We present strategies how to reconstruct (estimate) properties of a quantum channel described by the map E based on incomplete measurements. In a particular case of a qubit channel a complete reconstruction of the map E can be performed via complete tomography of four output states E[ρj] that originate from a set of four linearly independent “test” states ρj (j = 1,2,3,4) at the input of the channel. We study the situation when less than four linearly independent states are transmitted (...) via the channel and measured at the output. We present strategies how to reconstruct the channel when just one, two or three states are transmitted via the channel. In particular, we show that if just one state is transmitted via the channel then the best reconstruction can be achieved when this state is a total mixture described by the density operator ρ = I/2. To improve the reconstruction procedure one has to send via the channel more states. The best strategy is to complement the total mixture with pure states that are mutually orthogonal in the sense of the Bloch-sphere representation. We show that unitary transformations (channels) can be uniquely reconstructed (determined) based on the information of how three properly chosen input states are transformed under the action of the channel. (shrink)

Predictivists use the no miracle argument to argue that “novel” predictions are decisive evidence for theories, while mere accommodation of “old” data cannot confirm to a significant degree. But deductivists claim that since confirmation is a logical theory-data relationship, predicted data cannot confirm more than merely deduced data, and cite historical cases in which known data confirmed theories quite strongly. On the other hand, the advantage of prediction over accommodation is needed by scientific realists to resist Laudan’s criticisms of the (...) no miracle argument. So, if the deductivists are right, the most powerful argument for realism collapses. There seems to be an inescapable contradiction between these prima facie plausible arguments of predictivists and deductivists; but this puzzle can be solved by understanding what exactly counts as novelty, if novel predictions must support the no miracle argument, i.e., if they must be explainable only by the truth of theories. Taking my cues from the use-novelty tradition, I argue that (1) the predicted data must not be used essentially in building the theory or choosing the auxiliary assumptions. This is possible if the theory and its auxiliary assumptions are plausible independently of the predicted data, and I analyze the consequences of this requirement in terms of best explanation of diverse bodies of data. Moreover, the predicted data must be (2) a priori improbable, and (3) heterogeneous to the essentially used data. My proposed notion of novelty, therefore, is not historical, but functional. Hence, deductivists are right that confirmation is independent of time and of historical contingencies such as if the theorist knew a datum, used it, or intended to accommodate it. Predictivists, however, are right that not all consequences confirm equally, and confirmation is not purely a logical theory-data relation, as it crucially involves background epistemic conditions and the notion of best explanation. Conditions (1)–(3) make the difference between prediction and accommodation, and account for the confirming power of theoretical virtues such as non ad-hocness, non-fudging, non-overfitting, independence and consilience. I thus show that functional novelty (a) avoids the deductivist objections to predictivism, (b) is a gradual notion, in accordance with the common intuition that confirmation comes in degrees, and (c) supports the no miracle argument, so vindicating scientific realism. (shrink)

Cómo es posible la historia? -- Giambattista Vico : Una nueva ciencia, la historia (1725) -- Carta de Heidelberg.

L'autore parte dall'analisi dei problemi etici espressi nei linguaggi della poesia, della tragedia e della storiografia, per passare poi alla lettura delle maggiori opere del pensiero antico, fornendo di ognuna puntuali introduzioni. Un'attenzione particolare, alla fine di ogni capitolo, è dedicata all'eredità moderna e al significato attuale dei problemi dell'etica antica, proponendo in modo esplicito un collegamento fra ricostruzione storica e discussione teorica contemporanea.

Most social scientists and philosophers claim that sociology and philosophy are disjoint fields of inquiry. Some have wondered how to trace the precise boundary between them. Mario Bunge argues that the two fields are so entangled with one another that no demarcation is possible or, indeed, desirable. In fact, sociological research has demonstrably philosophical pre-suppositions. In turn, some findings of sociology are bound to correct or enrich the philosophical theories that deal with the world, our knowledge of it, or the (...) ways of acting upon it. While Bunge's thesis would hardly have shocked Mill, Marx, Durkheim, or Weber, it is alien to the current sociological mainstream and dominant philosophical schools. Bunge demonstrates that philosophical problematics arise in social science research. A fertile philosophy of social science unearths critical presuppositions, analyzes key concepts, refines effective research strategies, crafts coherent and realistic syntheses, and identifies important new problems. Bunge examines Marx's and Durkheim's thesis that social facts are as objective as physical facts; the so-called Thomas theorem that refutes the behaviorist thesis that social agents react to social stimuli rather than to the way we perceive them; and Merton's thesis on the ethos of basic science which shows that science and morality are intertwined. He considers selected philosophical problems raised by contemporary social studies and argues forcefully against tolerance of shabby work in academic social science and philosophy alike. (shrink)

