I introduce two new tools in experimental neurobiology, optogenetics and DREADDs. These tools permit unprecedented control over activity in specific neurons in behaving animals. In addition to their inherent scientific interest, these tools make an important contribution to philosophy of science. They illustrate the very premises of Ian Hacking’s “microscope” argument for the relative independence of experiment from theory. This new example is important for generalizing Hacking’s argument because the background sciences and the fields of engineering producing these tools differ (...) significantly. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:The Microscope of Experience: Christian Garve’s Translation of Cicero’s De Officiis (1783)Johan van der ZandeDuring the negotiations leading to the Treaty of Teschen of 1779, ending the phony War of Bavarian Succession, Frederick II and his court stayed in Breslau, the capital of Silesia. There, in conversation with Christian Garve, the city’s most famous son, the king strongly recommended a new German translation of Cicero’s On Moral Duties (De (...) Officiis), one of the classical texts of humanist philosophy and his favorite book. Frederick’s faithful subject dutifully obliged his sovereign. Four years later, in the subservient language of a dedication to a royal patron, Garve offered in due obedience to Frederick a result that, “perhaps flawed,” was “vindicated by the efforts directed toward the execution of the command.” 1Yet Garve’s interest in Cicero differed markedly from that of Frederick. After all, as Garve wrote in the preface to the philosophical commentary on his translation, Cicero’s book was written for “persons of the higher classes who participated in the affairs of state” and for whom “moral prescription often transformed into political instruction.” Clearly that was not the world in which Garve lived. The son of an artisan, Garve, after a brief stint as a professor of philosophy in Leipzig in the early 1770s, was forced by his illness to spend the rest of his life as a reclusive private scholar in his hometown. He admitted that Cicero sometimes “condescended to deal with those classes who occupy themselves as educators and scholars.” The producing classes, however, “this vast, indispensable, and valuable part of humankind,” could only find prescriptions [End Page 75] for the virtuous life in Cicero’s work insofar as they were human beings, not in relation to their station in life. In general terms Garve thought that Cicero had neglected to deal sufficiently with domestic duties, a reproach which he also leveled against another intellectual pedigree, Adam Ferguson. This did not mean, however, that Garve reduced the citizen’s actions to the private sphere, where they could be productive economically and concerned only with their own Bildung. On the contrary, for Garve useful citizens were those who committed themselves to sociability and to political engagement. Moral actions were not only to be judged according to their motivation (as Kant asserted) but also on their effects on society at large.This different emphasis, I suggest, was typical of the German popular philosophers, who in the time span between Christian Wolff and Immanuel Kant formulated a philosophy of life and among whom Garve emerged as the foremost representative. As a group they constituted a philosophical movement in their own right and were not merely, as they are usually described, the popularizers of Wolff’s philosophy. Rather, popular philosophy was a characteristic compound of Wolffian rationalism and British empiricism. Some popular philosophers, mostly the older generation, were more inclined to the rationalist and others, among them Garve, to the empirical end of this spectrum. Little concerned with epistemological problems or with the irrational cult of life as were the life philosophies of the nineteenth century, the popular philosophers were primarily interested in the virtuous life, in a philosophical theory of moral and aesthetic action. Theirs was a “science of man,” that is, a combination of practical philosophy and literary skills with the goal of morally educating a literate but non-specialized public to be useful citizens of the absolute state. They wanted to speak with propriety on all themes of human existence rather than pursue those philosophical questions not directly related to human life. 2 I entirely agree with a recent commentator who describes Garve’s concerns as non-bourgeois, or better, pre-bourgeois and deeply rooted in humanist values. 3This approach shows in Garve’s Cicero translation and commentary. In Leipzig he had attended the lectures of the classical philologist Friedrich Wilhelm Reiz, who trained his students in precise, critical scholarship. When Garve became a professor himself, he and Reiz anonymously published a Latin edition of Aristotle’s Rhetoric. Later, Garve wrote that his own philosophy was indebted to Reiz who had pointed out to him the close relationship between linguistic and... (shrink)

