate from an empirical stimulus-detection threshold I_th up to the intensity of interest, I. Likewise, corresponding ∆Fs cumulate from the sensation at the stimulus-detection (...) threshold, F(I_th ), up to F(I). Regarding the ∆Is, however, it is unlikely that all of them will be known experimentally; the procedures are too lengthy. The customary approach, then, is to find ∆I at a few widely-spaced intensities, and then use those ∆Is to interpolate all ∆Is using some smooth continuous function. The most popular of those functions is Weber’s Law, ∆I⁄I=K. But that is often not even a credible approximation to the data. However, there are other equations for ∆I⁄I. Any such equation for ∆I⁄I can be combined with any equation for ∆F, through calculus, to altogether obtain F(I). Here, two assumptions for ∆F are considered: ∆F=B (Fechner’s Law) and (∆F⁄F)=g (Ekman’s Law). The respective integrals involve lower bounds I_th and F(I_th ). This stands in broad contrast to the literature, which heavily favors non-bounded integrals. We, hence, obtain 24 new, alternative equations for sensation magnitude F(I) (12 equations for (∆I⁄I) × 2 equations for ∆F). (shrink)

This paper concerns the Black Box. It is not the engineer’s black box that can be opened to reveal its mechanism, but rather one whose operations are inferred through input from (and output to) a companion observer. We are observers ourselves, and we attempt to understand minds through interactions with their host organisms. To this end, Ranulph Glanville followed W. Ross Ashby in elaborating the Black Box. The Black Box and its observer together form a system having different properties than (...) either component alone, making it a greater Black Box to any further-external observer. How far into this greater box can a further-external observer probe? The answer is crucial to understanding Black Boxes, and so an answer is offered here. It employs von Foerster’s machines, abstract entities having mechano-electrical bases, just like putative Black Boxes. Von Foerster follows Turing, Ashby, E. F. Moore, and G. H. Mealy in recognizing archetype machines that he calls trivial (predictable) and non-trivial (non-predictable). It is argued here that non-trivial machines are the only true Black Boxes. But non-trivial machines can be concatenated from trivial machines. Hence, the utter core of any greater Black Box (a non-trivial machine) may involve two (or more) White Boxes (trivial machines). This is how an unpredictable thing emerges from predictable parts. Interactions of White Boxes—of trivial machines—may be the ultimate source of the mind. Keywords: . (shrink)

A major question in sensory science is how a sensation of magnitude F (such as loudness) depends upon a sensory stimulus of physical intensity I (such as a sound-pressure-wave of root-mean-square sound-pressure-level). An empirical just-noticeable sensation difference (∆F)_j at F_j specifies a just-noticeable intensity difference (∆I)_j at I_j. Classically, intensity differences accumulate from a stimulus-detection threshold I_th up to a desired intensity I. The corresponding sensation differences likewise accumulate up to F(I) from F(I_th ), the non-zero sensation (as suggested by (...) hearing studies) at I_th. Consequently, sensation growth F(I) can be obtained through classic Fechnerian integration, in which some empirically-based relation for the Weber Fraction, ∆I⁄I, is combined with either Fechner’s Law ∆F=B or Ekman’s Law (∆F⁄F)=g. The number of steps in I is equated to the number of steps in F; an infinite series ensues, whose higher-order terms are traditionally ignored (Fechnerian integration). But also, remarkably, so are the integration bounds I_th and F(I_th ). Here, we depart from orthodoxy by including those bounds. Bounded Fechnerian integration is first used to derive hypothetical sensation-growth equations for which the differential ∆F(I)=F(I+∆I)-F(I) does indeed return either Fechner’s Law or Ekman’s Law respectively. One relation emerges: linear growth of sensation F with intensity I. Subsequently, 24 sensation-growth equations F(I) that the author had derived using bounded Fechnerian integration (12 equations for the Weber Fraction (∆I⁄I), each combined with either Fechner’s Law or with Ekman’s Law) are scrutinized for whether their differentials F(I+∆I)-F(I) return the respective Fechner’s Law or Ekman’s Law, particularly in the previously-unexamined limits (∆I⁄I)≪1 and (∆I⁄I)→0. Classic claims made by Luce and Edwards (1958) are then examined, viz., that three popular forms of the Weber Fraction, when combined with Fechner’s Law, produce sensation-magnitude equations that subsequently return the selfsame Fechner’s Law. When sensation-growth equations are derived here using bounded Fechnerian integration, Luce and Edwards (1958) prove to be wrong. (shrink)

There has been a call for a potentially revolutionary change to our existing understanding of the psychological concept of personal identity. Apparently, people can psychologically represent people, including themselves, as multiple individuals at the same time. Here we ask whether the intransitive judgments found in these studies truly reflect the operation of an intransitive concept of personal identity. We manipulate several factors that arbitrate between transitivity and intransitivity and find most support for transitivity: in contrast to prior work, most participants (...) do not make intransitive judgments when there is any reason to favor one individual over another. People change which single individual they personally identify with, depending on which individual competes more strongly or weakly for identity, rather than identifying with both individuals. Even when two individuals are identical and therefore both entitled to be the same person, we find that people make more transitive judgments once they understand the practical commitments of their responses (Experiment 4), and report not being able to actually imagine two perspectives simultaneously when reasoning about the scenario (Experiment 5). In short, we suggest that while people may make intransitive judgments, these do not reflect that they psychologically represent identity in an intransitive manner. (shrink)

When central authority fails in socially crucial tasks, mutual aid, solidarity, and grassroots organization frequently arise as people take up slack on the basis of informal networks and civil society organizations. We can learn something important about the possibility of horizontal organization by studying such experiments. In this paper we focus on the rationality, care, and effectiveness of grassroots measures to respond to the pandemic and show how they illustrate core elements of anarchist thought. We do not argue for the (...) correctness of any version of anarchist politics, nor claim that the bulk of this grassroots work was done with anarchist ideas explicitly in mind. Nonetheless, the current pandemic, like many social crises before it, serves as a sort experiment in political implementation. -/- Two things have been striking in the US response to the COVID-19 pandemic: the chaos, incompetence, irrationality, and often cruel misguidedness of the centralized government response; and the rationality, care, and effectiveness of grassroots measures in many parts of the country. In this paper we focus on the latter—especially the case of Washington, DC—to illustrate core features of anarchist politics. We do not argue for the correctness of any version of anarchist politics here, but merely illustrate guiding ideas that have been a part of anarchist theory and practice for well over a century. We also do not claim that the bulk of this grassroots work was done with anarchist ideas in mind, or explicitly out of a commitment to anarchist politics. Some was, and some arises out of related ideological commitments, but most simply functions out of no more than a desire to support one another. -/- The current pandemic, like many social crises before it, rather than providing a stand-alone argument or functioning as an implementation of any political theory, serves as a sort of laboratory experiment. When central authority fails in socially crucial tasks, mutual aid, solidarity, and grassroots organization frequently arise as people take up slack on the basis of informal networks and civil society organizations. We can learn something important about the possibility of horizontal organization by studying such experiments, including how it arises through spontaneous action. If political thought is best illustrated through its implementation in practice, the functioning of grassroots individuals and organizations in a time of crisis is one way to understand the political mechanisms core to anarchist thought. (shrink)