Scientists and 'anti-scientists' alike need a more realistic image of science. The traditional mode of research, academic science, is not just a 'method': it is a distinctive culture, whose members win esteem and employment by making public their findings. Fierce competition for credibility is strictly regulated by established practices such as peer review. Highly specialized international communities of independent experts form spontaneously and generate the type of knowledge we call 'scientific' - systematic, theoretical, empirically-tested, quantitative, and so on. Ziman (...) shows that these familiar 'philosophical' features of scientific knowledge are inseparable from the ordinary cognitive capabilities and peculiar social relationships of its producers. This wide-angled close-up of the natural and human sciences recognizes their unique value, whilst revealing the limits of their rationality, reliability, and universal applicability. It also shows how, for better or worse, the new 'post-academic' research culture of teamwork, accountability, etc. is changing these supposedly eternal philosophical characteristics. (shrink)

Why believe in the findings of science? John Ziman argues that scientific knowledge is not uniformly reliable, but rather like a map representing a country we cannot visit. He shows how science has many elements, including alongside its experiments and formulae the language and logic, patterns and preconceptions, facts and fantasies used to illustrate and express its findings. These elements are variously combined by scientists in their explanations of the material world as it lies outside our everyday experience. John (...) Ziman’s book offers at once a valuably clear account and a radically challenging investigation of the credibility of scientific knowledge, searching widely across a range of disciplines for evidence about the perceptions, paradigms and analogies on which all our understanding depends. (shrink)

In this 1976 volume, Professor Ziman paints a broad picture of science, and of its relations to the world in general. He sets the scene by the historical development of scientific research as a profession, the growth of scientific technologies out of the useful arts, the sources of invention and technical innovation, and the advent of Big Science. He then discusses the economics of research and development, the connections between science and war, the nature of science policy and the (...) moral dilemmas of social responsibility in science. Each topic is introduced by reference to easily understandable particular examples, with a large number of illustrations chosen to bring out the concreteness and reality of science as a human activity. Professor Ziman gives a chapter-by-chapter list of suggested topics for oral and written discussion, intended to provoke critical, sceptical attitudes to simplified solutions to real issues, and comments briefly on relevant books and other sources. (shrink)

Ever since Darwin, scholars have noted that cultural entities such as languages, laws and theories seem to evolve through variation, selection and replication. These essays consider whether this comparison is just a metaphor.

A re-evaluation of the notion of vacuum in quantum electrodynamics is presented, focusing on the vacuum of the quantized electromagnetic field. In contrast to the ‘nothingness’ associated to the idea of classical vacuum, subtle aspects are found in relation to the vacuum of the quantized electromagnetic field both at theoretical and experimental levels. These are not the usually called vacuum effects. The view defended here is that the so-called vacuum effects are not due to the ground state of the quantized (...) electromagnetic field. Nevertheless it is possible to maintain an empirically demonstrable notion of vacuum state that is consistent with the interpretation of the formalism of the theory. (shrink)

This fascinating exploration of the great discoveries of history's most important mathematicians seeks an answer to the eternal question: Does mathematics hold the key to understanding the mysteries of the physical world?

It is generally argued that if the wave-function in the de Broglie–Bohm theory is a physical field, it must be a field in configuration space. Nevertheless, it is possible to interpret the wave-function as a multi-field in three-dimensional space. This approach hasn’t received the attention yet it really deserves. The aim of this paper is threefold: first, we show that the wave-function is naturally and straightforwardly construed as a multi-field; second, we show why this interpretation is superior to other interpretations (...) discussed in the literature; third, we clarify common misconceptions. (shrink)