In Part I of this series, we presented the microscopic approach to Souslin-tree constructions, and argued that all known ⋄-based constructions of Souslin trees with various additional properties may be rendered as applications of our approach. In this paper, we show that constructions following the same approach may be carried out even in the absence of ⋄. In particular, we obtain a new weak sufficient condition for the existence of Souslin trees at the level of a strongly inaccessible cardinal. We (...) also present a new construction of a Souslin tree with an ascent path, thereby increasing the consistency strength of such a tree's nonexistence from a Mahlo cardinal to a weakly compact cardinal. Section 2 of this paper is targeted at newcomers with minimal background. It offers a comprehensive exposition of the subject of constructing Souslin trees and the challenges involved. (shrink)

Bas van Fraassen’s recent book Scientific Representation: Paradoxes of Perspective modifies and refines the “constructive empiricism” of The Scientific Image in a number of ways. This paper investigates the changes concerning one of the most controversial aspects of the overall position, that is, van Fraassen’s agnosticism concerning the veridicality of microscopic observation. The paper tries to make plausible that the new formulation of this agnosticism is an advance over the older rendering. The central part of this investigation is an attempt (...) to answer Marc Alspector-Kelly’s 2004-criticism of an early version of van Fraassen’s new position. Alspector-Kelly’s contribution it is to date the most extensive attack on van Fraassen’s twenty-first-century work on the topic of microscopic observation. One of the central ideas emerging from the present discussion is a link between the debate over the veridicality of microscopic observation and the issue of the theory-ladenness of experience. (shrink)

The increasing concern about visual representation in science has been usually converged on representations – photographs, diagrams, graphs, maps –, while instruments of visualization have been usually neglected, even because of the concrete difficulty to grasp their effects on visualization. In this regard, the questions and concepts formulated in the debate on digital visualization deserve here as a starting point to analyze the change in instrumental mediation triggered by the introduction of computer-assisted imaging technologies in those laboratories that traditionally have (...) used and still use microscopes. Empirical materials gathered during an ethnographic investigation of Italian cytogenetics labs are here presented to show the visual spaces provided by microscopes and digital systems as activity fields, which are inhabited by and suggest in an either divergent or complementary way specific practices, materials, organizations, epistemological orientations and aesthetical preferences. (shrink)

Legendre transform between thermodynamic quantities such as the Helmholtz free energy and entropy plays a key role in the formulation of the canonical ensemble. In the standard treatment, the transform exchanges the independent variable from the system’s internal energy to its conjugate variable—the inverse temperature of the heat reservoir. In this article, we formulate a microscopic version of the transform between the free energy and Shannon entropy of the system, where the conjugate variables are the microstate probabilities and the energies (...) (scaled by the inverse temperature). The present approach gives a non-conventional perspective on the connection between information-theoretic measure of entropy and thermodynamic entropy. We focus on the exact differential property of Shannon entropy, utilizing it to derive central relations within the canonical ensemble. Thermodynamics of a system in contact with the heat reservoir is discussed in this framework. Other approaches, in particular, Jaynes’ maximum entropy principle is compared with the present approach. (shrink)

It is conventional to try to arrive at the Boltzmann principle and the Second Law starting with the laws of dynamics at the microscopic level. In this article the opposite view is presented: Starting with the Second Law, microscopic properties are derived. A classical result of Wien is developed into a general theorem, and the possibility of deriving the Boltzmann principle as a consequence of Carnot's theorem is discussed.

