The paper presents a preliminary estimation of the extent of dissemination of optical texts, ideas, and issues among the masters connected with the Prague faculty of arts in the late 14th and early 15th century. Investigation of this topic, so far rather neglected, is based chiefly on manuscript research. The paper brings evidence that perspectiva was taught in Prague at least since the 1370s. It suggests that investigation of Prague quodlibetal disputations (ca. 1390s – 1410s) and consideration of perspectivist authorities (...) employed in these texts can also shed some light on the issue. However, the paper is mainly devoted to the question on the mechanism of vision disputed by Bohemian arts master John of Borotín (Iohannes de Borotin, 1378 – after 1458) in the quodlibet organised by John Hus in 1411. It is suggested that the single extant exemplar of the question (preserved in the codex Prague, National Library, X.H.18) probably is Borotín’s autograph. The structure and sources of the question are analysed, with the conclusion being that Borotín proposes a compromise between intromission and extramission influenced by John Peckham’s Perspectiva communis. A critical edition of Borotín’s question is appended to the paper. / / / Please note this article is published with Brepols Publishers as a Gold Open Access article under a Creative Commons CC 4.0: BY-NC license. The article is also freely available on the website of Brepols Publishers under this same license. (shrink)

Nineteenth-century optical toys that showcase illusions of motion such as the phenakistoscope, zoetrope, and praxinoscope, have enjoyed active “afterlives” in the twentieth and twenty-first centuries. Contemporary incarnations of the zoetrope are frequently found in the realms of fine art and advertising, and they are often much larger than their nineteenth-century counterparts. This article argues that modern-day optical toys are able to conjure feelings of wonder and spectacle equivalent to their nineteenth-century antecedents because of their adjustment in scale. Exploring a range (...) of contemporary philosophical toys found in arts, entertainment, and advertising contexts, the article discusses various technical adjustments made to successfully “scale up” optical toys, including the replacement of hand-spun mechanisms with larger sources of motion and the use of various means such as architectural features and stroboscopic lights to replace traditional shutter mechanisms such as the zoetrope’s dark slots. Critical consideration of scale as a central feature of these installations reconfigures the relationship between audience and device. Large-scale adaptations of optical toys revise the traditional conception of the user, who is able to tactilely manipulate and interact with the apparatus, instead positing a viewer who has less control over the illusion’s operation and is instead a captive audience surrounded by the animation. It is primarily through their adaptation of scale that contemporary zoetropes successfully elicit wonder as scientific spectacles from their audiences today. (shrink)

Van Eyck: An Optical RevolutionMuseum of Fine Arts, Ghent, Belgium, 1 February–30 April 2020.

Solar power is a very important source of renewable energy for many low power systems. Matching the power consumption level with the supply level can make a great difference in the efficiency of power utilization. MoSe2, crystals (photo-electrodes) have been grown via a direct vapour transport technique. This paper presents results of Photo Voltage (VPh) Vs. Photo current (IPh)curves measured for MoSe2 crystals of different Intensity levels between 10, 20,…100W/cm2 in Polychromatic as well as Monochromatic light. We finding the Open (...) circuit Voltage (VOC), Short circuit current(ISC), fill factor and photo conversion efficiency (?) of Mose2 crystals. The Photo conversion efficiency of this MoSe2 crystals are less than 0.1% in Polychromatic light but nearly 1% in Monochromatic light H. S. Patel | S. P. Shukla | Hitesh Parmar "Optical Response of MoSe2 Crystals" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-3 , April 2017. (shrink)

The Divine Comedy is a poem of Dante Alighieri representing, allegorically, the journey of a soul towards God, in the framework of Dante’s metaphysics of the divine light. However, besides metaphysics, we can find in the poem several passages concerning the natural phenomena. Here we discuss some them, in order to investigate Dante’s knowledge of Physics and, in particular, of Optics.

Recent advances in neuroimaging technologies have rendered multimodal analysis of operators’ cognitive processes in complex task settings and environments increasingly more practical. In this exploratory study, we utilized optical brain imaging and mobile eye tracking technologies to investigate the behavioral and neurophysiological differences among expert and novice operators while they operated a human-machine interface in normal and adverse conditions. In congruence with related work, we observed that experts tended to have lower prefrontal oxygenation and exhibit gaze patterns that are better (...) aligned with the optimal task sequence with shorter fixation durations as compared to novices. These trends reached statistical significance only in the adverse condition where the operators were prompted with an unexpected error message. Comparisons between hemodynamic and gaze measures before and after the error message indicated that experts’ neurophysiological response to the error involved a systematic increase in bilateral dorsolateral prefrontal cortex (dlPFC) activity accompanied with an increase in fixation durations, which suggests a shift in their attentional state, possibly from routine process execution to problem detection and resolution. The novices’ response was not as strong as that of experts, including a slight increase only in the left dlPFC with a decreasing trend in fixation durations, which is indicative of visual search behavior for possible cues to make sense of the unanticipated situation. A linear discriminant analysis model capitalizing on the covariance structure among hemodynamic and eye movement measures could distinguish experts from novices with 91% accuracy. Despite the small sample size, the performance of the linear discriminant analysis combining eye fixation and dorsolateral oxygenation measures before and after an unexpected event suggests that multimodal approaches may be fruitful for distinguishing novice and expert performance in similar neuroergonomic applications in the field. (shrink)