Machine generated contents note: I. METAPHYSICS -- 1. How Do Realism, Materialism, and Dialectics Fare in Contemporary Science? -- 2. New Dialogues between Hylas and Philonous -- 3. Energy: Between Physics and Metaphysics -- 4. The Revival of Causality -- 5. Emergence and the Mind -- 6 SCIENTIFIC REALISM -- 6. The Status of Concepts -- 7. Popper's Unworldly World 3 --II. METHODOLOGY AND PHILOSOPHY OF SCIENCE -- 8. On Method in the Philosophy of Science -- 9. Induction in Science (...) -- 10. The GST Challenge to the Classical Philosophies of Science -- 11. The Power and Limits of Reduction -- 12. Thinking in Metaphors --III. PHILOSOPHY OF MATHEMATICS -- 13. Moderate Mathematical Fictionism -- 14. The Gap between Mathematics and Reality -- 15. Two Faces and Three Masks of Probability --IV. PHILOSOPHY OF PHYSICS -- 16. Physical Relativity and Philosophy -- 17. Hidden Variables, Separability, and Realism -- 18. Schrodinger's Cat Is Dead --V. PHILOSOPHY OF PSYCHOLOGY -- 19. From Mindless Neuroscience and Brainless Psychology to Neuropsychology -- 20. Explaining Creativity -- VI. PHILOSOPHY OF SOCIAL SCIENCE -- 21. Analytic Philosophy of Society and Social Science: -- The Systemic Approach as an Alternative to Holism and Individualism -- 22. Rational Choice Theory: A Critical Look at Its Foundations -- 23. Realism and Antirealism in Social Science --VII. PHILOSOPHY OF TECHNOLOGY -- 24. The Nature of Applied Science and Technology -- 25. The Technology-Science-Philosophy Triangle in Its Social Context -- 26. The Technologies in Philosophy --VIII. MORAL PHILOSOPHY -- 27. A New Look at Moral Realism -- 28. Rights Imply Duties --IX. SOCIAL AND POLITICAL PHILOSOPHY -- 29. Morality Is the Basis of Legal and Political Legitimacy -- 30. Technoholodemocracy: An Alternative to -- Capitalism and Socialism -- Bibliography -- Index of Names -- Index of Subjects. (shrink)

In this 1974 book a practising scientist and gifted expositor sets forth an exciting point of view on the nature of science and how it works.

There are two possible realist defense strategies against the pessimistic meta-induction and Laudan’s meta-modus tollens: the selective strategy, claiming that discarded theories are partially true, and the discontinuity strategy, denying that pessimism about past theories can be extended to current ones. A radical version of discontinuity realism is proposed by Gerald Doppelt: rather than discriminating between true and false components within theories, he holds that superseded theories cannot be shown to be even partially true, while present best theories are demonstrably (...) completely true. I argue that this position, running counter both the cumulativity of science and fallibilism, is untenable; it cannot account for the success of past theories, nor for the failures of current theories, and rather than shutting the door to the pessimistic historical objections it opens it wide. The best strategy, instead, joins the selective idea there was both some truth and some falsity in discarded theories, like in current ones, with the moderate discontinuity idea that the truth rate in present best theories is much greater than in past ones. (shrink)

The purpose of this book is to give a coherent account of the different perspectives on science and technology that are normally studied under various disciplinary heads such as philosophy of science, sociology of science and science policy. It is intended for students embarking on courses in these subjects and assumes no special knowledge of any science. It is written in a direct and simple style, and technical language is introduced very sparingly. As various perspectives are sketched out in this (...) book, the reader moves towards a consistent conception of contemporary science as a rapidly changing social institution that has already grown out of its traditional forms and plays a central role in society at large. It will appeal to students in a wide range of scientific disciplines and complement well Professor Ziman's earlier books. (shrink)

I want to combine two hitherto largely independent research projects, scientific understanding and mechanistic explanations. Understanding is not only achieved by answering why-questions, that is, by providing scientific explanations, but also by answering what-questions, that is, by providing what I call scientific descriptions. Based on this distinction, I develop three forms of understanding: understanding-what, understanding-why, and understanding-how. I argue that understanding-how is a particularly deep form of understanding, because it is based on mechanistic explanations, which answer why something happens in (...) virtue of what it is made of. I apply the three forms of understanding to two case studies: first, to the historical development of thermodynamics and, second, to the differences between the Clausius and the Boltzmann entropy in explaining thermodynamic processes. (shrink)

The ontological models framework distinguishes ψ-ontic from ψ-epistemic wave- functions. It is, in general, quite straightforward to categorize the wave-function of a certain quantum theory. Nevertheless, there has been a debate about the ontological status of the wave-function in the statistical interpretation of quantum mechanics: is it ψ-epistemic and incomplete or ψ-ontic and complete? I will argue that the wave- function in this interpretation is best regarded as ψ-ontic and incomplete.

Deployment Realism resists Laudan’s and Lyons’ objections to the “No Miracle Argument” by arguing that a hypothesis is most probably true when it is deployed essentially in a novel prediction. However, Lyons criticized Psillos’ criterion of essentiality, maintaining that Deployment Realism should be committed to all the actually deployed assumptions. But since many actually deployed assumptions proved false, he concludes that the No Miracle Argument and Deployment Realism fail. I reply that the essentiality condition is required by Occam’s razor. In (...) fact, there is a simpler formulation of essentiality which escapes Lyons’ criticisms and rescues the No Miracle Argument and Deployment Realism from their purported historical counterexamples: a hypothesis is essential when it has no proper parts (in Yablo’s sense) sufficient to derive the same prediction. Although essentiality so conceived cannot be detected prospectively, this is just natural, and it is not a problem but an advantage for Deployment Realism. (shrink)