Purpose – Neuroscientists act as proxies for implied anthropomorphic signal- processing beings within the brain, Homunculi. The latter examine the arriving neuronal spike-trains to infer internal and external states. But a Homunculus needs a brain of its own, to coordinate its capabilities – a brain that necessarily contains a Homunculus and so on indefinitely. Such infinity is impossible – and in well-cited papers, Attneave and later Dennett claim to eliminate it. How do their approaches differ and do they (in fact) (...) obviate the Homunculi? Design/methodology/approach – The Attneave and Dennett approaches are carefully scrutinized. To Attneave, Homunculi are effectively “decision-making” neurons that control behaviors. Attneave presumes that Homunculi, when successively nested, become successively “stupider”, limiting their numbers by diminishing their responsibilities. Dennett likewise postulates neuronal Homunculi that become “stupider” – but brain-wards, where greater sophistication might have been expected. Findings – Attneave’s argument is Reductionist and it simply assumes-away the Homuncular infinity. Dennett’s scheme, which evidently derives from Attneave’s, ultimately involves the same mistakes. Attneave and Dennett fail, because they attempt to reduce intentionality to non-intentionality. Research limitations/implications – Homunculus has been successively recognized over the centuries by philosophers, psychologists and (some) neuroscientists as a crucial conundrum of cognitive science. It still is. Practical implications – Cognitive-science researchers need to recognize that Reductionist explanations of cognition may actually devolve to Homunculi, rather than eliminating them. Originality/value – Two notable Reductionist arguments against the infinity of Homunculi are proven wrong. In their place, a non-Reductionist treatment of the mind, “Emergence”, is discussed as a means of rendering Homunculi irrelevant. (shrink)

In Cybernetics (1961 Edition), Professor Norbert Wiener noted that “The role of information and the technique of measuring and transmitting information constitute a whole discipline for the engineer, for the neuroscientist, for the psychologist, and for the sociologist”. Sociology aside, the neuroscientists and the psychologists inferred “information transmitted” using the discrete summations from Shannon Information Theory. The present author has since scrutinized the psychologists’ approach in depth, and found it wrong. The neuroscientists’ approach is highly related, but remains unexamined. Neuroscientists (...) quantified “the ability of [physiological sensory] receptors (or other signal-processing elements) to transmit information about stimulus parameters”. Such parameters could vary along a single continuum (e.g., intensity), or along multiple dimensions that altogether provide a Gestalt – such as a face. Here, unprecedented scrutiny is given to how 23 neuroscience papers computed “information transmitted” in terms of stimulus parameters and the evoked neuronal spikes. The computations relied upon Shannon’s “confusion matrix”, which quantifies the fidelity of a “general communication system”. Shannon’s matrix is square, with the same labels for columns and for rows. Nonetheless, neuroscientists labelled the columns by “stimulus category” and the rows by “spike-count category”. The resulting “information transmitted” is spurious, unless the evoked spike-counts are worked backwards to infer the hypothetical evoking stimuli. The latter task is probabilistic and, regardless, requires that the confusion matrix be square. Was it? For these 23 significant papers, the answer is No. (shrink)

This paper reveals errors within Norwich et al.’s Entropy Theory of Perception, errors that have broad implications for our understanding of perception. What Norwich and coauthors dubbed their “informational theory of neural coding” is based on cybernetics, that is, control and communication in man and machine. The Entropy Theory uses information theory to interpret human performance in absolute judgments. There, the continuum of the intensity of a sensory stimulus is cut into categories and the subject is shown exemplar stimuli of (...) each category. The subject must then identify individual exemplars by category. The identifications are recorded in the Garner-Hake version of the Shannon “confusion matrix”. The matrix yields “H”, the entropy (degree of uncertainty) about what stimulus was presented. Hypothetically, uncertainty drops as a stimulus lengthens, i.e. a plot of H vs. stimulus duration should fall monotonically. Such “adaptation” is known for both sensation and firing rate. Hence, because “the physiological adaptation curve has the same general shape as the psychophysical adaptation curve”, Norwich et al. assumed that both have the same time course; sensation and firing rate were thus both declared proportional to H. However, a closer look reveals insurmountable contradictions. First, the peripheral neuron hypothetically cannot fire in response to a stimulus of a given intensity until after somehow computing H from its responses to stimuli of various intensities. Thus no sensation occurs until firing rate adapts, i.e. attains its spontaneous rate. But hypothetically, once adaptation is complete, certainty is reached and perception ends. Altogether, then, perception cannot occur until perception is over. Secondly, sensations, firing rates, and H’s are empirically not synchronous, contrary to assumption. In sum, the core concept of the cybernetics-based Entropy Theory of Perception, that is, that uncertainty reduction is the basis for perception, is irrational. (shrink)

When product design teams gather at the whiteboard in big-tech office parks and startup garages around the world, they ask themselves: How will customers use our technology? Is it better than our competitors’? How much money can we make? But one question that’s rarely asked: does our technology advance human flourishing? -/- In a new white paper by Harvard professor Danielle Allen and her colleagues Eli Frankel, Woojin Lim, Divya Siddarth, Josh Simons, and Glen Weyl entitled “The Ethics of Decentralized (...) Social Technologies: Lessons from Web3, the Fediverse, and Beyond,” the authors not only ask this question but offer a powerful framework for answering it. Drawing on the accumulated wisdom of democratic societies, the authors show that the values of democratic governance that have promoted human flourishing can be translated into a rubric for judging new technologies. -/- In this short research brief, we unpack and comment on the four-step logic at the core of their case. Ultimately, their argument demonstrates the power and the challenge – and above all, the urgency – of placing human flourishing at the center of technology governance. (shrink)

Conditional perfection is the phenomenon in which conditionals are strengthened to biconditionals. In some contexts, “If A, B” is understood as if it meant “A if and only if B.” We present and discuss a series of experiments designed to test one of the most promising pragmatic accounts of conditional perfection. This is the idea that conditional perfection is a form of exhaustification—that is a strengthening to an exhaustive reading, triggered by a question that the conditional answers. If a speaker (...) is asked how B comes about, then the answer “If A, B” is interpreted exhaustively to meaning that A is the only way to bring about B. Hence, “A if and only if B.” We uncover evidence that conditional perfection is a form of exhaustification, but not that it is triggered by a relationship to a salient question. (shrink)