Recent advances in neuroimaging technologies have rendered multimodal analysis of operators’ cognitive processes in complex task settings and environments increasingly more practical. In this exploratory study, we utilized optical brain imaging and mobile eye tracking technologies to investigate the behavioral and neurophysiological differences among expert and novice operators while they operated a human-machine interface in normal and adverse conditions. In congruence with related work, we observed that experts tended to have lower prefrontal oxygenation and exhibit gaze patterns that are better (...) aligned with the optimal task sequence with shorter fixation durations as compared to novices. These trends reached statistical significance only in the adverse condition where the operators were prompted with an unexpected error message. Comparisons between hemodynamic and gaze measures before and after the error message indicated that experts’ neurophysiological response to the error involved a systematic increase in bilateral dorsolateral prefrontal cortex (dlPFC) activity accompanied with an increase in fixation durations, which suggests a shift in their attentional state, possibly from routine process execution to problem detection and resolution. The novices’ response was not as strong as that of experts, including a slight increase only in the left dlPFC with a decreasing trend in fixation durations, which is indicative of visual search behavior for possible cues to make sense of the unanticipated situation. A linear discriminant analysis model capitalizing on the covariance structure among hemodynamic and eye movement measures could distinguish experts from novices with 91% accuracy. Despite the small sample size, the performance of the linear discriminant analysis combining eye fixation and dorsolateral oxygenation measures before and after an unexpected event suggests that multimodal approaches may be fruitful for distinguishing novice and expert performance in similar neuroergonomic applications in the field. (shrink)

The claim that Galileo Galilei transformed the spyglass into an astronomical instrument has never been disputed and is considered a historical fact. However, the question what was the procedure which Galileo followed is moot, for he did not disclose his research method. On the traditional view, Galileo was guided by experience, more precisely, systematized experience, which was current among northern Italian artisans and men of science. In other words, it was a trial-and-error procedure—no theory was involved. A scientific analysis of (...) the optical properties of Galileo’s first improved spyglass shows that his procedure could not have been an informed extension of the traditional optics of spectacles. We argue that most likely Galileo realized that the objective and the eyepiece form a system and proceeded accordingly. (shrink)

It is discerned what light can bring the recent historical reconstructions of maxwellian optics and electromagnetism unification on the following philosophical/methodological questions. I. Why should one believe that Nature is ultimately simple and that unified theories are more likely to be true? II. What does it mean to say that a theory is unified? III. Why theory unification should be an epistemic virtue? To answer the questions posed genesis and development of Maxwellian electrodynamics are elucidated. It is enunciated that (...) the Maxwellian Revolution is a far more complicated phenomenon than it may be seen in the light of Kuhnian and Lakatosian epistemological models. Correspondingly it is maintained that maxwellian electrodynamics was elaborated in the course of the old pre-maxwellian programmes’ reconciliation: the electrodynamics of Ampére-Weber, the wave theory of Young-Fresnel and Faraday’s programme. To compare the different theoretical schemes springing from the different language games James Maxwell had constructed a peculiar neutral language. Initially it had encompassed the incompressible fluid models; eventually – the vortices ones. The three programmes’ encounter engendered the construction of the hybrid theory at first with an irregular set of theoretical schemes. However, step by step, on revealing and gradual eliminating the contradictions between the programmes involved, the hybrid set is “put into order” (Maxwell’s term). A hierarchy of theoretical schemes starting from ingenious crossbreeds (the displacement current) and up to usual hybrids is set up. After the displacement current construction the interpenetration of the pre-maxwellian programmes begins that marks the commencement of theoretical schemes of optics, electricity and magnetism real unification. Maxwell’s programme surpassed that of Ampére-Weber because it did absorb the ideas of the Ampére-Weber programme, as well as the presuppositions of the programmes of Young-Fresnel and Faraday properly co-ordinating them with each other. But the opposite statement is not true. The Ampére-Weber programme did not assimilate the propositions of the Maxwellian programme. Maxwell’s victory over his rivals became possible because the gist of Maxwell’s unification strategy was formed by Kantian epistemology looked in the light of William Whewell and such representatives of Scottish Enlightenment as Thomas Reid and Sir William Hamilton. Maxwell did put forward as basic synthetic principles the ideas that radically differed from that of Ampére-Weber approach by their open, flexible and contra-ontological, genuinly epistemological, Kantian character. For Maxwell, ether was not the ultimate building block of physical reality, from which all the charges and fields should be constructed. “Action at a distance”, “incompressible fluid”, “molecular vortices”, etc. were contrived analogies for Maxwell, capable only to direct the researcher at the “right” mathematical relations. Key words: J.C. Maxwell, unification of optics and electromagnetism, I. Kant, T. Reid, W. Hamilton . (shrink)

In our initial paper discussing plausible steps toward workable warp drive machines. The following article express our view on this debate. While there are still objections toward existing warp drive proposals, such as by G. Landis, Harold White etc., because they are all based on GTR, nonetheless we think it is possible by starting to see if it is possible to deviate from Newton's third law. And we discuss possible a propulsion method based on negative masses, and discuss how optical (...) diameter drive can be first step for realistic lab-scale version of negative mass propulsion. (shrink)

