Ramsey's device [2], for eliminating theoretical terms from a theory assumes that the theory has only finitely many axioms. Paul Berent [1], has recently suggested a modification of Ramsey's method that is designed to cover the infinite case. But, his modified method is quite unlike Ramsey's in that it involves an ascent from the original theory to a suitable metatheory. Thus, it is perhaps of some interest to note that there is an extension of Ramsey's method that covers the infinite (...) case and at the same time is much closer in spirit to his original suggestion. (shrink)

In his essay "on likeness of meaning" nelson goodman proposed that two terms have the same meaning if and only if they have the same primary and secondary extensions. In a later essay "on some differences about meaning" he reformulates his proposal: two terms have the same meaning if and only if they have the same extension and certain of their parallel compounds have the same extension. First, I argue that because the first but not the second formulation allows for (...) interlinguistic meaning comparisons, Goodman proposed two theories on synonymy rather than one. Second, I argue that the first theory suffers from the fatal defect of entailing that any two coextensive terms are synonymous. (shrink)

This book presents a collection of articles on applied general equilibrium analysis by major contributors to this field. This rapidly expanding method of analysis involves the use of computers to study entire economies and the interrelationships among firms, households and governments in these economies. There are also articles on the particular computational techniques involved in the numerical estimation of these equilibrium models and on several particular applications. Papers deal with the United States, Mexican and Australian economies. Other chapters provide an (...) analysis of long-run energy problems, fiscal federalism and economic planning. (shrink)

Certain sections ofJosiah Willard Gibbs's thermodynamics papers might be applicable to biological equilibrium and growth, normal or abnormal.Gibbs added terms⌆ Μ i dm i to the differential of the internal energy dε=tdη−pdΝ, where μi=δεδmi is the potential of substancem i , to provide for chemical as well as thermal and mechanical equilibrium. In this article a further generalization is suggested, to include biological equilibrium by adding to de terms of the form GdN, the variableN being the number of cells, where (...) G=δεδN is a “growth potential” that measures exactly the resistance toward spontaneous growth. The functionG, likeΜ i is intensive in nature except for a conversion factor dMdN ,M=⌆m i , affording possible insight into why incipient abnormal growth is often independent of the number of cells. Useful applications might follow from identities between δGδη,δGδv , or δGδmi and δtδN,−δpδN or δμiδN respectively. The following new function is studied, ζ¯=ζ−GN , a natural generalization of theGibbs free energy function ζ, the possibility of measuring it electrically, and comparison of its role with that of ζ for the possible experimental determination ofG. Gibbs's necessary and sufficient conditions for heterogeneous equilibrium ofn components inm phases are generalized and also modified to include broader restraining conditions like ∑mi=1δNj⩾o ,j=1,f,n, the > being characteristic of only living cellular phases. Careful appraisal of the term “biological stability” is followed by new criteria for stability, instability, and limits of stability, in terms of derivatives ofG, with possible medical applications. Three different sections of Gibbs's works tend to indicate that, for a biological phase, lower pressure usually increases its stability. The equation p′′−p′=σ , where σ=surface tension,p′, p′ = pressures,r, r′=radii of curvature, is applied to possible control of tissue growth at interfaces. Methods of altering the equilibrum between three phasesA, B, C by varying the interfacial tensionsσ AB ,σ BC ,σ AC , using relations like AB <σ AC + BC for stability of theA, B interface, suggest different means for shifting biological equilibrium between normal and abnormal cells through the introduction of new third phases at the interface. Various devices are mentioned for possible control of growth through proper channeling of surface or other equivalent forms of energy. (shrink)

The present study investigated the influence of emotional stimuli in the flanker task. In six experiments, separate influences of anticipating and reacting to valence-laden stimuli (affective pictures or facial expressions) on the flanker effect and its sequential modulation (also known as conflict adaptation) were examined. The results showed that there was little evidence that emotional stimuli influenced cognitive control when positive and negative stimuli appeared randomly during the flanker task. When positive and negative stimuli were separated between different participant groups (...) in order to exclude a possible contamination from the effect of one valence to that of another, the sequential modulation was reduced when valence-laden stimuli were anticipated or had been presented on a preceding trial, regardless of the valence of the stimuli. A similar pattern was also obtained with facial expressions but only for response accuracy and only after valence-laden stimuli were presented on a preceding trial. The influences of anticipating and reacting to emotional stimuli were only partially replicated in the final two experiments where the arousal and valence of affective pictures were manipulated orthogonally. The lack of consistent influences of emotional stimuli on the flanker effect challenges the existing theories that implicate affective contributions to cognitive control. (shrink)

Purpose: Our aim was to determine if self-determined motivation (SDM) in elite, men’s soccer changes over time and differs as a function of age, skill-grouping, and engagement in soccer play and practice. We tested predictions from the Developmental Model of Sport Participation (DMSP) regarding relations between practice and play and SDM among both elite and non-elite samples. Methods: Elite youth soccer players in the UK (n = 31; from the Under 13/U13 yr and U15 yr age groups) completed practice history (...) and motivation questionnaires at time1 (T1) and ~2 years later (T2: now U15 yr & U17 yr). Non-elite players (n = 32; from U15 yr and U17 yr) completed the same questionnaires at T2 only. Results: For the elite groups, global SDM decreased over time for the current U17 group (from U15), but no change was seen for the current U15 group (from U13). Age group differences at T2 mirrored these data, with U17 players showing lower global SDM and higher controlled motivation than U15 elites. The non-elite players did not show age group differences, but elites scored higher for global SDM and autonomous motivation than non-elites. The recent hours accumulated in practice negatively correlated with global SDM in elite and non-elite groups, but play was unrelated to measures of motivation. Conclusions: Differences in SDM as a function of age and skill point towards the dynamic nature of these motivations over time, likely a result of proximity to external rewards related to professional status. Although high volumes of practice are related to lower global SDM in both skill groups, the absence of any relations between SDM and soccer play does not support a key prediction related to the DMSP. (shrink)