Academic literature on the topic 'Sensible qualities'

Abstract I develop a view of perception that does justice to Price's intuition that all sensory experience acquaints us with sensible qualities like colour and shape. Contrary to the received opinion, I argue that we can respect this intuition while insisting that ordinary perception puts us in direct contact with the mind-independent world. In other words, Price's intuition is compatible with naïve realism. Both hallucinations and ordinary perceptions acquaint us with instances of the same kinds of sensible qualities. While the instances in hallucination are mind-dependent, those in veridical perception are not. The latter are ontologically over-determined—they have their existence guaranteed both in virtue of having a material bearer and in virtue of being perceived by a mind. Such over-determined instances are mind-independent—they can continue to exist unperceived, because, in addition to the minds that perceive them, their existence is guaranteed by the material objects that are their bearers.

AbstractThis paper addresses the question of whether, according to Plato, there are forms of sensible qualities; it is also addressed to the wider question of whether there are forms of physical and material things more generally. In particular, it considers the tension raised by the following theses: (1) a Platonic form is the essence of some thing; (2) for Plato those essences that are forms are imperceptible and are knowable through reasoning alone; (3) knowing the essence of a particular color (e.g., red) requires presentation with the relevant perceptible quality and hence requires sense perception; and (4) if a sense perceptible quality has an essence, then that essence is a form. The solution I defend to this puzzle basically consists of accepting theses (1) through (3) but denying thesis (4). Sensible qualities, according to Plato, do have essences, but specifying their essences does not require that one postulate a separate form.