Nineteen Prescott Fire Department, Granite Mountain Hot Shot (GMHS) wildland firefighters and supervisors (WFF), perished on the June 2013 Yarnell Hill Fire (YHF) in Arizona. The firefighters left their Safety Zone during forecast, outflow winds, triggering explosive fire behavior in drought-stressed chaparral. Why would an experienced WFF Crew, leave ‘good black’ and travel downslope through a brush-filled chimney, contrary to their training and experience? An organized Serious Accident Investigation Team (SAIT) found, “… no indication of negligence, reckless actions, or violations (...) of policy or protocol.” Despite this, many WFF professionals deemed the catastrophe, “… the final, fatal link, in a long chain of bad decisions with good outcomes.” This paper is a theoretical and realistic examination of plausible, faulty, human decisions with prior good outcomes; internal and external impacts, influencing the GMHS; and two explanations for this catastrophe: Individual Blame Logic and Organizational Function Logic, and proposed preventive mitigations. (shrink)

Nineteen Prescott Fire Department, Granite Mountain Hot Shot (GMHS) wildland firefighters (WF) perished in Arizona in June 2013 Yarnell Hill Fire, an inexplicable wildland fire disaster. In complex wildland fires, sudden, dynamic changes in human factors and fire conditions can occur, thus mistakes can be unfortunately fatal. Individual and organizational faults regarding the predictable, puzzling, human failures that will result in future WF deaths are addressed. The GMHS were individually, then collectively fixated with abandoning their Safety Zone to reengage, committing (...) themselves at the worst possible time, to relocate to another Safety Zone - a form of collective tunnel vision. Our goal is to provoke meaningful discussion toward improved wildland firefighter safety with practical solutions derived from a long-established wildland firefighter expertise/performance in a fatality-prone profession. Wildfire fatalities are unavoidable, hence these proposals, applied to ongoing training, can significantly contribute to other well-thought-out and validated measures to reduce them. (shrink)

This paper aims to provide a roadmap to AI governance. In contrast to the reigning paradigms, we argue that AI governance should not be merely a reactive, punitive, status-quo-defending enterprise, but rather the expression of an expansive, proactive vision for technology—to advance human flourishing. Advancing human flourishing in turn requires democratic/political stability and economic empowerment. Our overarching point is that answering questions of how we should govern this emerging technology is a chance not merely to categorize and manage narrow risk (...) but also to construe the risks and opportunities much more broadly, and to make correspondingly large investments in public goods, personnel, and democracy itself. To lay out this vision, we take four steps. First, we define some central concepts in the field, disambiguating between forms of technological harms and risks. Second, we review normative frameworks governing emerging technology that are currently in use around the globe. Third, we outline an alternative normative framework based in power-sharing liberalism. Fourth, we walk through a series of governance tasks that ought to be accomplished by any policy framework guided by our model of power-sharing liberalism. We follow these with proposals for implementation vehicles. (shrink)

Readers assume that commonplace properties of the real world also hold in realistic fiction. They believe, for example, that the usual physical laws continue to apply. But controversy exists in theories of fiction about whether real individuals exist in the story’s world. Does Queen Victoria exist in the world of Jane Eyre, even though Victoria is not mentioned in it? The experiments we report here find that when participants are prompted to consider the world of a fictional individual (“Consider the (...) world of Jane Eyre…”), they are willing to say that a real individual (e.g., Queen Victoria) can exist in the same world. But when participants are prompted to consider the world of a real individual, they are less willing to say that a fictional individual can exist in that world. The asymmetry occurs when we ask participants both if a real person is in the character’s world and if the person would appear there. However, the effect is subject to spatial and temporal constraints. When the person and the character share spatial and temporal settings, interchange is more likely to occur. These results shed light on the author’s implicit contract with the reader, which can license the reader to augment a fictional world with features that the author only implicates as part of the work’s background. (shrink)

Cyclist Lance Armstrong cheated his way to seven Tour de France . Such cheating is wrong because it harms society. To explain how that harm affects all of us, I use Aristotle's ideas of virtue ethics to argue that Armstrong, despite his charitable work, is not a virtuous person. Virtue is to some extent determined by society, so we need to be clear that Armstrong is not a person to emulate. A society which does not clearly disapprove of vice (...) is less than it might otherwise be because a good society is one that encourages virtue in its citizens. (shrink)

Reasoning es una obra monumental de más de mil páginas editada en estrecha colaboración por el filósofo Jonathan E. Adler y el psicólogo Lance J. Rips para esclarecer el intrincado campo de investigación relacionado con los fundamentos de la inferencia y, en general, del razonamiento humano. En la actualidad, en pocos casos va unido el trabajo de compilar y editar textos científicos con el afán enciclopédico: un proyecto editorial que sobrepasa con razón los objetivos de la mayor parte de (...) los libros editados para la recopilación de artículos en torno a un mismo tema de investigación. Reasoning supone un empeño de características enciclopédicas: ha conseguido convertirse en una referencia obligada desde que saliera a la luz en 2008 para ofrecer al lector especialista artículos científicos de las más reputadas y consolidadas voces en aquellos campos de conocimiento presentes ya en los proyectos enciclopédicos europeos del siglo de las luces, a saber: el significado del racionalismo, los límites imputables a la naturaleza del conocimiento humano, las paradojas presentes en la inducción, etc. (shrink)

There has been a movement aiming to teach agents about their privilege by making the information about their privilege as costless as possible. However, some argue that in risk-sensitive frameworks, such as Lara Buchak’s (2013), it can be rational for privileged agents to shield themselves from learning about their privilege, even if the information is costless and relevant. This threatens the efficacy of these information-access efforts in alleviating the problem of elite-group ignorance. In response, I show that even within the (...) same framework, in this case David Kinney and Liam Kofi Bright’s (2021), the rationality of this information avoidance rests on shaky ground in practice. In this framework, whether an agent should avoid information depends on the precise details of (1) how relevant they expect the information to be, (2) their priors about the value of various options, and (3) their risk attitudes. The model suggests that the rationality of elite-group ignorance is a function of structural factors that are pervasive but nonetheless not insurmountable, thus offering a way out of pessimism about elite group education. (shrink)

This paper attempts to explain what a protest is by using the resources of speech-act theory. First, we distinguish the object, redress, and means of a protest. This provided a way to think of atomic acts of protest as having dual communicative aspects, viz., a negative evaluation of the object and a connected prescription of redress. Second, we use Austin’s notion of a felicity condition to further characterize the dual communicative aspects of protest. This allows us to distinguish protest from (...) some other speech acts which also involve a negative evaluation of some object and a connected prescription of redress. Finally, we turn to Kukla and Lance’s idea of a normative functionalist analysis of speech acts to advance the view that protests are a complex speech act constituted by dual input normative statuses and dual output normative statuses. (shrink)

