Grice sobre racionalidade

My main goal in this paper is to argue that the concept of rationality is central in Grice’s philosophy. Grice does not affirm this explicitly, but on several occasions throughout his work he indicates that rationality is a key concept, which enables both conversational practice and the development of philosophical theses. In order to show the importance of rationality to Grice, I will analyze his work according to three aspects: (i) logical and teleological; (ii) ethical and metaethical; and (iii) linguistic and pragmatic. In my view, in all three rationality is fundamental. Actually, a proper characterization of some of his philosophical discussions is only possible through this concept. Furthermore, I intend to show the relationships between rationality and other basic concepts in Grice.Keywords: Grice, rationality, values, pragmatics, constructivism.Meu objetivo principal neste artigo é argumentar que o conceito de racionalidade é central na filosofia de Grice. Grice não afirma isto explicitamente, mas, em várias ocasiões ao longo de sua obra, ele indica que racionalidade é um conceito chave, o qual possibilita tanto a prática conversacional, quanto o desenvolvimento de teses filosóficas. Com o intuito de mostrar a importância da racionalidade para Grice, irei analisar sua obra em três aspectos: (i) lógico e teleológico; (ii) ético e metaético; e (iii) linguístico e pragmático. Em meu ponto de vista, em todos os aspectos racionalidade é fundamental. Na verdade, uma adequada caracterização de algumas de suas discussões filosóficas somente é possível através desse conceito. Além disso, pretendo mostrar as relações mantidas entre racionalidade e outros conceitos básicos em Grice.Palavras-chave: Grice, racionalidade, valores, pragmática, construtivismo

É possível derivar dever ser de ser?

Este artigo tem como objetivo principal discutir a chamada Lei de Hume e algumas tentativas de derivação de ‘dever ser’ de ‘ser’. A Lei de Hume, como conhecida na tradição, é a tese que sustenta não ser possível inferir quaisquer conclusões práticas (normativas) de premissas puramente teóricas (factuais). Conforme a interpretação standard da Lei de Hume, existe uma barreira inferencial separando fato de valor. Não obstante, vários filósofos, como John Searle e Max Black, apresentaram contraexemplos com intuito de mostrar que essa interpretação é errada e que é possível, em certos contextos, alcançar conclusões práticas de premissas teóricas. Minha proposta central é criticar os principais argumentos de Searle e Black, em especial, procurando mostrar que eles não são suficientes para invalidar a Lei de Hume. Além disso, sugiro que, embora conclusões práticas não possam ser alcançadas a partir de premissas factuais, elas podem ser alcançadas a partir de premissas mistas

Translation of mRNA and synthesis of basic proteins early during rat liver regeneration

The regenerating rat liver, model for rapid, controlled growth in a mammalian system, was used to investigate molecular events occurring during a transition in growth-rate. This investigation focused on mRNA translation during the early phase of liver regeneration following partial hepatectomy. -- The study included examination of: 1) the translation of polysomal (polyribosomal) mRNA; 2) the possible presence of a polysome-associated factor for stimulating or inhibiting initiation frequency or translation rate; and 3) the synthesis of basic proteins (primarily histones and some ribosomal proteins) during the first 10 h of regeneration. Intact polysomes were isolated, an in vitro translation assay for use with rat liver polysomes (instead of purified mRNA) as template was developed, and a criterion for operationally defining basic proteins was determined. Polysome-associated mRNA, isolated by centrifugation through a discontinuous sucrose gradient, was translated in a wheat germ in vitro translation system; and the translation products were fractionated on a carboxymethyl-cellulose column to quantitate basic proteins. -- It was shown that: 1) the A₂₆₀ polysomes/g liver, an estimate of the quantity of mRNA/g liver, is maximal between 7 and 8 h after partial hepatectomy; 2) an active, polysome-associated factor which influences initiation frequency or translation rate is undetectable; and 3) the peak rate of basic protein systhesis does not occur within the first 10 h postoperatively and thus does not coincide with the peak of polysome content. The peak rate of basic protein synthesis appeared to be much less than that reported in uncontrolled, rapidly growing Ehrlich ascites tumor cells. The results are compatible with the findings of others concerning a) DNA transcription; b) mRNA synthesis, transport, and translation; c) ribosomal protein and histone synthesis early during rat liver regeneration; and d) the absence of a detectable, endogenous, initiation frequency or translation rate-stimulating or inhibiting factor. -- A review of the literature on DNA template activity and on ribosomal proteins and histones and their synthesis following partial hepatectomy in the rat is also included

É possível derivar dever ser de ser?

Este artigo tem como objetivo principal discutir a chamada Lei de Hume e algumas tentativas de derivação de ‘dever ser’ de ‘ser’. A Lei de Hume, como conhecida na tradição, é a tese que sustenta não ser possível inferir quaisquer conclusões práticas (normativas) de premissas puramente teóricas (factuais). Conforme a interpretação standard da Lei de Hume, existe uma barreira inferencial separando fato de valor. Não obstante, vários filósofos, como John Searle e Max Black, apresentaram contraexemplos com intuito de mostrar que essa interpretação é errada e que é possível, em certos contextos, alcançar conclusões práticas de premissas teóricas. Minha proposta central é criticar os principais argumentos de Searle e Black, em especial, procurando mostrar que eles não são suficientes para invalidar a Lei de Hume. Além disso, sugiro que, embora conclusões práticas não possam ser alcançadas a partir de premissas factuais, elas podem ser alcançadas a partir de premissas mistas

