In standard quantum mechanics, a state vector \ may belong to infinitely many different orthogonal bases, as soon as the dimension N of the Hilbert space is at least three. On the other hand, a complete physical observable A is associated with a N-dimensional orthogonal basis of eigenvectors. In an idealized case, measuring A again and again will give repeatedly the same result, with the same eigenvalue. Let us call this repeatable result a modality \, and the corresponding eigenstate \. (...) A question is then: does \ give a complete description of \? The answer is obviously no, since \ does not specify the full observable A that allowed us to obtain \; hence the physical description given by \ is incomplete, as claimed by Einstein, Podolsky and Rosen in their famous article in 1935. Here we want to spell out this provocative statement, and in particular to answer the questions: if \ is an incomplete description of \, what does it describe? is it possible to obtain a complete description, maybe algebraic? Our conclusion is that the incompleteness of standard QM is due to its attempt to describe systems without contexts, whereas both are always required, even if they can be separated outside the measurement periods. (shrink)

We investigate the Peres–Horodecki positive partial transpose criterion in the context of conserved quantities and derive a condition of inseparability for a composite bipartite system depending only on the dimensions of its subsystems, which leads to a bi-linear entanglement witness for the two qubit system. A separability inequality using generalized Schrodinger–Robertson uncertainty relation taking suitable operators, has been derived, which proves to be stronger than the bi-linear entanglement witness operator. In the case of mixed density matrices, it identically distinguishes the (...) separable and non separable Werner states. (shrink)

Perhaps the hottest topic in the philosophy of chemistry is that of the relationship between chemistry and physics. The problem finds one of its main manifestations in the debate about the nature of molecular structure, given by the spatial arrangement of the nuclei in a molecule. The traditional strategy to address the problem is to consider chemical cases that challenge the definition of molecular structure in quantum–mechanical terms. Instead of taking that top-down strategy, in this paper we face the problem (...) of the reduction of molecular structure to quantum mechanics from a bottom-up perspective: our aim is to show how the theoretical peculiarities of quantum mechanics stand against the possibility of molecular structure, defined in terms of the spatial relations of the nuclei conceived as individual localized objects. We will argue that, according to the theory, quantum “particles” are not individuals that can be identified as different from others and that can be reidentified through time; therefore, they do not have the ontological stability necessary to maintain the relations that can lead to a spatially definite system with an identifiable shape. On the other hand, although quantum chemists use the resources supplied by quantum mechanics with successful results, this does no mean reduction: their “approximations” add certain assumptions that are not justified in the context of quantum mechanics or are even inconsistent with the very formal structure of the theory. (shrink)

We make use of natural induction to propose, following John Ju Sakurai, a generalization of Bell's inequality for two spin s=n/2(n=1,2,...) particle systems in a singlet state. We have found that for any finite integer or half-integer spin Bell's inequality is violated when the terms in the inequality are calculated from a quantum mechanical point of view. In the final expression for this inequality the two members therein are expressed in terms of a single parameter θ. Violation occurs for θ (...) in some interval of the form (α,π/2) where α parameter becomes closer and closer to π/2, as the spin grows, that is, the greater the spin number the size of the interval in which violation occurs diminishes to zero. Bell's inequality is a relationship among observables that discriminates between Einstein's locality principle and the non-local point of view of orthodox quantum mechanics. So our conclusion may also be stated by saying that for large spin numbers the non-local and local points of view agree. (shrink)

Contemporary debate over laws of nature centers around Humean supervenience, the thesis that everything supervenes on the distribution of non-nomic facts. The key ingredient of this thesis is the idea that nomic-like concepts—law, chance, causation, etc.—are expressible in terms of the regularities of non-nomic facts. Inherent to this idea is the tacit conviction that regularities, “constant conjunctions” of non-nomic facts do supervene on the distribution of non-nomic facts. This paper raises a challenge for this conviction. It will be pointed out (...) that the notion of regularity, understood as statistical correlation, has a necessary conceptual component not clearly identified before—I shall call this the “conjunctive relation” of the correlated events. On the other hand, it will be argued that there exists no unambiguous, non-circular way in which this relation could be determined. In this regard, the notion of correlation is similar to that of distant simultaneity where the necessary conceptual component is the one-way speed of light, whose value doesn’t seem to be determined by matters of facts. (shrink)