Semantic essentialism holds that any scientific term that appears in a well-confirmed scientific theory has a fixed kernel of meaning. Semantic essentialism cannot make sense of the strategies scientists use to argue for their views. Newton's central optical expression "light ray" suggests a context-sensitive view of scientific language. On different occasions, Newton's expression could refer to different things depending on his particular argumentative goals - a visible beam, an irreducibly smallest section of propagating light, or a traveling particle of light. (...) Essentialist views are too crude to account for the richness and subtleties present in actual episodes of scientific debate and theory-change. (shrink)

Devices based on organic materials can be mechanically flexible to a large extent because of the loose intermolecular bonds in the nano-electrons created from them. Unlike these organic materials, minerals such as silicon, germanium, and gallium arsenide can be used in the structure of electronic devices only in crystalline states, and in this case, covalent bonds make flexibility impossible in them. Makes. Properties such as strength, flexibility, electrical conductivity, magnetic properties, color, reactivity, etc. Starting to change the properties of the (...) material by shrinking it depends more than anything on the type of material and the desired property. For example, by reducing the dimensions of a material, generally some mechanical properties of the material such as strength are improved. This increase in strength does not happen only in the range of a few nanometers, and the strength of materials of several tens and even hundreds of nanometers may be much higher than the large-scale mass material. On the other hand, the change of some properties such as color and magnetic properties may occur in dimensions of only a few nanometers. (shrink)

The recent advent of high-resolution imaging and force spectroscopy using atomic force mi- croscopy (AFM) in organic and inorganic solutions opens the way to imaging a wide variety of surfaces and their solvent structure. However, to take full advantage of the high resolution and provide signicant new analytical capability, a detailed understanding of the background contrast mechanisms that lead to atomic and molecular resolution is critical. Without a theory that connects the measured force to atomic models of the surface and (...) tip of the microscope, the information that can be distilled from these measurements is limited. Molecular dynamics simulations show that the forces acting on the microscope tip result from the direct interaction between a tip and a surface and are entirely due to the structure of water around the tip and surface. (shrink)

There are many eye diseases but the most two common retinal diseases are Age-Related Macular Degeneration (AMD), which the sharp, central vision and a leading cause of vision loss among people age 50 and older, there are two types of AMD are wet AMD and DRUSEN. Diabetic Macular Edema (DME), which is a complication of diabetes caused by fluid accumulation in the macula that can affect the fovea. If it is left untreated it may cause vision loss. Therefore, early detection (...) of diseases is a critical importance. Our main goal is to help doctors detect these diseases quickly before reaching a late stage of the disease. In ophthalmology, optical coherence tomography (OCT) is critical for evaluating retinal conditions. OCT is an imaging technique used to capture high-resolution cross-sections of the retinas of patient. In this thesis, we review ways and techniques to use deep learning classification of the optical coherence tomography images of diseases from which a Retinal is suffering. The models used to improve patient care are (VGG-16, MobileNet, ResNet-50, Inception V3, and Xception) to reduce costs and allow fast and reliable analysis in large studies. The obtained results are encouraging, since the best model ResNet-50 reaching 96.21% of testing accuracy, which is very useful for doctors, to diagnose retinal diseases. (shrink)

What representational state mediates between perception and action? Bence Nanay says pragmatic representations, which are outputs of perceptual systems. This commits him to the view that optic ataxics face difficulty in performing visually guided arm movements because the relevant perceptual systems output their pragmatic representations incorrectly. Here, I argue that it is not enough to say that pragmatic representations are output incorrectly; we also need to know why they are output that way. Given recent evidence that optic ataxia impairs peripersonal (...) space representation, I argue that pragmatic representations are output incorrectly because the organizing principle of the vision-for-action system is blocked by optic ataxia. I then show how this means that this principle, not pragmatic representations, is the representational state that mediates between perception and action, i.e. the principle, not pragmatic representations, is the immediate mental antecedent of action. (shrink)

This chapter summarizes the reflections of a scientist active in optical communication about the need of ethical considerations in technological research. An optimistic definition of ethics, being the art to make good use of technology, is proposed that emphasizes the necessarily involvement of not only technologists but also experts in humanity. The paper then reviews briefly the research activities of a Dutch national consortium where the author had been involved. This mainly academic research dealt with advanced approaches for ultrafast communication. (...) In the next section an assessment is given of the potential impact of the technological results on society. In order to emphasize the positive aspects and counteract the negative ones, three steps are proposed: (i) create conditions for a dialogue between experts in ethics and technology; (ii) work out scenarios for the introduction of new techniques in society; (iii) anticipate opportunities and threats. Finally the conclusions are presented. (shrink)