MANEJO NA AVICULTURA: POSTURA, ILUMINAÇÃO E INCUBAÇÃO DOS OVOS -/- MANAGEMENT IN POULTRY: POSTURE, ILUMINATION AND INCUBATION OF THE EGGS -/- 1. INTRODUÇÃO A produção de ovos no Brasil está próxima de 45 bilhões de unidades por ano, mantendo um desenvolvimento constante em todos os seus aspectos: genética, instalações, patologia, alimentação, etc. Ao longo do presente trabalho, pretende-se estabelecer os conceitos que estão ligados à produção de ovos, distribuição de ovoprodutos e refletir as ideias básicas sobre os programas de iluminação (...) nas galinhas. Num segundo bloco serão analisados aspectos relacionados com a incubação dos ovos, como a higiene e o manejo, o tratamento do ovo e, por último, a caracterização dos fatores envolvidos no processo da incubação. 2. PREPARAÇÃO/POSTURA DOS OVOS A galinha começa a ovulação normalmente a partir das 20-22 semanas de vida, se bem que mediante práticas de manejo (alimentação, programas de luz, etc.) pode-se adiantar ou atrasar o momento do início das primeiras ovulações. A genética tem, logicamente, um papel importante na idade em que se alcança a puberdade das aves. Mencionamos ritmos de postura por ser a oviposição facilmente verificável, já que nem toda ovulação é seguida de oviposição, como nos casos de queda da gema na cavidade intraperitoneal. Aos primeiros sinais de postura de ovos em frangas jovens, frequentemente observam-se certas irregularidades como: a) Postura irregular: longos intervalos entre dois ovos ou mais de um ovo por dia (geralmente são anormais). b) Ovos com casca mole («soft shelled eggs»), sem a adequada classificação de cálcio. c) Ovos com duas gemas. Talvez estes fenômenos sejam provenientes de uma excessiva estimulação do ovário e disfunções do oviduto. Em suma, tudo isto pode ser consequência da falta de sincronização dos complexos mecanismos que regulam o processo. Uma vez regularizada a postura dos ovos, verifica-se que a galinha coloca um número de ovos sucessivos, seguido de uma pausa ou descanso na postura (choco) de um ou vários dias. O número de ovos que põe seguidos é chamado de sequência ou série de postura. Normalmente, essa “pausa” acontece após uma sequência de quatro a seis ovos postos. A sequência de postura de uma galinha pode ser regular, ou seja, que se repete sucessivamente o número de ovos postos de forma contínua, ou irregular quando essa sequência não obedece ao padrão normal, sendo ela derivada. O mesmo aconteceria com os dias de descanso. Como exemplo podemos encontrar: XXXX - XXXX - série e repouso regular XXX — XX — série e descanso irregular O espaço de tempo entre dois ovos de cada série é um caráter individual. Verificações de Menher (1969) indicam que o intervalo médio entre dois ovos sucessivos de uma série depende da duração desta. Em grandes séries diminui o tempo entre dois ovos sucessivos. À medida que a idade da galinha aumenta, as séries diminuem. Também observa-se que o tempo transcorrido entre dois ovos sucessivos é menor na metade da série e máximo no final da série. Uma galinha com uma série regular do tipo: XXXX - XXXX durante um período de tempo concreto permite-nos estabelecer que tem uma intensidade de postura de 80%. A intensidade de postura é definida como a porcentagem de ovos de um efetivo de galinhas num determinado período de tempo. A evolução da porcentagem de postura ao longo da vida produtiva do rebanho nos dá a curva de postura com três fases: crescimento, constância retilínea e decrescente. Define-se como período de postura o intervalo de tempo entre o início da postura da galinha (20-22 semanas) e o fim da mesma. A duração deste período pode ser variável (entre 12 e 20 meses), dependendo de vários fatores. Se observarmos a hora de oviposição dos diferentes ovos de uma série de galinhas, verificaríamos que a mesma se atrasa dia após dia. Este é um fato lógico, tendo em conta que a formação do ovo é superior a 24 horas. Também se comprova que em nenhum caso há oviposições nos períodos de escuridão quando se mantêm programas clássicos de iluminação (porém, é frequente comprovar que uma porcentagem de ovos podem ser postos durante o período de escuridão). O controle dos mecanismos que regulam os ritmos de ovulação e que definirão as séries é muito complexo, então tento fazer um pequeno resumo. Uma vez produzida a ovulação, a presença de um ovo em formação colocaria em funcionamento um sistema «Feedback» negativo da seguinte forma: gema → gera estímulos nervosos → hipotálamo → suprime RH → sem estimulação da hipófise → bloqueio de uma nova ovulação Esta ideia não é tão simples e se desconhecem em profundidade os mecanismos que a regulam. Observe uma figura que detalha melhor a formação do ovo e a passagem pelos respectivos compartimentos reprodutivos da galinha. 3. DISTRIBUIÇÃO DAS OVIPOSIÇÕES Com programas de iluminação clássicos (17L:7N) já assinalámos que a oviposição na galinha realiza-se no período de luz, e que diariamente o momento de tal oviposição irá sendo regredido (atrasado). No entanto, existe algumas horas onde a frequência máxima de postura é concentrada, que normalmente coincide com as 2-4 horas após a iluminação. Se, experimentalmente, fornecermos 24 horas de luz às galinhas, a postura ocorre durante todo o período, seja de forma aleatória ou através os estímulos a determinados pontos de referência de fatores externos periódicos: ruídos, entradas, fala de pessoas, etc., então podemos estabelecer que existe um certo sincronismo. Quando os programas de iluminação que se seguem nas granjas de galinhas poedeiras não se ajustam às 24 horas ou que seguem programas fraccionados, a resposta é diversificada e deixamos sua avaliação até não conhecer os distintos programas especiais de iluminação. 4. BASES DA ILUMINAÇÃO PARA GALINHAS POEDEIRAS O estabelecimento de programas de iluminação começa na fase de recria da franga e dada a influência que a luz exerce sobre o desenvolvimento da maturidade sexual, os programas que se instauram terão um impacto sobre o futuro produtivo das frangas. As considerações que devem ser levadas em conta no estabelecimento dos programas de iluminação são as seguintes: a) Os programas devem ser considerados como uma "globalidade" durante toda a vida da galinha. A instauração de programas de iluminação das galinhas poedeiras deve estar em conformidade com o programa seguido durante a fase de recria. b) Os aumentos no fotoperíodo durante a fase de recria implica um adiantamento no aparecimento da maturidade sexual da galinha. Este efeito deve ser considerado prejudicial, uma vez que esta postura precoce é acompanhada de tamanhos inferiores de ovos (cuja avaliação no mercado é reduzida). Este avanço no início da postura pode levar a uma falta de harmonia entre puberdade e o desenvolvimento corporal (aponta-se para uma maior incidência de prolapsos). Também indica-se que uma maturidade sexual precoce pode ser acompanhada de irregularidades na postura, pior qualidade da casca e até a um maior índice de mortalidade. c) A redução do fotoperíodo durante a recria permite atrasar o momento do início da postura e a produção de ovos é de uma maior dimensão inicial, o