Most physics theories are deterministic, with the notable exception of quantum mechanics which, however, comes plagued by the so-called measurement problem. This state of affairs might well be due to the inability of standard mathematics to “speak” of indeterminism, its inability to present us a worldview in which new information is created as time passes. In such a case, scientific determinism would only be an illusion due to the timeless mathematical language scientists use. To investigate this possibility it is necessary (...) to develop an alternative mathematical language that is both powerful enough to allow scientists to compute predictions and compatible with indeterminism and the passage of time. We suggest that intuitionistic mathematics provides such a language and we illustrate it in simple terms. (shrink)

Propensities are presented as a generalization of classical determinism. They describe a physical reality intermediary between Laplacian determinism and pure randomness, such as in quantum mechanics. They are characterized by the fact that their values are determined by the collection of all actual properties. It is argued that they do not satisfy Kolmogorov axioms; other axioms are proposed.

Gerald Holton has famously described Einstein’s career as a philosophical “pilgrimage”. Starting on “the historic ground” of Machian positivism and phenomenalism, following the completion of general relativity in late 1915, Einstein’s philosophy endured (a) a speculative turn: physical theorizing appears as ultimately a “pure mathematical construction” guided by faith in the simplicity of nature and (b) a realistic turn: science is “nothing more than a refinement ”of the everyday belief in the existence of mind-independent physical reality. Nevertheless, Einstein’s mathematical constructivism (...) that supports his unified field theory program appears to be, at first sight, hardly compatible with the common sense realism with which he countered quantum theory. Thus, literature on Einstein’s philosophy of science has often struggled in finding the thread between ostensibly conflicting philosophical pronouncements. This paper supports the claim that Einstein’s dialog with Émile Meyerson from the mid 1920s till the early 1930s might be a neglected source to solve this riddle. According to Einstein, Meyerson shared (a) his belief in the independent existence of an external world and (b) his conviction that the latter can be grasped only by speculative means. Einstein could present his search for a unified field theory as a metaphysical-realistic program opposed to the positivistic-operationalist spirit of quantum mechanics. (shrink)

An analysis of the physical implications of abstractness reveals the reality of three interconnected modes of existence: abstract, virtual and concrete, corresponding in physics to information, energy and matter. This triple-aspect monism clarifies the ontological status of subatomic quantum particles. It also provides a non-spooky solution to the weirdness of quantum physics and a new outlook for the mind-body problem. The ontological implications are profound for both physics and philosophy.

Signal causality, the prohibition of superluminal information transmission, is the fundamental property shared by quantum measurement theory and relativity, and it is the key to understanding the connection between nonlocal measurement effects and elementary interactions. To prevent those effects from transmitting information between the generating and observing process, they must be induced by the kinds of entangling interactions that constitute measurements, as implied in the Projection Postulate. They must also be nondeterministic as reflected in the Born Probability Rule. The nondeterminism (...) of entanglement-generating processes explains why the relevant types of information cannot be instantiated in elementary systems, and why the sequencing of nonlocal effects is, in principle, unobservable. This perspective suggests a simple hypothesis about nonlocal transfers of amplitude during entangling interactions, which yields straightforward experimental consequences. (shrink)

