The aim of this study was to test red - green dichromats' ability to discriminate between illuminant and surface-reflectance changes in natural scenes. Stimuli were simulations of natural scenes presented on a colour monitor with 10-bit resolution per gun. The natural scenes were obtained with a fast hyperspectral imaging system. Six different scenes (including rocks, foliage, and buildings) were tested. In each trial, two images were presented in sequence, each for 1 s, with no interval. The images differed in the (...) phase of daylight on the scene: first with correlated colour temperature 25 000 K, then 6 700 K. The spectral reflectance of a region in the second image was changed randomly, consistent with a local change in daylight. The observer's task was to decide whether a particular surface in the successive images was the same (pure illuminant change) or different (illuminant change with a surface-reflectance change). The performance of four deuteranopes and five protanopes varied considerably across the scenes tested, with mean colour constancy indices (± 1 SEM) of 0.48 (± 0.13) and 0.19 (± 0.10), respectively (1.0 representing ideal performance). Deuteranopes seemed less disadvantaged than protanopes, performing close to normal with some scenes. (shrink)

The number of discriminable colours is often assumed to be of the order of several million but the extent of detectable chromatic diversity present in individual natural scenes is an open question. Here, the aim was to estimate the number of discriminable colours seen in natural scenes. Hyperspectral data were obtained from a set of natural scenes over the range 400 - 720 nm at 10 nm intervals (Nascimento et al, 2002 Journal of the Optical Society of America A 19 (...) 1484 - 1490) and the representation of each scene in CIELAB space computed for all pixels of the image. The number of discriminable colours was estimated by counting the number of unit volumes in the three-dimensional volume defined by the scene when represented in CIELAB space. We found that the number of discriminable colours estimated in a scene could vary by an order of magnitude from scene to scene, but rarely exceeded 105, indicating a limited chromatic diversity. (shrink)

Badawī, ʻAbd al-Raḥmān, 1917-2002; criticism and interpretation.

The purpose of the present study was to address the shortcomings of Cronbach’s alpha concerning the semantic overlap between items. Using an example from a motivational measure, the correction of Cronbach’s alpha was applied by partialing out the effects due to conceptual overlap. The significance of Cronbach’s alpha was tested using simulated random data derived from the measure and by estimating the confidence intervals with known and unknown distributions. The results indicated that the uncorrected conceptual overlap coefficient alpha was equal (...) to 0.89 and 0.66 following the correction. After simulating the corrected statistical results, the distribution of alpha with random numbers had an estimate of 95%, equal to 0.41. The lower bound of the corrected alpha distribution was equal to 0.41, suggesting that the corrected alpha could easily belong to the distribution of alpha developed from simulated random numbers. Thus, the semantic overlap between items on a measure represents a significant threat to the validity of the alpha coefficient. (shrink)

On the life and teachings of Śaṅkarācārya; includes history of Daivadnya Brahmans, Hindu caste in coastal region of Maharashtra, Goa, Karnataka, and Kerala.

Several recent papers dealing with Plato's position on the imperfection of the phenomenal world draw heavily on the differences between two kinds of predicates in order to show the following: In the middle dialogues, Plato posits Forms only as referents of what the writers call incomplete predicates. He does not posit Forms as referents for complete predicates. When interpreters ignore the differences between these kinds of predicates, they ascribe too radical a view regarding the imperfection of the phenomenal world to (...) the middle dialogues. The ontology of these dialogues includes sensible particulars which retain their identity over time even though they are continually changing in some respect or other. (shrink)

John Stuart Mill's Utilitarianism continues to serve as a rich source of moral and theoretical insight. This collection of articles by top scholars offers fresh interpretations of Mill's ideas about happiness, moral obligation, justice, and rights. Applying contemporary philosophical insights, the articles challenge the conventional readings of Mill, and, in the process, contribute to a deeper understanding of utilitarian theory as well as the complexity of moral life.

This book examines Augustine's description of the actually existing world, especially that aspect most important for the human pursuit of happiness: the human being and God. It begins with an overview of the characteristics of the human individual and the context in which they must live out their lives, a context dominated by two seemingly contradictory realities: the existence of God and the existence of evil.

Contributed articles on self-realization.

In this paper I systematically reconstruct Hegel’s concept of “free mechanism” as developed in the Science of Logic. The term “free mechanism” appears absurd since each of the terms constituting it appears mutually exclusive. I argue that we may grasp it only on (1) the assumption of self-reference and (2) via a triad of syllogisms, which altogether constitute a process of alternating middle terms. On the whole, I employ Hegel’s account of “free mechanism” to illuminate the activity of objectivity, whereby (...) the self-determining concept resurrects itself from its dormancy in an indifferent totality. (shrink)

HSÜN Tzu's essay on "Rectifying Terms" is justly considered a work of "great logical interest." For in this essay, one finds a remarkably modern concern with such topics as the rationale for having terms; the empirical and pragmatic bases for the classification of terms; the formation of generic and specific terms; the importance of observing established linguistic practices; the necessity of complying with proper standards for the institution, ratification, and regulation of the uses of language ; the nature of argumentative (...) discourse ; and the problems inherent in successful linguistic communication. A careful examination of some passages in other essays also suggests an awareness of the distinction between deductive, inductive, and analogical inferences, though Hsün Tzu provides us no explicit discussion of the nature of reasoning and its validating rules. (shrink)

The outline of modern macroeconomics took shape in Britain in the early nineteenth century thanks, in part, to David Ricardo, one of the most influential economists of the time. Britain was challenged by monetary inflation, industrial unemployment and the loss of jobs abroad. Ricardo pointed the way forward. As a financier and Member of Parliament, he was well versed in politics and commercial affairs. His expertise is shown by the practicality of his proposals, including the resumption of the gold standard, (...) which was essential given the destabilizing policy of the Bank of England. Ricardo's expertise appears also in his debate with T. R. Malthus about whether an industrial economy can suffer a prolonged depression. Say's Law of Markets and the Quantity Theory of Money figure prominently in his works, but not in an extreme form. He was instead a subtle theorist, recognizing the non-neutrality of money, trade depressions and unemployment. (shrink)