que compensa a ligeira diminuição do número de ovos na sua vida produtiva. d) Estabelecido um programa e posto em prática não pode alterar-se o mesmo. e) Nunca diminuir o fotoperíodo na fase de produção de ovos. f) As alterações do fotoperíodo (aumentos ou diminuições) não passam de um conceito de sensibilidade ao fato do que da magnitude dessas alterações. g) As alterações no fotoperíodo afetam inicialmente o consumo de ração das frangas, mas estas adaptam-se rapidamente aos seus níveis de ingestão e suprimento de exigências ao novo fotoperíodo. h) Ações qualitativas (limitação de um nutriente) ou quantitativas na ração fornecida podem permitir, em si mesmas, o atraso da maturidade sexual das frangas, embora não se apliquem normalmente para este fim. O controle quantitativo do gênero alimentício obedece a estratégias destinadas a obter o peso ideal para uma determinada idade de acordo com as normas fornecidas pelo fornecedor das diferentes estirpes comerciais. i) Na decisão final, ao se definir um programa deve-se ter presente: Tipo de alojamento: — Galpão com ambiente controlado. — Galpão convencionais com janelas. Neste último caso a época de nascimento das frangas será um fator relevante a ser levado em consideração. Como aspectos a destacar poderíamos citar: — Durante os primeiros dias de vida da galinha convém fornecer-lhe luz durante as 24 horas, a fim de facilitar a adaptação ao seu novo habitat (localização de comedouros e bebedouros, etc.). — Durante a fase de recria devem ser evitadas falhas que estabeleçam períodos fotocrescentes, já que alterarão a resposta produtiva posterior de tais frangas (especialmente se altera-se na última fase do período decrescente). 4.1 Programas práticos de iluminação na recria Ao longo do trabalho consideraremos sempre uma recria de 20 semanas, embora este dado possa ser variável de acordo com: a) Melhoria genética das estirpes atuais, as quais tendem a ser mais precoces. b) Tentativa de uma maior produção de ovos. No caso de reprodutoras semipesadas, a duração do período de recria pode ser de 21-22 semanas. 4.1.1 Galpões convencionais com janelas Neste tipo de galpão a iluminação externa incide no interior do navio e devem ser estabelecidos programas para combater o aumento de luz natural que se apresenta de janeiro a junho. 1. Programa de fotoperíodo decrescente Para realizar este tipo de programa pode-se seguir esta rotina: a) Verificar na tabela as horas de luz natural (x) que vão dispor-se quando as frangas cumprirem as 20 semanas de vida. b) Aumentar em 6 horas o valor observado na tabela (x + 6 horas) e fornecê-las aos 4 ou 5 dias de vida. c) Diminuir semanalmente a iluminação artificial, de tal forma que quando chegarem às 20 semanas de vida, a luz fornecida coincida com a luz solar. Exemplo prático: frangas nascidas em 8 de janeiro: a) Observa-se em tabela que cumprirão as 20 semanas em 28 de maio, tendo um comprimento do dia de 14 horas e 45 minutos. b) aumentamos em 6 horas e fornecemos 20 horas e 45 minutos a partir do quarto dia. c) Diminuímos semanalmente 360 minutos/20 semanas = 18 minutos e quando cumprirem as 20 semanas de vida, o fotoperíodo de que dispõem (14 horas e 45 minutos) coincide com o comprimento do dia. 2. Programa de fotoperíodo constante a) Para levar a cabo este tipo de programa deve-se verificar na tabela o comprimento do dia mais longo durante as 20 semanas que dura a recria. b) Proporcionar essas horas de luz a partir dos primeiros 3-4 dias durante as 20 semanas. O uso de programas de luz constante em galpões convencionais com janelas não é muito frequente, apesar da certa poupança energética que acarreta. 4.1.2 Galpões com ambiente controlado Neste tipo de galpão considera-se que a luz solar não exerce nenhuma ação no interior do mesmo. No entanto, é necessário atentar-se para que o conceito de galpão totalmente escuro seja levado até às suas últimas consequências, evitando que por sistemas de ventilação, etc., possam existir fugas de luz que alterariam os programas de iluminação propostos. Nos galpões com ambiente controlado seguem-se dois tipos de programas: 1. Programa decrescente-constante Durante as primeiras semanas vai-se diminuindo o fotoperíodo paulatinamente (1 ou 2 horas) até chegar a 8 ou 10 horas, que ficariam constantes até as 20 semanas de idade. Uma variável deste programa consiste em ir diminuindo lentamente as horas de luz e por volta da 12ª semana fazer uma diminuição brusca, deixando um fotoperíodo de 7-8 horas, que se perduraria até às 20 semanas de vida. 2. Programa constante Consiste em proporcionar de 7 a 10 horas de luz constante durante toda a fase de recria (com exceção dos primeiros dias, os quais se consideram de adaptação). Na hora de estabelecer a intensidade luminosa nesta fase de recria nos encontramos com intervalos muito amplos. Diferentes fornecedores de frangas recomendam de 20 a 40 lux durante os primeiros dias e ir diminuindo de tal forma que ao primeiro mês de vida estejam a 10-20 lux. A partir da 5 semana e até 3-4 meses vem sendo recomendada 5-10 lux para que possa, assim, aumentar a intensidade a partir dessa data para níveis de 10-30 lux. 4.2 Programas clássicos de iluminação na fase de postura Uma vez que as frangas tenham atingido as 20 semanas de idade, é preciso estabelecer os programas de iluminação para o período de postura. É necessário considerar, como se fazia no período de recria, o tipo de galpão em que vão residir durante todo o período de postura, bem como o programa seguido na fase de recria. Recordando novamente que ao longo do período de postura nunca se deve diminuir a duração do fotoperíodo, passamos a definir os programas de iluminação mais usuais em função do tipo de galpão: 4.2.1 Galpões convencionais com janelas 1. Programa crescente Consiste em ir incrementando o fotoperíodo a partir da 20ª semana. Podem existir várias opções: a) Aumento do fotoperíodo semanal de forma constante até atingir as 16-17 horas de iluminação. b) Aumento brusco do fotoperíodo às 21 e 23 semanas até atingir as 15,5 horas de iluminação, que ficariam fixas em toda a fase de postura. Esta é uma recomendação clássica de algumas casas comerciais. Em galpões convencionais com janelas, os programas de iluminação constante não costumam ser utilizados. 4.2.2 Galpões de ambiente controlado Neste tipo de galpão deve ser instaurado um programa de fotoperíodo crescente. Às 20 semanas e em função do fotoperíodo que seguiram na fase de recria o incremento pode ser brusco (caso de frangas recriadas com 8-10 horas de iluminação, pode-se passar a 12-13 horas) e seguir posteriormente com incrementos de 20-30 minutos até atingir as 16-17 horas de iluminação. A intensidade da luz durante a fase de produção de ovos é unânime em considerar os valores de 10-15 lux como os mais adequados, desde que exista homogeneidade na sua distribuição. Atualmente, as recomendações das diferentes casas comerciais de estirpes de poedeiras são mais elevadas: na ordem de 20 a 30 lux. Níveis muito superiores não têm efeito sobre a produção de ovos e podem desencadear problemas de arranque de penas quando a intensidade é excessiva. 