Effects of Changed Aircraft Noise Exposure on Experiential Qualities of Outdoor Recreational Areas

The literature indicates that sound and visual stimuli interact in the impression of landscapes. This paper examines the relationship between annoyance with sound from aircraft and annoyance with other area problems (e.g., careless bicycle riding, crowding, etc.), and how changes in noise exposure influence the perceived overall recreational quality of outdoor recreational areas. A panel study (telephone interviews) conducted before and after the relocation of Norway’s main airport in 1998 examined effects of decreased or increased noise exposure in nearby recreational areas (n = 591/455). Sound from aircraft annoyed the largest proportion of recreationists, except near the old airport after the change. The decrease in annoyance with sound from aircraft was accompanied by significant decreases in annoyance with most of the other area problems. Near the new airport annoyance with most factors beside sound from aircraft increased slightly, but not significantly. A relationship between aircraft noise annoyance and perceived overall recreational quality of the areas was found

Dialectics and difference: against Harvey's dialectical post-Marxism

David Harvey`s recent book, Justice, nature and the geography of difference (JNGD), engages with a central philosophical debate that continues to dominate human geography: the tension between the radical Marxist project of recent decades and the apparently disempowering relativism and `play of difference' of postmodern thought. In this book, Harvey continues to argue for a revised `post-Marxist' approach in human geography which remains based on Hegelian-Marxian principles of dialectical thought. This article develops a critique of that stance, drawing on the work of Jacques Derrida, Gilles Deleuze and Felix Guattari. I argue that dialectical thinking, as well as Harvey's version of `post-Marxism', has been undermined by the wide-ranging `post-' critique. I suggest that Harvey has failed to appreciate the full force of this critique and the implications it has for `post-Marxist' ontology and epistemology. I argue that `post-Marxism', along with much contemporary human geography, is constrained by an inflexible ontology which excessively prioritizes space in the theory produced, and which implements inflexible concepts. Instead, using the insights of several `post-' writers, I contend there is a need to develop an ontology of `context' leading to the production of `contextual theories'. Such theories utilize flexible concepts in a multilayered understanding of ontology and epistemology. I compare how an approach which produces a `contextual theory' might lead to more politically empowering theory than `post-Marxism' with reference to one of Harvey's case studies in JNGD

ASPECTO NUTRICIONAL DO BIOCARVÃO NA PRODUÇÃO DE MUDAS DE RÚCULAS EM CONDIÇÕES SEMIÁRIDAS

The production of quality arugula seedlings is one of the crucial steps for the success of the crop in the field. Thus, the objective of this work was to determine complementary dosages of biochar that enable better development of arugula seedlings. The experiment was conducted in a greenhouse of the Federal Rural University of Semi-Arid (UFERSA). The experimental design was completely randomized with six treatments (T1 - 0% biochar, T2 - 10% and 90%, T3 - 20% and 80%, T4 - 30% and 70%, T5 - 40% and 60%, T6 - 50% and 50% of biochar and sand, respectively) and ten repetitions. The evaluated characteristics were: Number of leaves per plant; Plant height; Root length; Neck diameter; Fresh and dry seedling mass. Data were subjected to analysis of variance. The response curve adjustment procedure was performed using the R software. The proportion of 50% of the biochar provided the best seedling performance, promoting significant improvements in the evaluated characteristics.A produção de mudas de rúcula com qualidade constitui uma das etapas cruciais para o sucesso da cultura no campo. Com isso, o objetivo deste trabalho foi determinar dosagens complementares de biocarvão que possibilitem melhor desenvolvimento de mudas de rúcula. O experimento foi conduzido em casa de vegetação da Universidade Federal Rural do Semi-Árido (UFERSA). O delineamento experimental utilizado foi o inteiramente casualizado com seis tratamentos (T1 - 0% de biocarvão, T2 - 10% e 90%, T3 - 20% e 80%, T4 - 30% e 70%, T5 - 40% e 60%, T6 - 50% e 50% de biocarvão e areia, respectivamente) e dez repetições. As características avaliadas foram: Número de folhas por planta; Altura de plantas; Comprimento da raíz; Diâmetro do colo; Massa fresca e massa seca de plântulas. Os dados foram submetidos à análise de variância. O procedimento de ajustamento de curvas de resposta foi realizado utilizando-se o software R. A proporção de 50% do biocarvão foi a que propiciou melhor desempenho das mudas, promovendo melhorias significativas nas características avaliadas

Effects of Changed Aircraft Noise Exposure on the Use of Outdoor Recreational Areas

This paper examines behavioural responses to changes in aircraft noise exposure in local outdoor recreational areas near airports. Results from a panel study conducted in conjunction with the relocation of Norway’s main airport in 1998 are presented. One recreational area was studied at each airport site. The samples (n = 1,264/1,370) were telephone interviewed about their use of the area before and after the change. Results indicate that changed aircraft noise exposure may influence individual choices to use local outdoor recreational areas, suggesting that careful considerations are needed in the planning of air routes over local outdoor recreational areas. However, considerable stability in use, and also fluctuations in use unrelated to the changes in noise conditions were found. Future studies of noise impacts should examine a broader set of coping mechanisms, like intra- and temporal displacement. Also, the role of place attachment, and the substitutability of local areas should be studied