Several recent commentators argue that Thomas Hobbes’s account of the nature of science is conventionalist. Engaging in scientific practice on a conventionalist account is more a matter of making sure one connects one term to another properly rather than checking one’s claims, e.g., by experiment. In this paper, I argue that the conventionalist interpretation of Hobbesian science accords neither with Hobbes’s theoretical account in De corpore and Leviathan nor with Hobbes’s scientific practice in De homine and elsewhere. Closely tied to (...) the conventionalist interpretation is the deductivist interpretation, on which it is claimed that Hobbes believed sciences such as optics are deduced from geometry. I argue that Hobbesian science places simplest conceptions as the foundation for geometry and the sciences in which we use geometry, which provides strong evidence against both the conventionalist and deductivist interpretations. (shrink)

Rarely does research in the history and philosophy of science lead to new empirical results, but that is exactly what has happened in one of the essays of this special issue: Rang and Grebe-Ellis have developed new experimental techniques to perform measurements Goethe proposed 217 years ago. These measurements fit neatly with Goethe’s idea of polarity—his complementary spectrum is not only an optical, but also a thermodynamical counterpart of Newton’s spectrum. I use the new measurements, firstly, to argue against the (...) asymmetries between light and darkness posited by Lyre and Schreiber; and, secondly, to explicate the alternative theory that Goethe had introduced to urge scientific pluralism. In my replies to exegetical criticism by Böhler, Hampe and Zemplén, I show that the main goal of Goethe’s Farbenlehre was indeed to expose symmetries between light and darkness. Furthermore, I argue that it is worthwhile to focus on the experiments, arguments and hypotheses of the Farbenlehre, and not merely on rhetorical, narrative or stylistical aspects, as Böhler and Hampe would have it. Goethe’s criticism of Newton is often dismissed, but it is in fact surprisingly relevant today. (shrink)

We show in this paper that the answer to the question in the title is in the negative. In modern optics, Snell’s law of reflection is derived using Leibniz’s calculus method that identifies the least time path, chosen by rays of light in going from a given point A, to another given point B, undergoing reflection at a point P on their way. We demonstrate, taking two examples of reflection: (1) at a plane reflector and (2) at elliptical reflector, (...) that Snell’s law of reflection is not a consequence of least time path principle and, that Leibniz’s method of derivation of Snell’s law of reflection is invalid. In (1), we prove that, if a light ray is reflected at point P on a line, along the least time path APB, then at every point Pi on that line, rays from A are reflected to point B, satisfying Snell’s law. However, paths, APB and APiB do not have equal travel times. In (2), we prove that, if a light ray is reflected along the least time path APB, from focus A to focus B incident at point P on an ellipse, satisfies Snell’s law, then points Pi, not lying on the ellipse, also reflect light rays from A to B, satisfying Snell’s law. However, the paths APB and APiB do not have equal travel times. Thus, both examples prove that least time path is not a criterion for reflection and, that Snell’s law of reflection is not a consequence of least time path principle. (shrink)

In a 2004 paper, “Hume’s Missing Shade of Blue Reconsidered from a Newtonian Perspective,” Eric Schliesser argues that Hume’s well-known discussion of the missing shade of blue “reveals considerable ignorance of Newton’s achievement in optics,” and that Hume has failed to assimilate the lessons taught by Newton’s optical experiments. I argue in this paper, contrary to Schliesser, that Hume’s views on color are logically and evidentially independent of Newton’s results. In developing my reading, I will argue that Schliesser accepts (...) an overly broad interpretation of the implications of Newton’s experimental results, and takes inadequate account of Hume’s disciplined methodological restrictions on the kinds of experiential evidence that are to be admitted in building the foundations of his science of human nature. (shrink)

The ways in which the Aristotelian sciences are related to each other has been discussed in the literature, with some focus on the subalternate sciences. While it is acknowledged that Aristotle, and Plato as well, was concerned as well with how the arts were related to one another, less attention has been paid to Aristotle's views on relationships among the arts. In this paper, I argue that Aristotle's account of the subalternate sciences helps shed light on how Aristotle saw the (...) art of rhetoric relating to dialectic and politics. Initial motivation for comparing rhetoric with the subalternate sciences is Aristotle's use of the language of boundary transgression, germane to the Posterior Analytics, when discussing rhetoric’s boundaries, as well as the language of "over" and "under" found in APo. First, I discuss three passages in Rhetoric Book I and argue that Garver's (1988) account cannot be correct. Second, I look to the subalternate sciences, especially focusing on optics and the distinction between "unqualified" optics and mathematical optics. Third, I discuss rhetoric's dependence on both dialectic and politics. (shrink)

Technology has the power to break the limitations of traditional passive learning and innovate almost all aspects of everyday life with the power of connecting things of the world to the Internet, “Internet of Things (IoT).” IoT is no longer a phenomenon, but it has become a prevalent system in which people, processes, data, and things connect to the Internet and each other. This paper ‘Enhanced Campus Automation System and the emerging need of IoT integration: an automation perspective’ [eCAS-IoT] is (...) an outcome of case study undertaken at St. Aloysius’ College, Jabalpur, India, wherein the automation challenges are taken into consideration that has been integrated in the existing ERP and related tools such as RFID based attendance and monitoring system in real-time, digital library, API integration and implementation of Optical Network. In this paper we have tried to bring out ideas to achieve the campus automation challenges and awareness of greater need of technical expertise, promotion and training on the effective use of ICT and related devices to make teaching, learning and administration more impacting. (shrink)