4.3 Outros programas de iluminação Em instalações de ambiente controlado os custos energéticos representam um capítulo importante dentro dos custos de uma exploração avícola. A fim de economizar energia, uma série de programas de iluminação vem sendo ensaiada, especialmente para a fase de postura, que poderíamos englobar em dois grupos: a) intermitentes ou fracionados. b) Não ajustados a 24 horas. 5. HIGIENE E MANEJO DA INCUBAÇÃO A higiene de todo o processo de incubação deve servir para estabelecer uma primeira medida de ruptura da cadeia de infecção. Há uma série de doenças como Marek, pulorose, encefalomielite aviária, micoplasmose, etc., que estão associadas ao processo de incubação. A higiene de todo o processo deve corresponder inicialmente ao controle na exploração, de tal forma que os reprodutores devem estar, do ponto de vista sanitário, em perfeitas condições e estendê-las ao manejo mecânico do ovo, regulação de entradas e saídas e igualmente a todas as instalações. Antes de continuar com o manejo do ovo para a incubadora, convém recordar alguns aspectos do desenvolvimento embrionário que ocorre dentro da própria galinha: o ovo é fertilizado na parte distal do infundíbulo cerca de 15 minutos após a ovulação, e quando se encontra no istmo (às 5 horas) já se produzem as primeiras divisões celulares. Às 9 horas da ovulação, o blastodermo cresce até um estágio de 256 células e antes da oviposição a formação do tubo digestivo (gastrulação) já está completada no embrião (PARKHURST e MOUNTNEY, 2012). As divisões celulares continuam após a oviposição, desde que as temperaturas estejam acima de 26,8ºC (zero fisiológico). 6. MANEJO DO OVO PARA A INCUBAÇÃO A colheita dos ovos nas explorações de reprodução deve ser efetuada com uma certa periodicidade (três a cinco vezes por dia), a fim de evitar problemas de roturas e de ovos sujos. Não devemos esquecer que a colocação em um mesmo ninho de vários ovos originam modificações nas temperaturas dos mesmos (superiores a zero fisiológico), que poderiam estar associadas a um reinício das divisões celulares no embrião. Uma vez recolhidos, os ovos devem ser instalados num armazém que permita manter uma temperatura de 15-18ºC (nunca inferior a 10ºC) e uma umidade de 70-75% para evitar uma perda de peso excessiva. A temperatura de armazenagem dos ovos para incubação pode variar em função do tempo em que permanecerão armazenados, pelo que é conveniente programar temperaturas mais baixas para um período de armazenagem mais longo. Alguns autores estabelecem que os ovos que permanecerem 3 dias na incubadora podem ser programados com temperaturas de 15ºC, enquanto que os que se armazenam por mais de 9 dias a temperatura recomendada é de 12ºC. Os ovos com problemas de casca, tais como calcificações defeituosas, quebra ou fissura, ovos com formas anormais e ovos com casca lisa e bem formada, devem ser eliminados na própria instalação. A uniformidade do tamanho dos ovos é um aspecto a destacar e o intervalo de peso mais adequado é de 55-65 g. Os ovos de maior tamanho sempre apresentam níveis mais elevados de problemas de casca e o período de incubação do mesmo é superior (até mais de 12 horas), por isso não é aconselhável introduzi-los na incubadora, assim como os ovos pequenos e os de gema dupla. Os trabalhos de Ron Jones (1978) evidenciam a importância do tamanho dos ovos ao considerar que as perdas de peso por evaporação são mais rápidas nos ovos de menor peso, e inclusive assinala que os ovos de casca branca são mais porosos, sugerindo sua incubação separada em função do tamanho. A desinfecção dos ovos (fumigação) com uma solução de formalina é prática corrente (45 ml de uma solução de formalina a 40% e 30 g de permanganato de potássio por metro cúbico de espaço ou 10 g/m3 de paraformaldeído aquecido num fumigador eléctrico), segundo as recomendações do Guia Cobb (1991). Um excesso de gás formaldeído pode ser neutralizado através da introdução de amoníaco líquido concentrado, 20 ml/m3. Pode também utilizar-se uma solução de cloro (500 ppm) a 43ºC durante 2 minutos, bem como produtos com amônio quaternário. Quando o tempo de armazenamento dos ovos para incubação é inferior a uma semana, a posição dos ovos para incubação dificilmente influencia a incubabilidade posterior. No entanto, quando o tempo de armazenamento excede 2 semanas, a incubabilidade dos ovos melhora se eles são virados diariamente. Romanoff, em 1960, estabeleceu os valores de incubabilidade dos ovos em função do tempo de armazenagem, verificando-se que, à medida que o período de tempo entre a postura dos ovos e a colocação na incubadora aumenta, os resultados de incubação diminuem, como pode ser observado na tabela 1: Tabela 1: Valores de incubalidade dos ovos em função do tempo de armazenamento -/- Período de armazenamento (dias) Incubalidade (%) 14 80 21 70 28 30 32 < 10 Fonte: ROMANOFF, 1960. Para evitar mudanças bruscas de temperatura (da sala de armazenamento da incubadora), que podem causar transpirações nos ovos, recomenda-se um aumento gradual da temperatura (12 a 18 horas antes de serem introduzidos na incubadora). Os ovos fecundados que são submetidos a longos percursos até chegarem ao incubatório devem ser mantidos no armazém durante 1 ou 2 dias antes de serem colocados nas incubadoras, melhorando assim os resultados de incubação. Através dos poros há uma troca de gases durante o armazenamento. O dióxido de carbono difunde-se no exterior e a sua concentração no ovo diminui rapidamente nas primeiras 12 horas após a postura. Se juntarmos as perdas de vapor de água, descobriremos que o armazenamento tem um impacto negativo nos resultados finais do processo de incubação. Experimentalmente, o tempo de armazenagem dos ovos fertilizados pode ser prolongado através da embalagem hermética em atmosfera de nitrogênio ou de anidrido carbônico, incluindo o revestimento de óleos. Alguns incubatórios testam o revestimento dos ovos com materiais plásticos para evitar tais perdas, todavia não é muito indicado, uma vez que lacra a passagem do oxigênio exterior para o embrião interior. No caso de nos depararmos com ovos sujos, e apesar dos condicionantes sanitários que vão associados, pode-se recorrer à sua limpeza e lavá-lo com água e algum desinfetante. Se a limpeza for excessiva, deve considerar-se a alteração que pode ter sofrido a cutícula da casca, pelo que não se recomenda a raspagem manual ou mecânica da mesma. De acordo com o estabelecido pelo Guia Cobb (1991), os efeitos mais importantes do armazenamento dos ovos são: a) O armazenamento prolonga o tempo de incubação e, em média, um dia de armazenamento prolonga o tempo de incubação por 1 hora. b) A armazenagem reduz a incubabilidade dos ovos. Este efeito, descrito acima, é quantificado de forma que a partir do quinto dia de armazenamento, cada dia de armazenamento adicional representa perdas de 0,5 a 1% na incubabilidade. c) O peso dos ovos pode diminuir quando o armazenamento dos ovos é de 14 dias ou mais. 6.1 Carregamento dos ovos na incubadora Embora ainda existam incubatórios que introduzem os ovos diretamente do armazém para a incubadora, recomenda-se um pré-aquecimento suave dos ovos até atingir temperaturas próximas dos 23ºC em 6 horas, independentemente da temperatura de partida. Duas horas antes de serem colocados na incubadora, a temperatura considerada ideal é de 28ºC. 6.2 Tempo de incubação Como já foi explicado acima, o tempo necessário para a incubação dos ovos de galinha deriva de uma função de vários fatores, de modo que os 21 dias e 4 horas (508 horas) que são definidos como tempo de referência podem ser ligeiramente modificados. 