La thèse porte sur l'un des sujets les moins étudiés de la philosophie de la nature aristotélicienne latine médiévale (ca. 1250-ca. 1350), à savoir le soi-disant sujet des "minima sensibilia". Si, comme il est affirmé notamment dans "Physique" VI, les grandeurs sont infiniment divisibles en puissance, un dilemme se pose quant aux limites de divisibilité des qualités sensibles à travers la division de la matière (considérée comme une grandeur étendue) à laquelle elles sont unies. Soit les qualités sensibles sont aussi infiniment divisibles en puissance (mais cela implique que les sens doivent avoir un pouvoir infini pour les percevoir, contrairement à un présupposé aristotélicien fondamental concernant les limites de tout pouvoir existant dans la nature), soit elles ne sont pas infiniment divisibles en puissance (dans ce cas, cependant, il y aurait des portions de matière qui ne peuvent être connues ni par les sens ni, évidemment, par l'intellect, et, ce qui est pire, les entités sensibles seraient finalement composées par elles, ce qui est tout à fait inacceptable dans la vision du monde aristotélicienne). Pour résoudre le dilemme, Aristote, au chapitre 6 du "De sensu et sensato" (445b3-446a20), fait usage de la distinction entre acte et puissance, affirmant que les qualités sensibles sont infiniment divisibles en puissance en tant que parties du tout auquel elles appartiennent, mais qu'il y a des quantités minimales de matière qui peuvent exister en acte par elles-mêmes douées de leurs qualités sensibles. La thèse examine la réflexion menée par les commentateurs latins médiévaux au "De sensu et sensato" (toujours lus en relation avec leurs sources grecques et islamiques) sur le sujet des "minima sensibilia", en l'utilisant comme une perspective privilégiée pour étudier à partir d'un point de vue nouveau et original la conception latine médiévale de l'ontologie et de l'épistémologie des qualités sensibles. En effet, à travers un examen attentif du débat (qui s'accompagne d'une reconstruction approfondie de la tradition manuscrite des commentaires latins médiévaux au "De sensu", qui ont jusqu'à présent été largement négligés par les chercheurs), il est démontré que les commentateurs latins médiévaux développèrent progressivement une conception selon laquelle les qualités sensibles peuvent exister par elles-mêmes dans le monde naturel sans être perceptibles en acte en raison de la petitesse de la matière à laquelle elles sont unies. De telles qualités sensibles (que l'on appelle parfois "insensibilia propter parvitatem") peuvent néanmoins devenir perceptibles en acte en s'unissant les unes aux autres. Grâce à ce développement fondamental, non seulement les qualités sensibles commencèrent à être comprises dans une large mesure indépendamment de leur rôle dans la perception, mais le monde sensible devint soudainement beaucoup plus étendu que le monde perceptible par les sens, avec pour conséquence que la confiance en la capacité humaine à connaître sa structure ultime a commença à se désintégrer
The thesis focuses on one of the least studied topics in Medieval Latin Aristotelian natural philosophy (ca. 1250-ca. 1350), i.e., the so-called topic of "minima sensibilia". If, as claimed most notably in "Physics" VI, magnitudes are (potentially) infinitely divisible, a dilemma arises with respect to the limits of the divisibility of sensible qualities through the division of the matter (considered as an extended magnitude) with which they are united. Either sensible qualities are also (potentially) infinitely divisible (but this implies that the senses should have an infinite power in order to perceive them, against a fundamental Aristotelian assumption concerning the limits of every power existing in nature), or they are not (potentially) infinitely divisible (in this case, however, there would be portions of matter that can neither be cognised by the senses nor, evidently, by the intellect, and, what is worse, sensible entities would be ultimately composed of them, something entirely unacceptable in the Aristotelian worldview). To solve the dilemma, Aristotle, in Chapter 6 of the "De sensu et sensato" (445b3-446a20), makes use of the distinction between act and potency, affirming that sensible qualities are infinitely divisible in potency as part of the whole to which they belong, but there are minimal quantities of matter that can exist in act on their own endowed with their sensible qualities. The thesis investigates the reflection conducted by Medieval Latin commentators of the "De sensu et sensato" (always read in connection with their Greek and Islamic sources) on the subject of "minima sensibilia", using it as a privileged gateway to study from a new and original point of view the Medieval Latin conception of the ontology and of the epistemology of sensible qualities. Indeed, through a close scrutiny of the debate (which is accompanied by a thorough reconstruction of the complex manuscript tradition of Medieval Latin "De sensu" commentaries, that have hitherto been largely neglected by scholars) it is demonstrated that Medieval Latin commentators progressively developed a conception according to which sensible qualities can exist on their own in the natural world without being perceptible in act due to the smallness of the matter with which they are united. Such sensible qualities (that are sometimes called "insensibilia propter parvitatem") can, nevertheless, become perceptible in act by uniting with each other. Thanks to this fundamental development, not only sensible qualities started to be understood mostly in autonomy from their role in perception, but the sensible world became suddenly much more extended than the world that can be perceived by the senses, with the consequence that the confidence in the human ability to cognise its ultimate structure began to crumble

By focusing on the First Dialogue’s use of ‘sensible quality’ rather than ‘idea’, we can draw out some important morals that allow us to better appreciate its actual accomplishments. Whereas the Principles is an attack on materialist mechanism primarily via its representative theory of perception, the First Dialogue is an attack on materialist mechanism primarily via its primary/secondary-quality distinction. Viewing the First Dialogue in this light allows us to see it as more effective and insightful than we otherwise might, although it also requires us to acknowledge that Hylas is never as philosophically naïve as Berkeley sometimes seems to suggest.

Pleasures and pains play an important role for Berkeley, not just in motivating action, but also by providing knowledge of the physical world in which we act. This chapter considers the parallels that Berkeley draws between sensible quality perceptions and pleasures/pains. Importantly, Berkeley holds that we can have intuitive or demonstrative knowledge of the existence and nature of the physical world on the basis of our sensory perceptions. His parallel analysis of pleasures and pains thus surprisingly implies that these, too, can provide us with intuitive or demonstrative knowledge of the physical world. Taking pleasures and pains to have an epistemic and cognitive function allows us to reread certain Berkeleyan texts in ways that are illuminating. This includes texts on the laws of nature, which enable us to regulate actions precisely because knowledge of the natural laws involves generalizing over regularities of sensory perceptions, which include pleasures/pains.