When it became uncool to speak of beauty with respect to pieces of art, physicists started claiming that their results are beautiful. They say, for example, that a theory's beauty speaks in favour of its truth, and that they strive to perform beautiful experiments. What does that mean? The notion cannot be defined. (It cannot be defined in the arts either). Therefore, I elucidate it with examples of optical experimentation. Desaguliers' white synthesis, for example, is more beautiful than Newton's, and (...) the many colourful syntheses done by Viennese painter Ingo Nussbaumer exemplify even greater beauty. Here are some criteria (which, of course, do not implement a decision procedure concerning beauty in experiments): cleanliness, simplicity, intellectual clarity, symmetry. Similar criteria are relevant to our aesthetical judgements about some pieces of music. So we can assume that our notion of beauty conserning art is related to the one conserning scientific experiments. (shrink)

Hobbes's interest in the power of the Image was programmatic, as suggested by his shifts from optics, to sensationalist psychology, to the strategic use of classical history, exemplified by Thucydides and Homer. It put a great resource at the disposal of the state-propaganda machine, with application to the question of state-management and crowd control.

Nietzsche, in his work On the Genealogy of Morals, argues that human cognition is analogous in certain significant respects to the perspectival nature of optical vision. Because of this analogy, his account of human cognition is often referred to as perspectivism. Brian Leiter argues that Nietzsche’s use of this optical perspective metaphor undermines interpretations that take perspectivism to have radically skeptical implications. In this paper, I examine Leiter’s argument and show that the considerations he raises based on the optical perspective (...) metaphor are insufficient to undermine the claim that perspectivism entails radical skepticism. (shrink)

Alhazen problem of reflection at a concave spherical surface is one of the most discussed problems in optics. It was solved by Alhazen, The number of solution points vary from zero to a maximum of four. However, his solution is known to be prolix. Huygens solved the problem and identified the solution points to be points of intersection of the given circle and a hyperbola. Many other lines of attack were attempted with their solutions. New solutions are offered from (...) time to time. In this paper we offer a solution based on the criterion to be satisfied by reflection of a ray of light at a concave spherical surface. Based on that criterion we show that it is impossible for a circle containing both end points of the path of the ray inside it, to reflect rays from one point to the other. However, for every point on the given circle, we can construct two orthogonal circles (orthogonal conics in general) which reflect rays from one given point to the other, while the given circle is a non-reflector. (shrink)

The chapter deals with misconceptions in perception theory that are based on the idea of slicing the nature of perception along the joints of physics and on corresponding ill-conceived ʹpurposesʹ and ʹgoalsʹ of the perceptual system. It argues that the conceptual structure underlying the percept cannot be inferentially attained from the sensory input. The output of the perceptual system, namely meaningful categories, is evidently vastly underdetermined by the sensory input, namely physico-geometric energy patterns. Thus, the core task of perception theory (...) is to understand the internal conceptual structure with which our perceptual system is endowed. The conceptual structure underlying the semantic distinctions that characterise the output of the perceptual system can, by conceptual necessity, only be expressed by a logical language that is strictly more powerful than the logical language by which sensory notions can be expressed. Consequently, the internal structure underlying perceptual meaning – including core notions such as ‘Gestalt’ or ‘perceptual object’ – cannot be derived, by whatever kind of general inductive machinery, from the sensory input, or, more generally, from experience. (shrink)

Goethe carried out an enormous number of experiments before criticizing Newton's theory of light and colours in the Farbenlehre (1810). He managed to show that Newton's reasoning is based on a rather narrow choice of experiments, in which parameters such as the distance between the prism and the screen are fixed arbitrarily: Newton's famous spectrum (with its green centre) occurs only at a specific distance. Once you reduce the distance, the green centre disappears, and you see the two border spectra (...) instead. Newton can of course explain these border spectra; but things can be explained just as well the other way around: Then you start with a theory based on the two border spectra in order to derive the Newtonian spectrum. Both accounts fit many data (available in Newton and Goethe's days) equally well. Thus by insisting that the step to theory is not forced upon us by "reason and experiments" alone (as Newton would have it), Goethe revealed our own free, creative contribution to theory construction. And surprisingly, his theory of the prismatic colours seems no worse off than Newton's, even taking into account additional criteria of theory choice, such as simplicity or elegance. (shrink)

In the part of the first Critique known as “The Paralogisms of Pure Reason” Kant seeks to explain how even the most acute metaphysicians could have arrived, through speculation, at the ruefully dogmatic conclusion that the self (understood as the subject of thoughts or "thinking I") is a substance. His diagnosis has two components: first, the positing of the phenomenon of “Transcendental Illusion”—an illusion, modelled on but distinct from, optical illusion--that predisposes human beings to accept as sound--and as known to (...) sound--certain in fact flawed arguments for substantive theses about the nature of the self; second, the identification of the fallacy we commit when we succumb to this illusion. It is explained how these two elements combine to produce a central instance of (what Kant sees as) dogmatic speculative metaphysics, namely, the doctrine that the self is a substance in the sense of a necessarily non-inhering subject of inherence. It is argued that Kant has a novel, ingenious, and even somewhat plausible account of the route by which the rational psychologist arrives--or might arrive--at this view, an account that involves identifying a rather deep-rooted confusion about the very nature of conceivability. (shrink)