In lieu of an abstract, here is a brief excerpt of the content:The Microscope of Experience: Christian Garve’s Translation of Cicero’s De Officiis (1783)Johan van der ZandeDuring the negotiations leading to the Treaty of Teschen of 1779, ending the phony War of Bavarian Succession, Frederick II and his court stayed in Breslau, the capital of Silesia. There, in conversation with Christian Garve, the city’s most famous son, the king strongly recommended a new German translation of Cicero’s On Moral Duties (De (...) Officiis), one of the classical texts of humanist philosophy and his favorite book. Frederick’s faithful subject dutifully obliged his sovereign. Four years later, in the subservient language of a dedication to a royal patron, Garve offered in due obedience to Frederick a result that, “perhaps flawed,” was “vindicated by the efforts directed toward the execution of the command.” 1Yet Garve’s interest in Cicero differed markedly from that of Frederick. After all, as Garve wrote in the preface to the philosophical commentary on his translation, Cicero’s book was written for “persons of the higher classes who participated in the affairs of state” and for whom “moral prescription often transformed into political instruction.” Clearly that was not the world in which Garve lived. The son of an artisan, Garve, after a brief stint as a professor of philosophy in Leipzig in the early 1770s, was forced by his illness to spend the rest of his life as a reclusive private scholar in his hometown. He admitted that Cicero sometimes “condescended to deal with those classes who occupy themselves as educators and scholars.” The producing classes, however, “this vast, indispensable, and valuable part of humankind,” could only find prescriptions [End Page 75] for the virtuous life in Cicero’s work insofar as they were human beings, not in relation to their station in life. In general terms Garve thought that Cicero had neglected to deal sufficiently with domestic duties, a reproach which he also leveled against another intellectual pedigree, Adam Ferguson. This did not mean, however, that Garve reduced the citizen’s actions to the private sphere, where they could be productive economically and concerned only with their own Bildung. On the contrary, for Garve useful citizens were those who committed themselves to sociability and to political engagement. Moral actions were not only to be judged according to their motivation (as Kant asserted) but also on their effects on society at large.This different emphasis, I suggest, was typical of the German popular philosophers, who in the time span between Christian Wolff and Immanuel Kant formulated a philosophy of life and among whom Garve emerged as the foremost representative. As a group they constituted a philosophical movement in their own right and were not merely, as they are usually described, the popularizers of Wolff’s philosophy. Rather, popular philosophy was a characteristic compound of Wolffian rationalism and British empiricism. Some popular philosophers, mostly the older generation, were more inclined to the rationalist and others, among them Garve, to the empirical end of this spectrum. Little concerned with epistemological problems or with the irrational cult of life as were the life philosophies of the nineteenth century, the popular philosophers were primarily interested in the virtuous life, in a philosophical theory of moral and aesthetic action. Theirs was a “science of man,” that is, a combination of practical philosophy and literary skills with the goal of morally educating a literate but non-specialized public to be useful citizens of the absolute state. They wanted to speak with propriety on all themes of human existence rather than pursue those philosophical questions not directly related to human life. 2 I entirely agree with a recent commentator who describes Garve’s concerns as non-bourgeois, or better, pre-bourgeois and deeply rooted in humanist values. 3This approach shows in Garve’s Cicero translation and commentary. In Leipzig he had attended the lectures of the classical philologist Friedrich Wilhelm Reiz, who trained his students in precise, critical scholarship. When Garve became a professor himself, he and Reiz anonymously published a Latin edition of Aristotle’s Rhetoric. Later, Garve wrote that his own philosophy was indebted to Reiz who had pointed out to him the close relationship between linguistic and... (shrink)

Some of the physical implications involved in self-consistently selecting a superconducting (nonequivalent) representation for the BCS Hamiltonian are developed and discussed. This is done by comparing the phase symmetry of our system in original variables with that same symmetry when written in terms of physical variables. It is shown explicitly that Goldstone's theorem is satisfied and that dynamical rearrangement of symmetry has taken place in going from original to physical variables. Thus, it is found that the original phase symmetry transformation (...) is taken up by physical “massless” fields and that the Bose-Einstein condensations of these fields in the physical (superconducting) ground state produce the asymmetry by “printing” the quantum electron numbern on that state. (shrink)

A system of nonlinear integro-differential equations is derived for the motion of the classical electron with a rigid and spherically symmetric 3D gaussian distribution of charge. The equations are analyzed for stability around the state of rest and of uniform rectilinear motion with velocity small with respect to the velocity of light. The extremely high-frequency and radiationless micro-oscillations that the electron executes when disturbed from the equilibrium states show the inconsistency of the Abraham-Lorentz equation and of all concepts associated with (...) this equation, like the notion that the electron may have a mass of electromagnetic origin. (shrink)