The very formal structure of quantum mechanics implies the loss of individuality of physical systems and it requires to look at the Universe as an unbroken whole. The main reason for which, within such a theory, one must renounce to a clear identification of the parts and the whole is the superposition principle which stays at the basis of the theory. It implies, as well known, the phenomenon of entanglement which, in the most extreme case, entails that the constituents of (...) a composite system do not possess any objective property; only the system as a whole, when it is isolated, has some properties. Another source of difficulties derives from the symmetry requests that the theory imposes in the case of systems containing identical constituents. We discuss these points in detail and we outline recent proposals yielding a consistent solution to the problems arising from the entanglement between a microsystem and a macrosystem which unavoidably occurs in a measurement process. In particular we take into account the so called “collapse” theories which embody a mechanism forbidding, at an appropriate level, the persistence of superpositions and, as a consequence, lead, in general, to the emergence of precise individual properties for macroscopic systems. We then pass to a critical analysis of the difficulties related to the identity of the constituents. We stress that various misunderstandings characterize the treatment of this problem and we make fully clear how one has to deal with the very concept of entangled systems when identical constituents are involved. The ensuing picture should make clear to which extent one can still consistently ground the distinction between the parts and the whole in a genuinely quantum context. (shrink)

We reconsider the nonlocal aspects of quantum mechanics with special reference to the EPR argument. We first confine our considerations to the correlations between the outcomes of measurements on spatially distant constituents, without worrying about the measurement problem. We pay particular attention to the relativistic aspects of the problem. Our first conclusion is that, when developed along the lines we follow, the EPR inference that quantum correlations and locality together imply incompleteness, is appropriate. We then investigate whether the other common (...) conclusion from the EPR argument, i.e. that standard quantum theory implies a spooky action at a distance, is correct. We emphasize the crucial role played by the locality assumption and we discuss the use of counterfactuals in the ‘relativistic’ reformulation of the EPR argument. We show that the above conclusion is false if understood as saying that standard quantum theory exhibits, at least with reference to possessed elements of physical reality, some sort of parameter dependence. Thus, in a sense, the coexistence of quantum mechanics with relativity is even more peaceful than commonly thought. We then go through a similar analysis by taking explicitly into account the measurement process. We point out the difficulties which one meets when confronting reduction mechanisms with relativistic requirements. This leads us to recognize the necessity of reconsidering the criteria for attributing objective properties to individual physical systems. Our final conclusion is that, in principle, it is perfectly possible to build up theories leading to the objectification of macroscopic properties which do not imply any spooky action at a distance. (shrink)

In the paper we look into the epistemology of quantum theory. The starting point is the previously established mathematical ambiguity. The perspective of our study is the way that Schrödinger described Einstein’s idea of physics epistemology. Namely, physical theory is a map with flags. Each flag must, according to Einstein in Schrödinger’s representation, correspond to a physical reality and vice versa. With the ambiguity transformed to quantum-like operators we are able to mimic quantum theory. Therefore we have created little flags. (...) The question is raised whether nature itself is ambiguous. The created flags point at ambiguous nature. Or, nature is not ambiguous and the ambiguity can be repaired in mathematics. (shrink)

Summary Some case studies in elementary particle physics are presented in this work, that can be used for the critical appraisal of specific criteria which were proposed to account for the development of Heisenberg's work. It is attempted to define the philosophical problems associated with and emerging from the structures of theories, rather than analyse the philosophical aspects of concepts used in elementary particle physics. This necessitates the discussion of the relationship between theory and experiment, and the role of the (...) mathematical framework being used. The question of elementarity is studied in this connection. Popper's tetradic schema and his concept of world three are modified, and it is shown that the new schema can accommodate the development of certain research programs in a much more satisfactory manner. As a result of the systematic treatment of specific research programs, the principle of contextual re-interpretation is expanded by specifying the different kinds of interpretations at the various stages of development of theories. It is also shown that principles such as those of simplicity and beauty can be understood in terms of the mathematical structure of the theories, and their methodological importance is emphasized. (shrink)