During the 1630s Descartes recognized that he could not expect all legitimate claims in natural science to meet the standard of absolute certainty. The realization resulted from a change in his physics, which itself arose not through methodological reflections, but through developments in his substantive metaphysical doctrines. Descartes discovered the metaphysical foundations of his physics in 1629-30; as a consequence, the style of explanation employed in his physical writings changed. His early methodological conceptions, as preserved in the Rules and sketched (...) in Part Two of the Discourse, pertained primarily to his early work in optics. By the early 1630s, Descartes was concerned with new methodological problems pertaining to the postulation of micro-mechanisms. Recognition of the need to employ a method of hypothesis led him to lower the standard of certainty required of particular explanations in his mature physics. (shrink)

ABSTRACTAlthough philosophers have often insisted that specular perception is illusory or erroneous in nature, few have stressed the reliability and indispensability of mirrors as optical instrumen...

One of the symbolic images to which Leibniz constantly entrusted the synthesis of his philosophy regards the idea of considering one and the same city from various visual perspectives. Such an image is diffused throughout all Leibniz’s writings and clearly reflects the philosopher’s interest for matters regarding perspective as well as optical phenomena. The point of view of its inhabitants can therefore be compared to a mirror that reflects some different portions of reality. But what do the city-viewers really see? (...) Do they all see exactly the same thing? And assuming the plurality of points of view, how one can be sure that they share the same representative content? The paper presented here tries to offer a plausible interpretation of this topic also by linking different and somehow remote Leibnizian doctrines together. (shrink)

Although George Berkeley himself made no major scientific discoveries, nor formulated any novel theories, he was nonetheless actively concerned with the rapidly evolving science of the early eighteenth century. Berkeley's works display his keen interest in natural philosophy and mathematics from his earliest writings (Arithmetica, 1707) to his latest (Siris, 1744). Moreover, much of his philosophy is fundamentally shaped by his engagement with the science of his time. In Berkeley's best-known philosophical works, the Principles and Dialogues, he sets up his (...) idealistic system in opposition to the materialist mechanism he finds in Descartes and Locke. In De Motu, Berkeley refines and extends his philosophy of science in the context of a critique of the dynamic accounts of motion offered by Newton and Leibniz. And in Siris, Berkeley's flirtation with neo-Platonism draws inspiration from the fire theory of Boerhaave as well as Newton's aetherial speculations in the Queries of the Optics. In examining Berkeley's critical engagement with the natural philosophy of his time, we will thus improve our understanding of not just his philosophy of science, but of his philosophical corpus as a whole. (shrink)

Many of Margaret Cavendish’s criticisms of Thomas Hobbes in the Philosophical Letters (1664) relate to the disorder and damage that she holds would result if Hobbesian pressure were the cause of visual perception. In this paper, I argue that her “two men” thought experiment in Letter IV is aimed at a different goal: to show the explanatory potency of her account. First, I connect Cavendish’s view of visual perception as “patterning” to the “two men” thought experiment in Letter IV. Second, (...) I provide a potential reply on Hobbes’s behalf that appeals to physiological differences between perceivers’ sense organs, drawing upon Hobbes’s optics in De homine. Third, I argue that such a reply would misunderstand Cavendish’s objective of showing the limited explanatory resources available in understanding visual perception as pressing when compared to her view of visual perception as patterning. (shrink)

Is vision merely a state of the beholder’s sensory organ which can be explained as an immediate effect caused by external sensible objects? Or is it rather a successive process in which the observer actively scanning the surrounding environment plays a major part? These two general attitudes towards visual perception were both developed already by ancient thinkers. The former is embraced by natural philosophers (e.g., atomists and Aristotelians) and is often labelled “intromissionist”, based on their assumption that vision is an (...) outcome of the causal influence exerted by an external object upon a sensory organ receiving an entity from the object. The latter attitude to vision as a successive process is rather linked to the “extramissionist” theories of the proponents of geometrical optics (such as Euclid or Ptolemy) who suggest that an entity – a visual ray – is sent forth from the eyes to the object. The present paper focuses on the contributions to this ancient controversy proposed by some 13th-century Latin thinkers. [...]. (shrink)

The title of this piece is meant to evoke at least three sources. The first – and perhaps the only obvious one – concerns the ability of holograms to display parallax, a shifting of visual viewpoint that allows a three-dimensional image to reveal background objects behind those in the foreground. This parallax view is a unique feature of holograms as visual media. A second allusion is to the American film The Parallax View (1974, director A. J. Pakula), a rather paranoid (...) thriller focusing on conspiracy theories concerning government and corporations. To a casual observer, the bare details of the military origins of holography suggest just such cynical and centrally-directed development, although I hope to dispel such simplistic ideas here. And a third passing reference is to the book The Parallax View (2006) by Slavoj Zizek, a wide-ranging and deep exploration of duality in political views, ontological interpretations and scientific methods, among other topics. Zizek’s theme, as well as Pakula’s, is relevant to my approach, which focuses on a parallax of both practice and intent. During the first successful decade of holography, conflicting viewpoints developed between distinct communities: the militarily-guided engineers who invented practical holography, and the later imaging scientists and artisans who stressed three-dimensionality and other attributes instead of the original goal of optical image processing. I argue that distinct groups of users had different perceptions of what holography is and what it is for. (shrink)