What does it take to understand a phenomenon ideally, or to the highest conceivable extent? In this paper, we answer this question by arguing for five necessary conditions for ideal understanding: (i) representational accuracy, (ii) intelligibility, (iii) truth, (iv) reasonable endorsement, and (v) fitting. Even if one disagrees that there is some form of ideal understanding, these five conditions can be regarded as sufficient conditions for a particularly deep level of understanding. We then argue that grasping, novel predictions, and transparency (...) are not reasonable conditions for ideal understanding. (shrink)

Philosophers now seem to agree that frequentism is an untenable strategy to explain the meaning of probabilities. Nevertheless, I want to revive frequentism, and I will do so by grounding probabilities on typicality in the same way as the thermodynamic arrow of time can be grounded on typicality within statistical mechanics. This account, which I will call typicality frequentism, will evade the major criticisms raised against previous forms of frequentism. In this theory, probabilities arise within a physical theory from statistical (...) behavior of almost all initial conditions. The main advantage of typicality frequentism is that it shows which kinds of probabilities (that also have empirical relevance) can be derived from physics. Although one cannot recover all probability talk in this account, this is rather a virtue than a vice, because it shows which types of probabilities can in fact arise from physics and which types need to be explained in different ways, thereby opening the path for a pluralistic account of probabilities. (shrink)

Abstract We examine the construction of electromagnetism in its current form, and in an alternative form, from a point of view that combines a minimal realism with strict rational demands. We begin by discussing the requests of reason when constructing a theory and next, we follow the historical development as presented in the record of original publications, the underlying epistemology (often explained by the authors) and the mathematical constructions. The historical construction develops along socio-political disputes (mainly, the reunification of Germany (...) and the second industrial revolution), epistemic disputes (at least two demarcations of science in conflict) and several theories of electromagnetism. Such disputes resulted in the militant adoption of the ether by some, a position that expanded in parallel with the expansion of Prussia. This way of thinking was facilitated by the earlier adoption of a standpoint that required, as a condition for understanding, the use of physical hypothesis in the form of analogies; an attitude that is antithetic to Newton's “hypotheses non fingo”. While the material ether was finally abandoned, the epistemology survived in the form of “substantialism” and a metaphysical ether: the space. The militants of the ether attributed certainties regarding the ether to Faraday and Maxwell, when they only expressed doubts and curiosity. Thus, the official story is not the real history. This was achieved by the operation of detaching Maxwell's electromagnetism from its construction and introducing a new game of formulae and interpretations. Large and important parts of Maxwell work are today not known, as for example, the rules for the transformation of the electromagnetic potentials between moving systems. When experiments showed that all the theories based in the material ether were incorrect, a new interpretation was offered: Special Relativity (SR). At the end of the transformation period a pragmatic view of science, well adapted to the industrial society, had emerged, as well as a new protagonist: the theoretical physicist. The rival theory of delayed action at distance initiated under the influence of Gauss was forgotten in the midst of the intellectual warfare. The theory is indistinguishable in formulae from Maxwell's and its earlier versions are the departing point of Maxwell for the construction of his equations. We show in a mathematical appendix that such (relational) theory can incorporate Lorentz' contributions as well as Maxwell's transformations and C. Neumann's action, without resource to the ether. Demarcation criteria was further changed at the end of the period making room for habits and intuitions. When these intuited criteria are examined by critical reason (seeking for the fundaments) they can be sharpened with the use of the Non Arbitrariness Principle, which throws light over the arbitrariness in the construction of SR. Under a fully rational view SR is not acceptable, it requires to adopt a less demanding epistemology that detaches the concept from the conception, such as Einstein's own view in this respect, inherited from Hertz. In conclusion: we have shown in this relevant exercise how the reality we accept depends on earlier, irrational, decisions that are not offered for examination but rather are inherited from the culture. (shrink)

Chasing Reality deals with the controversies over the reality of the external world. Distinguished philosopher Mario Bunge offers an extended defence of realism, a critique of various forms of contemporary anti-realism, and a sketch of his own version of realism, namely hylorealism. Bunge examines the main varieties of antirealism - Berkeley's, Hume's, and Kant's; positivism, phenomenology, and constructivism - and argues that all of these in fact hinder scientific research. Bunge's realist contention is that genuine explanations in the sciences appeal (...) to causal laws and mechanisms that are not directly observable, rather than simply to empirical generalisations. Genuine science, in his view, is objective even when it deals with subjective phenomena such as feelings of fear. This work defends a realist view of universals, kinds, possibilities, and dispositions, while rejecting contemporary accounts of these that are couched in terms of modal logic and 'possible worlds.'. (shrink)