The seventeenth century witnesses the demise of two core doctrines in the theory of perception: naïve realism about color, sound, and other sensible qualities and the empirical theory, drawn from Alhacen and Roger Bacon, that underwrote it. Ejecting such sensible qualities from the mind-independent world at once makes for a cleaner ontology, since bodies can now be understood in purely geometrical terms, and spawns a variety of fascinating complications for the philosophy of perception. If sensible qualities are not part of the mind-independent world, just what are they, and what role, if any, do they play in our cognitive economy? We seemingly have to use color to visually experience objects. Do we do so by inferring size, shape, and motion from color? Or is it a purely automatic operation, accomplished by divine decree? This book traces the debate over perceptual experience in early modern France, covering such figures as Antoine Arnauld, Robert Desgabets, and Pierre-Sylvain Régis alongside their better-known countrymen René Descartes and Nicolas Malebranche.

Descartes’s earliest theory of perception attempts to marry the remnants of the Baconian and Aristotelian views while divorcing them from hylomorphism and the innocent view of sensible qualities. Descartes holds the ‘overlap thesis,’ the claim that any behavior exhibited by non-human animals and inattentive humans must receive the same explanation. Corporeal perception requires the presence of a brain image that resembles its object. When the mind attends to its environment, it is immediately aware of this brain image and, through it, of the common sensibles. The claim that the mind ‘turns toward’ the brain is a thoroughly traditional one. The proper sensibles are summoned by the mind on the occasion of its undergoing certain brain events. Descartes thinks of the mind as ‘decoding’ the language of the brain in order to provide itself with the appropriate sensations. But those sensations do nothing to explain our awareness of objects.

Despite its difference in aspiration, the Meditations preserves the basic structure of perceptual experience outlined in Descartes’s earliest works. The chapter explores Descartes’s notion of an idea and uses a developmental reading to clear up the mystery surrounding material falsity. In the third Meditation, our protagonist does not yet know enough about extension in order to be able to tell whether her idea of cold is an idea of a real feature of bodies or merely the idea of a sensation. By the time she reaches the end of her reflections, she has learned that sensible qualities are at most sensations. As in his earliest stages, Descartes believes that the real work of perceiving the geometrical qualities of bodies is done by the brain image, which he persists in calling an ‘idea,’ at least when it is the object of mental awareness.

This chapter examines the crisis of perception as it figures in the work of four of Descartes’s immediate successors: Louis de la Forge, Robert Desgabets, Pierre-Sylvain Régis, and Antoine Arnauld. La Forge opts for a version of Descartes’s last view, which has no place for natural geometry. Desgabets defends a version of Descartes’s earliest view, which requires the mind to turn to the brain image. Régis thinks we sense colors and sounds and the rest and then use these to imagine extension. Arnauld’s case is especially problematic, since he rejects the mind-independent existence of sensible qualities but seems committed to some version of direct realism. He is then left with the question how the mind projects these illusory states on to extended bodies, a question for which he has no answer.

This chapter traces competing theories of universal natures found in Locke’s Essay and Leibniz’s Nouveaux Essais. Locke maintains that kinds must be defined more or less as we see fit, because nature does not exhibit a reasonably precise or fully determinate division of things and there are no eternal archetypes. His theory of kinds is homocentric. It cedes no authority or priority to general truths or ideas over particular ones. By contrast, Leibniz argues that similarity relations are objective eternal essences of kinds. Their reality consists in being possible entities known by God. Concepts are formed by human minds in virtue of innate tendencies to construct sensible representations of essences. He maintains that knowledge of general principles is prior to knowledge of their particular instances. Leibniz considers dimensions (space, time) to be sort of universals with reality like that of essences. For Locke, ideas of space and time are constructed from particular ideas of spatial and temporal qualities.