Albert Abraham Michelson (1852-1931), the American optical physicist best known for his precise determination of the velocity of light and for his experiments concerning aether drift, is less often acknowledged as the creator of new spectroscopic instrumentation and new spectroscopies. He devised a new method of light analysis relying upon his favourite instrument – a particular configuration of optical interferometer – and published investigations of spectral line separation, Doppler-broadening and simple high-resolution spectra (1887-1898). Contemporaries did not pursue his method. Michelson (...) himself discarded the technique by the end of the decade, promoting a new device, the ‘echelon spectroscope’, as a superior instrument. High-resolution spectroscopy was taken up by others at the turn of the century using the echelon, Fabry-Pérot etalon and similar instruments. Michelson’s ‘Light Wave Analysis’ was largely forgotten, but was rediscovered c1950 and developed over the following three decades into a technique rechristened ‘Fourier transform spectroscopy’. This paper presents Michelson’s interferometric work as a continuum of personal interests and historical context as an example of 'research technology' and 'peripheral science'. (shrink)

This essay develops a concept of curiotization, through which people are reduced to a curio for the fascination of others. I argue that trans people as they have appeared in media, philosophy, and narratives of history are curiotized as forever fascinating, new, titillating, and controversial. In contrast to the narrative of momentous trans progress in the mid-2010s, I point out that frameworks such as the "Transgender Tipping Point" worked to position its "trans moment" as unprecedented and always on the threshold (...) of arrival. To work through a specific example, I point to decades of renewed fascination over trans women being capable of breastfeeding and the long history of trans fascination in popular music. I conclude by emphasizing the obscured world-historical presence of transsexuality as it coincides with the history of pharmaceuticals, hormone technologies, and birth control. In contrast to a "goldfish memory optics" through which trans people become eternally new, fascinating, and debatable, I stress the importance of restoring the complexity of "trans" and its histories back into an understanding of the present. (shrink)

Walter Benjamin’s oft-quoted 1936 essay “The Work of Art in the Age of Its Technological Reproducibility” advances the claim that, for the first time in history, the “function” of the work of art is political, as evidenced by cinema. For Benjamin, film is the “first art form whose artistic character is entirely determined by its reproducibility” and Giorgio Agamben, a contemporary Benjaminian philosopher, further elucidates this “function,” positing that cinema essentially ranks with ethics and politics, not solely with aesthetics, and, (...) consequently, is proximate to philosophy itself. Whereas Deleuze’s Cinema books posed cinema as enacting time in a pure state, Agamben, in his “Notes on Gesture,” breaches from Deleuze’s spatial and cartographic theory of cinema, drawing on Guy Debord’s “détournement via montage,” Simone Weil’s “decreation” and, perhaps most implicitly, from Benjamin. Agamben’s political theory of cinema, motivated by cinema’s “stoppage and repetition of time,” is directly informed by Benjamin’s: “optical unconscious,” appropriation of Brecht’s “social Gestus,” and the relationship between technological reproducibility and aura. Agamben’s “gesture” fastens cinema’s aesthetics not only to ethics and politics, but to the “ontological consistency of human experience,” or to a way of being. (shrink)

Holography, the technology of three-dimensional imaging, has repeatedly been reconceptualised by new communities. Conceived in 1947 as a means of improving electron microscopy, holography was revitalized in the early 1960s by engineer-scientists at classified laboratories. The invention promoted the transformation of a would-be discipline (optical engineering) and spawned limited artist-scientist collaborations. However, a separate artisanal community promoted a distinct countercultural form of holography via a revolutionary technology: the sandbox optical table. Their tools, sponsorship, products, literature and engagement with wider culture (...) differentiated the communities, which instituted a limited ‘technological trade’. The subject strikingly illustrates the co-evolution of new technology along with highly dissimilar user groups, neither of which fostered the secure establishment of a profession or discipline. The case generalises the concept of 'research-technologists' and 'peripheral science', and extends the ideas of Langdon Winner by demonstrating how the political dimensions of a technology can be important but evanescent in the growth of technical communities. (shrink)

Dennis Gabor devised a new concept for optical imaging in 1947 that went by a variety of names over the following decade: holoscopy, wavefront reconstruction, interference microscopy, diffraction microscopy and Gaboroscopy. A well-connected and creative research engineer, Gabor worked actively to publicize and exploit his concept, but the scheme failed to capture the interest of many researchers. Gabor’s theory was repeatedly deemed unintuitive and baffling; the technique was appraised by his contemporaries to be of dubious practicality and, at best, constrained (...) to a narrow branch of science. By the late 1950s, Gabor’s subject had been assessed by its handful of practitioners to be a white elephant. Nevertheless, the concept was later rehabilitated by the research of Emmett Leith and Juris Upatnieks at the University of Michigan, and Yury Denisyuk at the Vavilov Institute in Leningrad. What had been judged a failure was recast as a success: evaluations of Gabor’s work were transformed during the 1960s, when it was represented as the foundation on which to construct the new and distinctly different subject of holography, a re-evaluation that gained the Nobel Prize for Physics for Gabor alone in 1971. This paper focuses on the difficulties experienced in constructing a meaningful subject, a practical application and a viable technical community from Gabor’s ideas during the decade 1947-1957. (shrink)