Classically, an osculating circle at a point of a planar curve is introduced technically, often with formula giving its radius and the coordinates of its center. In this note, we propose a new and intuitive definition of this concept: among all the circles which have, on the considered point, the same tangent as the studied curve and thus seem equal to the curve through a microscope, the osculating circle is this that seems equal to the curve through a microscope within (...) microscope. (shrink)

Comme la nova de 1604 et les trois comètes de 1618, qui engagèrent Galilée et les jésuites du Collège romain dans un long débat, la comète de 1664 a relancé la curiosité et l'attente des astronomes et des astrologues. L'article analyse quelques aspects de ce débat européen, en se focalisant sur l'observatoire de l'école de Santa-Lucia de Bologne, où Giovan Battista Riccioli et ses «associés» avaient, depuis longtemps, développé une activité expérimentale connue dans toute l'Europe pour sa précision. Il étudie (...) ensuite la renaissance des scientiae mediae, c'est-à-dire principalement la géographie et l'hydrométrie, en cherchant à éclairer les conditions socioculturelles dans lesquelles de nouvelles figures professionnelles, comme celles de l'ingénieur et du technicien, ont pris naissance dans la Bologne du XVIe siècle. (shrink)

According to Stephen Davies, there is no such thing as free beauty. Using actual and imaginary examples, he tries to show that our aesthetic evaluations of objects inevitably pay heed to the kinds to which they belong or in which we judge them to belong. His examples are not as compelling as he thinks, however. Furthermore, nature looked at through a microscope (or a telescope) provides us with a particular class of counter-examples which have not been dealt with by Davies (...) and which put considerable pressure on his account. (shrink)

In the seventeenth century the microscope opened up a new world of observation, and, according to Catherine Wilson, profoundly revised the thinking of scientists and philosophers alike. The interior of nature, once closed off to both sympathetic intuition and direct perception, was now accessible with the help of optical instruments. The microscope led to a conception of science as an objective, procedure-driven mode of inquiry and renewed interest in atomism and mechanism. Focusing on the earliest forays into microscopical research, from (...) 1620 to 1720, this book provides us with both a compelling technological history and a lively assessment of the new knowledge that helped launch philosophy into the modern era. Wilson argues that the discovery of the microworld--and the apparent role of living animalcula in generation, contagion, and disease--presented metaphysicians with the task of reconciling the ubiquity of life with human-centered theological systems. It was also a source of problems for philosophers concerned with essences, qualities, and the limits of human knowledge, whose positions are echoed in current debates about realism and instrument-mediated knowledge. Covering the contributions of pioneering microscopists (Leeuwenhoek, Swammerdam, Malpighi, Grew, and Hooke) and the work of philosophers interested in the microworld (Bacon, Descartes, Leibniz, Malebranche, Locke, and Berkeley), she challenges historians who view the abstract sciences as the sole catalyst of the Scientific Revolution as she stresses the importance of observational and experimental science to the modern intellect. (shrink)

In this paper I will compare two conceptions of basic elements or units of living organisms from the second half of the nineteenth century: Goodsir’s cellular centers and Bütschli’s protoplam. The comparison will be made from the proposition of a nucleoplasmic form, and the referred conceptions are historical expressions of this general form. The nutrition center is a form that combines the functions of nutrition, germination and reproduction, responsible for the production of tissues, organs, tumors and the whole organism from (...) the fertilized egg. Microscopic foams produce organic differentiation through dynamic stabilization of the surface tension between the alveoli. I will conclude critically by discussing the relationship of these two expressions in terms of their continuity or exhaustion as scientific achievements of the biology of the period cited. (shrink)

In this commentary, the microscopic animals of the genus Rotifera, or “rotifers,” emerge as a theory-provoking nonhuman animal. Rotifers embody otherness in ways that may intrigue scholars within both Human-Animal Studies and feminist science studies. In their encounter with rotifers, such fields of research might also engage each other in new, unexpected, and fruitful ways, as is here argued.