7. FATORES ENVOLVIDOS NO PROCESSO DE INCUBAÇÃO Os resultados obtidos por diferentes incubatórios variam consideravelmente de um para outros. As causas destas variações podem estar relacionadas ao manejo dos reprodutores, fertilidade dos ovos e na própria incubação. Cada empresa que dispõe de incubatórios desenvolve seu próprio método de operação no processo de incubação e seus padrões de qualidade exigidos nos pintainhos são geralmente variáveis. Vários fatores que desempenham um papel importante no processo de incubação já foram descritos ao comentar o manejo do ovo para incubação: uniformidade de pesos, qualidade de casca, armazenamento, etc., por isso é necessário assinalar os parâmetros a controlar na incubadora e no nascedouro. Em suma, podem ser estabelecidas as seguintes condições: Parâmetros Incubadora Nascedouro Temperatura (ºC) 37,5 – 37,7 37,1 Umidade relativa (%) 55 – 60 < 75 Ventilação (m3/minuto/1000 ovos) 0,14 0,23 – 0,28 Nível de CO2 0,3 – 0,4 0,5 – 0,6 Nível de O2 21 21 Número de viagens/dia < 4 – 6 — Tabela 2: Condições aceitas para a incubação dos ovos e nascimento dos pintainhos. 7.1 Manejo com os pintainhos de 1 dia – do incubatório para os galpões Numa sala convenientemente climatizada, 22-25 ºC e 70-80% de umidade, procedem-se as seguintes operações: a) Triagem dos pintainhos - Eliminando os que apresentem anomalias ou tenham pouca viabilidade/vitalidade, problemas nos membros, bico, olhos, se apresentam-se fracos, etc. b) Sexagem dos pintainhos - A separação dos sexos tem um interesse relativo no caso dos criadouros e criadores, mas é uma operação obrigatória quando o que interessa é produzir galinhas de postura ou reprodutores. Para o processo de separação por sexo podem ser utilizados dois sistemas: — Exame da cloaca, seguindo o método de Masui e Hashimoto, no qual é preciso evaginar a cloaca, mediante pressão, e através de uma luz direta observar as protuberâncias que correspondem a cada sexo. A aplicação desta técnica requer um elevado grau de especialização e os erros daí resultantes são insignificantes. Como regra a seguir, quando se aplica esta técnica, é que sua realização deve estar o mais próximo possível ao momento do nascimento. — Mediante o exame de caracteres ligados ao sexo, os caracteres usados para a determinação do sexo nas aves são vários: cores da plumagem (prateados frente a dourados: lisos frente a barrados), mas o mais empregado na atualidade faz referência à comparação dos comprimentos das penas primárias frente às de cobertura (quando as penas primárias são mais longas que as de cobertura, é uma fêmea). Esta técnica também é realizada dentro de poucas horas de nascimento. c) Vacinação dos pintainhos - Durante as primeiras horas de vida, as aves são normalmente alimentadas por via oral (spray) ou por injeção (com vacina manual ou automática). Vacina-se, também, contra várias doenças no primeiro dia de vida dos pintainhos, como a Marek, Gumboro e Bouba Aviária. d) Embalagem - Desenvolvidas as anteriores operações e já dentro da zona de expedição, realiza-se a última triagem e classificação (no caso dos reprodutores e das frangas, o processo pode ter conotações comerciais e podem apresentar-se no mercado várias classes em função da qualidade do produto, que, neste caso, é normalmente o peso), para posteriormente, contar e introduzi-las nas embalagens correspondentes, que podem ser retornáveis ou não. Nas embalagens normalmente introduz-se uma centena de aves (2 por 100) sem custo como regra de compensação às baixas iniciais. Em todas estas operações, o controle da temperatura e da humidade deve ser rigoroso, tal como descrito acima. e) Transporte - Os veículos de transporte devem estar equipados com sistemas auxiliares de calor e arrefecimento que permitam garantir condições estabelecidas, independentemente da situação atmosférica externa. A temperatura do ar fornecido no transporte deve ser de 28ºC quando as frangas estão em embalagens de plástico, enquanto que se forem de papelão a temperatura requerida pode ser bastante inferior (20ºC), segundo o Guia Cobb (1991). A distribuição da carga no transporte (para que a distribuição térmica seja homogénea), o controle contínuo das condições ambientais e os cuidados na condução e na descarga da mercadoria são os últimos aspectos importantes a assinalar. 8. RESUMO E PRIMEIRAS CONCLUSÕES No presente trabalho, tentou-se expor de forma sucinta os aspectos relacionados com a postura dos ovos: irregularidades no início da postura, sequência de postura, intensidade de postura, curva de postura, período de postura e distribuição de oviposições. O controle da iluminação, com seus diferentes programas, tanto em recria como em postura, é objeto de especial desenvolvimento. Uma terceira parte trata da questão da incubação artificial, começando pela higiene e manejo da incubação. É feita especial referência ao manejo dos ovos a serem incubados, e se resume os fatores que controlam o processo de incubação. -/- Emanuel Isaque Cordeiro da Silva – Departamento de Zootecnia da UFRPE. Recife, 2020. -/- REFERÊNCIAS BIBLIOGRÁFICAS -/- ABAD, M. et al. Reproducción e incubación en avicultura. Real Escuela de Avicultura. España, 2003. CAMPOS, Egladson João. Avicultura: razões, fatos e divergências. São Paulo: FEP-MVZ, 2000. COBB. Manual de manejo de frangos Cobb 500: guia de manejo. São Paulo: Cobb-Vantress Brasil, 2001 CONTO, L. A. Avicultura de postura. Avicultura Industrial, v. 1121, n. 95, 2004. ENSMINGER, M. Eugene. Zootecnia general. Buenos Aires: Centro Regional de Ayuda Técnica, 1973. ESTEBAN, José María Lasheras; ROCHA, Luís Oliveira. Manual de avicultura. Lisboa: Litexa, 1951. LANA, Geraldo Roberto Quintão. Avicultura. Recife: Livraria e Editora Rural Ltda, 2000. LOPES, Jackeline Cristina Ost. Caderno Didático de Avicultura (UFRN/UFPI). Cadernos Pronatec Goiás, v. 1, n. 1, p. 74-173, 2018. MENHER, A. La gallina. Zaragoza: Acribia, 1969. MACARI, Marcos. Manejo da incubação. Campinas: Facta, 2003. MALAQUIAS, Jessica Dantas. Manejo de galinhas poedeiras. 2019. Trabalho de Conclusão de Curso. Graduação em Zootecnia, UFRPE. 42f. Brasil. MALAVAZZI, Gilberto. Avicultura: manual prático. São Paulo: NBL Editora, 1983. PARKHURST, Carmen; MOUNTNEY, George J. Poultry meat and egg production. Berlim: Springer Science & Business Media, 2012. ROMANOFF, A.L. The Avian Embryo. New York: The Macmillan Co., 1960. RON JONES. A closer look at incubation. Poultry International. Vol 17. n° 2. ROSE, S. P. et al. Principles of poultry science. Nova Iorque: CAB International, 1997. WHITE, Fred N.; KINNEY, James L. Avian incubation. Science, v. 186, n. 4159, p. 107-115, 1974. (shrink)