This essay examines the quantitative aspects of Greco-Roman science, represented by a group of established disci¬plines, which since the fourth century BC were called mathēmata or mathē¬ma¬tikai epistē¬mai. In the group of mathēmata that in Antiquity normally comprised mathematics, mathematical astronomy, harmonics, mechanics and optics, we have also included geography. Using a dataset based on The Encyclopaedia of Ancient Natural Scientists, our essay considers a community of mathēmatikoi (as they called themselves), or ancient scientists (as they are defined for (...) the purposes of the present paper) from a sociological point of view, focusing on the size of the scientific population known to us and its disciplinary, temporal and geographical distribution. A diachronic comparison of neighboring and partly overlapping communities, ancient scientists and philosophers, allows the pattern of their interrelationship to be traced. An examination of centers of science throughout ancient history reveals that there were five major centers – Athens, Alexandria, Rhodes, Rome and Byzantium/Constantinople – that appear and replace one another in succession as leaders. These conclusions serve to reopen the issue of the place of mathēmata and mathēmatikoi in ancient society. (shrink)

A common view in the philosophy of perception holds that states of seeing objects face to face have particular contents. When you see, say, a dog face to face, your visual state represents the particular dog that is in front of you. In this paper, I argue for a related claim about states of seeing objects in conventional photographs. When you see a dog in a photograph, for example, your visual state represents the particular dog that was in front of (...) the camera when the photograph was taken, that is, the photograph's depictum. The argument in this paper proceeds in two steps. In the first step, I discuss states of seeing objects face to face. I argue that such a state represents the particular object whose surface is responsible for the optical information that the visual system uses to construct the state's attributive representational content. In the second step, I apply the result of this discussion to states of seeing objects in photographs. I argue that a state of seeing an object in a photograph has a particular content that represents the object that was in front of the camera when the photograph was taken. (shrink)

Philosophers and psychologists often assume that mirror reflections are optical illusions. According to many authors, what we see in a mirror appears to be behind it. I discuss two strategies to resist this piece of dogma. As I will show, the conviction that mirror reflections are illusions is rooted in a confused conception of the relations between location, direction, and visibility. This conception is unacceptable to those who take seriously the way in which mirrors contribute to our experience of the (...) world. My argument may be read as an advertisement of the neglected field of philosophical catoptrics, the philosophical study of the optical properties of mirrors. It enables us to recast familiar issues in the philosophy of perception. (shrink)

For an Aristotelian observer, the halo is a puzzling phenomenon since it is apparently sublunary, and yet perfectly circular. This paper studies Aristotle's explanation of the halo in Meteorology III 2-3 as an optical illusion, as opposed to a substantial thing (like a cloud), as was thought by his predecessors and even many successors. Aristotle's explanation follows the method of explanation of the Posterior Analytics for "subordinate" or "mixed" mathematical-physical sciences. The accompanying diagram described by Aristotle is one of the (...) earliest lettered geometrical diagrams, in particular of a terrestrial phenomenon, and versions of it can still be found in modern textbooks on meteorological optics. (shrink)

The Cell Ontology (CL) is designed to provide a standardized representation of cell types for data annotation. Currently, the CL employs multiple is_a relations, defining cell types in terms of histological, functional, and lineage properties, and the majority of definitions are written with sufficient generality to hold across multiple species. This approach limits the CL’s utility for cross-species data integration. To address this problem, we developed a method for the ontological representation of cells and applied this method to develop a (...) dendritic cell ontology (DC-CL). DC-CL subtypes are delineated on the basis of surface protein expression, systematically including both species-general and species-specific types and optimizing DC-CL for the analysis of flow cytometry data. This approach brings benefits in the form of increased accuracy, support for reasoning, and interoperability with other ontology resources. 104. Barry Smith, “Toward a Realistic Science of Environments”, Ecological Psychology, 2009, 21 (2), April-June, 121-130. Abstract: The perceptual psychologist J. J. Gibson embraces a radically externalistic view of mind and action. We have, for Gibson, not a Cartesian mind or soul, with its interior theater of contents and the consequent problem of explaining how this mind or soul and its psychological environment can succeed in grasping physical objects external to itself. Rather, we have a perceiving, acting organism, whose perceptions and actions are always already tuned to the parts and moments, the things and surfaces, of its external environment. We describe how on this basis Gibson sought to develop a realist science of environments which will be ‘consistent with physics, mechanics, optics, acoustics, and chemistry’. (shrink)

In this article we introduce the concept of implied optical perspective in deep learning computer vision systems. Taking the BBC's experimental television programme “Made by Machine: When AI met the Archive” as a case study, we trace a conceptual and material link between the system used to automatically “watch” the television archive and a specific type of photographic practice. From a computational aesthetics perspective, we show how deep learning machine vision relies on photography, its technical regimes and epistemic advantages, and (...) we propose a novel way to identify the latent camera through which the BBC archive was seen by machine. (shrink)