How is it that words (such as “Aristotle”) come to stand for the things they stand for (such as Aristotle)? Is the thing that a word stands for, its reference, fully identified or described by conventions known to the users of the word? Or is there a more roundabout relation between the reference of a word and the conventions that determine or fix it? Do words like “water,” “three,” and “red” refer to appropriate things, just as the word “Aristotle” refers to Aristotle? If so, which things are these, and how do they come to be referred to by those words? In Roads to Reference, Mario Gómez-Torrente provides novel answers to these and other questions that have been of traditional interest in the theory of reference. The book introduces a number of cases of apparent indeterminacy of reference for proper names, demonstratives, and natural kind terms, which suggest that reference-fixing conventions for them adopt the form of lists of merely sufficient conditions for reference and reference failure. Arguments are then provided for a new anti-descriptivist picture of those kinds of words, according to which the reference-fixing conventions for them do not describe their reference. The book also defends realist and objectivist accounts of the reference of ordinary natural kind nouns, numerals, and adjectives for sensible qualities. According to these accounts, these words refer, respectively, to “ordinary kinds,” cardinality properties, and properties of membership in intervals of sensible dimensions, and these things are fixed in subtle ways by associated reference-fixing conventions.

This chapter proposes a picture of reference fixing for color adjectives and adjectives for other sensible qualities, according to which the relevant reference-fixing conventions allow those adjectives to be used with different intended standards in different contexts. It is argued that this explains the fact (used by secondary-quality theorists and eliminativists in “perceptual variation arguments”) that different equally normal people classify the same object by means of prima facie incompatible color adjectives, and that the explanation is perfectly compatible with the properties referred to by uses of these adjectives being primary qualities or objective properties. It is also argued that the picture satisfies a number of desiderata not satisfied by other objectivist theories in the literature.

Abstract Schopenhauer’s World as Will and Representation defends an idealism according to which space and time have no reality beyond the world of representation; both are “forms of knowledge, not qualities of the thing in itself.” The locus classicus of such idealism is Kant’s Critique of Pure Reason, a work regarded by Schopenhauer as the most important contribution to philosophy in two thousand years. He claims that Kant’s arguments for idealism, by wholly conquering the innate realism of our original disposition, produce an effect “like that of an operation for cataract on a blind man.” This epiphany is occasioned by the book’s Transcendental Aesthetic chapter, whose proofs have “a complete power of conviction,” and whose propositions “number among the incontestable truths.” Schopenhauer’s praise of Kant here is striking, not least because a broad consensus over two centuries has concluded that the Transcendental Aesthetic’s central argument for its idealist theory of space and time is a clear failure. Schopenhauer’s positive appraisal is usually taken to show that he too simply overlooked the fatal objection to the argument. It is argued that Schopenhauer saw exactly why the classical invalidity objection is mistaken—that he praised Kant’s argument for transcendental idealism because he understood it. His insight leads us to a deeper understanding of one of the pivotal arguments of Kant’s critical philosophy.

Abstract ‘Philosophy scarcely ever advances a greater paradox in the eyes of the people than when it affirms that Snow is neither cold nor white: Fire neither hot nor red.’ So wrote Hume on 4 July 1762; and he commented on the great ‘pains’ it had cost Malebranche and Locke to establish that ‘the Sensible Qualities of Heat, Smell, Sound and Colour’ are ‘not really in Bodies’. What Hume had in mind was Malebranche’s vigorous attack on the ‘error’ whereby almost everyone believes that ‘heat is in the fire ... and colours in coloured objects’ (Recherche de la vérité[1674], bk. I ch. xi), and Locke’s assault on the ‘vulgar’ way of talking ‘as if Light and Heat were really something in the Fire more than a power to excite [certain] Ideas in us’ (Essay concerning Human Understanding [1670], bk. II ch. xxxi §2). But Hume might have gone back further. For both Malebranche and, whether directly or indirectly, Locke, were powerfully influenced in their attitude to colour and other sensible qualities, by the arguments of RenéDescartes. It is the contribution of Descartes to what we now know as the ‘secondary qualities’ tradition that will be the main theme of this chapter.