Whether or not deflationism is compatible with truth-conditional theories of meaning has often been discussed in very broad terms. This paper only focuses on Davidsonian semantics and Brandom's anaphoric deflationism and defends the claim that these are perfectly compatible. Critics of this view have voiced several objections, the most prominent of which claims that it involves an unacceptable form of circularity. The paper discusses how this general objection applies to the case of anaphoric deflationism and Davidsonian semantics and evaluates different (...) ways of responding to it (Williams 1999, Horisk 2008 and Lance 1997). Then, three further objections to the compatibility of these theories are assessed and eventually dismissed (Horisk 2007, Patterson 2005 and Collins 2002). It is shown how these considerations shed light on core issues of the debate. (shrink)

Élie HALÉVY (1870-1937), philosophe et historien des idées, fut professeur à l'École libre des sciences politiques, l'ancêtre de l'actuel Sciences Po. Comme son autre grand ouvrage, l'Histoire du peuple anglais au XIXe siècle, paru en six tomes de 1913 à 1932, les trois tomes de La formation du radicalisme philosophique, parus en 1901 pour les deux premiers et en 1904 pour le troisième, reflètent pour partie ses enseignements de l'Ecole libre consacrés à l'histoire britannique. Le premier tome, La jeunesse de (...) Bentham 1776-1789, étudie la doctrine utilitariste non seulement chez celui qu'on regarde comme son fondateur principal, Jeremy Bentham, mais aussi chez les nombreux auteurs qui, en Grande-Bretagne et sur le continent, en dessinèrent avant lui les contours. Le deuxième tome, L’évolution de la doctrine utilitaire de 1789 à 1815, montre comment l'utilitarisme revêtit la forme non seulement d'une école de pensée, mais aussi d'un mouvement pour la réforme économique, sociale et politique. Le rôle coordonnateur nouveau de James Mill, ainsi qu'une convergence de vues avec les économistes, qui poussaient dans le sens des réformes, marquèrent notamment cette évolution. Le troisième tome, Le radicalisme philosophique, continue d'étudier la transformation de l'école en mouvement après la fin des guerres napoléoniennes, lorsque celle-ci commence à engranger ses premiers grands succès réformistes. Bentham, James Mill et les autres penseurs utilitaires sont alors réunis sous l'appellation de philosophic radicals. Le terme temporel de l'ouvrage est le Reform Act de 1832, première étape vers la modernisation du système électoral, que la propagande de ce groupe ne contribua pas peu à faire aboutir. Quoique l'ouvrage d'Halévy vaille en premier lieu par l'immense savoir qu'il déploie, et le nombre et l'excellence des citations qu'il propose, il comporte aussi des thèses historiques et philosophiques originales. On peut citer parmi les premières la thèse, qui relie les trois tomes, voulant que l'utilitarisme britannique trouve sa forme achevée dans l'intervention sur la société, lorsqu'il se mue en radicalisme philosophique, et parmi les secondes, la thèse, énoncée au début du premier tome, voulant qu'il existe trois modèles dominants de jonction des intérêts individuels (la fusion sympathique, l'identification naturelle et l'identification artificielle). Une autre grande thèse, à la fois historique et philosophique, affirme en substance que l'économie politique classique serait un département spécialisé de la pensée utilitaire. La question de savoir jusqu'à quel point Smith, Ricardo et Malthus ont pu adhérer au "principe d'utilité" de Bentham est toujours débattue. En même temps que les élucidations apportées à ce principe, elle contribue à expliquer l'intérêt que les historiens de la pensée économique continuent de porter à l'ouvrage. L'auteur a participé à la réédition de La formation du radicalisme philosophique en 1995 par les Presses Universitaires de France (P.U.F.), suivant un projet collectif lancé par Monique Canto-Sperber. Dans le présent article, antérieur à cette réédition, l'auteur tentait de résumer brièvement un livre qui demeure irremplaçable en dépit d'une conception et d'un style quelque peu datés. (shrink)

Desde os anos 90, a corporeidade vem ocupando um papel cada vez mais central nas explicações das ciências cognitivas. Com isso, surgiram críticas contundentes, tanto do ponto de vista empírico quanto conceitual, à suposição de que a representação é a marca do mental. Apesar disso, cientistas cognitivos parecem relutar em desfazer- se do vocabulário representacionalista. Este artigo tenta lançar luz sobre a questão do suposto representacionalismo de um dos principais paradigmas das ciências cognitivas, o Processamento Preditivo, revisando argumentos pela interpretação (...) não- representacionalista de alguns de seus pontos, assim resgatando a ideia avançada pelas teorias da cognição corporificada segundo a qual a atividade exploratória de um organismo em seu ambiente não exige a geração de modelos representacionais acerca do ambiente. (shrink)