Quantum entanglement lies at the foundation of quantum mechanics. Witness Schrödinger highlighting entanglement with his puzzling cat thought experiment and Einstein deriding it as “spooky action at a distance.” Nonetheless, quantum entanglement has been verified experimentally and is essential for quantum information and quantum computing. The quantum superposition principle, together with entanglement, dramatically contrasts the quantum from the classical description of reality. We attempt to integrate physical reality with a Christian worldview.

Founding our analysis on the Geneva-Brussels approach to quantum mechanics, we use conventional macroscopic objects as guiding examples to clarify the content of two important results of the beginning of twentieth century: Einstein–Podolsky–Rosen’s reality criterion and Heisenberg’s uncertainty principle. We then use them in combination to show that our widespread belief in the existence of microscopic particles is only the result of a cognitive illusion, as microscopic particles are not particles, but are instead the ephemeral spatial and local manifestations of (...) non-spatial and non-local entities. (shrink)

In effort to investigate how quantum physics might modify Einstein's Theory of Relativity at speeds v→c, the relationship between space-time coordinates of different reference frames is revisited by introducing only one new parameter xo, a fundamental constant for the quantization of space. The starting point is three criteria: (a) real space-time data are conditioned by standard quantum effects on measurements; (b) since currently used apparatus are only capable of probing the aggregate behavior of these quanta the relevant model is one (...) which maximizes the Entropy subject to certain defining constraints; and (c) the constraints simply involve fixed ensemble averages in the case of an inertial frame, or boundary conditions on running averages in the case of an accelerated frame. In this context it is found that both the Lorentz transformation and a simple scheme for the quantization of space-time which resembles identically Planck's photon picture of radiation are a direct consequence of the Principle of Relativity. Non-inertial behavior corresponds to local Entropy maxima, obtainable by solution of a diffusion equation which gives gradually varying ensemble averages across space-time, as demonstrated by the example of a profile which connects a central region of highly agitated quanta with an asymptotic ambient environment—the outcome is the Schwarzschild metric of General Relativity. Apart from the above, a new feature emerges from the theory: the space-time data of an observer, when referred to the frame of his moving partner, are subject to extra quantum fluctuations which increase indefinitely in severity as v→c, with the Lorentz transformation providing only the mean data values. Thus for fast moving bodies like cosmic rays or matter at the horizon of a black hole, physical processes which affect them may not always be perceived by us to occur at the expected length or time scales. (shrink)

El microscopio constituye un instrumento de vital importancia para la Microbiología y para muchas otras ramas de la Medicina. Se realizó una revisión bibliográfica con el objetivo de profundizar los conocimientos sobre el microscopio, sobre la historia de este en el período comprendido desde su creación hasta la actualidad a nivel mundial y más brevemente en Cuba. El trabajo aborda también, con una corta descripción, los diferentes tipos existentes, así como algunas de las aplicaciones más importantes en la Microbiología. This (...) bibliographic review was carried out with the objective to deepen the existing knowledge about the history of the microscope since its origin up to date worldwide which and in Cuba, taking into account that it constitutes an instrument of vital importance for microbiology and for many other branches of medicine. This work also deals with a brief description of the different types of microscopes as well as some of the most important applications in microbiology. (shrink)

SUMMARYThis paper discusses the scientific instruments made and used by the microscopist Antony van Leeuwenhoek. The immediate cause of our study was the discovery of an overlooked document from the Delft archive: an inventory of the possessions that were left in 1745 after the death of Leeuwenhoek's daughter Maria. This list sums up which tools and scientific instruments Leeuwenhoek possessed at the end of his life, including his famous microscopes. This information, combined with the results of earlier historical research, (...) gives us new insights about the way Leeuwenhoek began his lens grinding and how eventually he made his best lenses. It also teaches us more about Leeuwenhoek's work as a surveyor and a wine gauger.A further investigation of the 1747 sale of Leeuwenhoek's 531 single lens microscopes has not only led us to the identification of nearly all buyers, but also has provided us with some explanation about why only a dozen of this large number of microscopes has survived. (shrink)