Future manned missions to Mars are expected to greatly increase the space vehicle’s size, weight, and heat dissipation requirements. An effective means to reducing both size and weight is to replace single-phase thermal management systems with two-phase counterparts that capitalize upon both latent and sensible heat of the coolant rather than sensible heat alone. This shift is expected to yield orders of magnitude enhancements in flow boiling and condensation heat transfer coefficients. A major challenge to this shift is a lack of reliable tools for accurate prediction of two-phase pressure drop and heat transfer coefficient in reduced gravity. Developing such tools will require a sophisticated experimental facility to enable investigators to perform both flow boiling and condensation experiments in microgravity in pursuit of reliable databases. This study will discuss the development of the Flow Boiling and Condensation Experiment (FBCE) for the International Space Station (ISS), which was initiated in 2012 in collaboration between Purdue University and NASA Glenn Research Center. This facility was recently tested in parabolic flight to acquire condensation data for FC-72 in microgravity, aided by high-speed video analysis of interfacial structure of the condensation film. The condensation is achieved by rejecting heat to a counter flow of water, and experiments were performed at different mass velocities of FC-72 and water and different FC-72 inlet qualities. It is shown that the film flow varies from smooth-laminar to wavy-laminar and ultimately turbulent with increasing FC-72 mass velocity. The heat transfer coefficient is highest near the inlet of the condensation tube, where the film is thinnest, and decreases monotonically along the tube, except for high FC-72 mass velocities, where the heat transfer coefficient is enhanced downstream. This enhancement is attributed to both turbulence and increased interfacial waviness. One-ge correlations are shown to predict the average condensation heat transfer coefficient with varying degrees of success, and a recent correlation is identified for its superior predictive capability, evidenced by a mean absolute error of 21.7%.

The CO2 transcritical Rankine power cycle has been widely investigated recently, because of its better temperature glide matching between sensible heat source and working fluid in vapor generator, and its desirable qualities, such as moderate critical point, little environment impact and low cost. A reheat CO2 transcritical power cycle with two stage expansion is presented to improve baseline cycle performance in this paper. Energy and exergy analysis are carried out to investigate parametric effects on cycle performance. The main results show that reheat cycle performance is sensitive to the medium pressures and the optimum pressures exist for maximizing net work output and thermal efficiency, respectively. Reheat cycle is compared to baseline cycle under the same conditions. More significant improvements by reheat are obtained at lower turbine inlet temperatures and/or larger high cycle pressure. Work output improvement is much higher than thermal efficiency improvement, because extra waste heat is required to reheat CO2. Based on second law analysis, exergy efficiency of reheat cycle is also higher than that of baseline cycle, because more useful work is converted from waste heat. Reheat with two stage expansion has great potential to improve thermal efficiency and especially net work output of a CO2 transcritical power cycle using a low-grade heat source.

Bottom ash from Municipal Waste fired boilers have sufficient heat content and this can be used to pre-heat the boiler feed water or the combustion air. A study of the recent developments in this area is done with a focus on the air based cooling method. Modeling and simulation of the thermal performance of an air cooled ash cooling system is done with the help of Gambit/Fluent software. Among several methods of waste disposal, incineration of Municipal Waste is opted mainly due to its energy potential and specific advantages like high volume reduction ratio and convenience in plant location. However, the inherent fuel qualities that confront this method are its high moisture and ash content and the consequent low calorific values. The fuel bed temperature in stoker fired incineration systems can reach up to 1200K and a considerable part of this heat is wasted by way of ash sensible heat loss. The methods used for ash cooling include the water cooled ash screw system, the rolling cylinder ash cooler, fluidized bed ash cooler and the high strength steel belt ash cooler. In this study, the simulation of the performance of water based and air based ash cooling systems is done for a certain municipal waste fired boiler. The effect of the two methods on the overall boiler efficiency is studied. Comparison of results with that of a working system indicates that air cooling systems can be as efficient as the water cooled systems. With the help of this study, bottom ash heat recovery, especially for waste fired boilers, will be appreciated better and power plant designers will have a better insight into this area.