For time-independent fields the Aharonov-Bohm effect has been obtained by idealizing the coordinate space as multiply-connected and using representations of its fundamental homotopy group to provide information on what is physically identified as the magnetic flux. With a time-dependent field, multiple-connectedness introduces the same degree of ambiguity; by taking into account electromagnetic fields induced by the time dependence, full physical behavior is again recovered once a representation is selected. The selection depends on a single arbitrary time (hence the so-called holonomies (...) are not unique), although no physical effects depend on the value of that particular time. These features can also be phrased in terms of the selection of self-adjoint extensions, thereby involving yet another question that has come up in this context, namely, boundary conditions for the wave function. (shrink)

The standard interpretation of quantum physics (QP) and some recent generalizations of this theory rest on the adoption of a rerificationist theory of truth and meaning, while most proposals for modifying and interpreting QP in a “realistic” way attribute an ontological status to theoretical physical entities (ontological realism). Both terms of this dichotomy are criticizable, and many quantum paradoxes can be attributed to it. We discuss a new viewpoint in this paper (semantic realism, or briefly SR), which applies both to (...) classical physics (CP) and to QP. and is characterized by the attempt of giving up verificationism without adopting ontological realism. As a first step, we construct a formalized observative language L endowed with a correspondence truth theory. Then, we state a set of axioms by means of L which hold both in CP and in QP. and construct a further language Lv which can express bothtestable andtheoretical properties of a given physical system. The concepts ofmeaning andtestability do not collapse in L and Le hence we can distinguish between semantic and pragmatic compatibility of physical properties and define the concepts of testability and conjoint testability of statements of L and Le. In this context a new metatheoretical principle (MGP) is stated, which limits the validity of empirical physical laws. By applying SR (in particular. MGP) to QP, one can interpret quantum logic as a theory of testability in QP, show that QP is semantically incomplete, and invalidate the widespread claim that contextuality is unavoidable in QP. Furthermore. SR introduces some changes in the conventional interpretation of ideal measurements and Heisenberg’s uncertainty principle. (shrink)

We prove that the general scheme for physical theories that we have called semantic realism(SR) in some previous papers copes successfully with a number of EPR-like paradoxes when applied to quantum physics (QP). In particular, we consider the old arguments by Furry and Bohm- Aharonov and show that they are not valid within a SR framework. Moreover, we consider the Bell-Kochen-Specker und the Bell theorems that should prove that QP is inherently contextual and nonlocal, respectively, and show that they can (...) be invalidated in the SR approach. This removes the seeming contradiction between the basic assumptions of SR and QP, and proves that some problematic features that are usually attributed to QP, us contextuality and nonlocality, occur because of the adoption of a verificationist position, from one side, and from an insufficient adherence to the operational principles that have inspired QP itself, from the other side. (shrink)

Nonobjectivity of physical properties enters physics with the standard interpretation of quantum mechanics (QM), and a number of paradoxes of this theory follow from it. It seems, however, based on sound physical arguments (double slit experiment, Heisenberg's principle, Bell–Kochen–Specker theorem, etc.), so that most physicists think that avoiding it is impossible. We discuss these arguments here and show that they can be criticized from a physical viewpoint. Our criticism proves that nonobjectivity must be considered an epistemological choice rather than an (...) unavoidable feature of QM, so that an objective interpretation of QM is not a priori impossible, which justifies our attempt at providing it in some previous papers. This interpretation is based on a classical language in which the language of the standard interpretation (Quantum Logic) is embedded as a subset of statements that are directly testable according to QM. (shrink)

One of the authors has recently propounded an SR model which shows, circumventing known no-go theorems, that an objective interpretation of quantum mechanics is possible. We consider here compound physical systems and show why the proofs of nonlocality of QM do not hold within the SR model, which is slightly simplified in this paper. We also discuss quantum measurement theory within this model, note that the objectification problem disappears since the measurement of any property simply reveals its unknown value, and (...) show that the projection postulate can be considered as an approximate law, valid FAPP. Finally, we provide an intuitive picture that justifies some unusual features of the SR model and proves its consistency. (shrink)

The old Bohr–Einstein debate about the completeness of quantum mechanics (QM) was held on an ontological ground. The completeness problem becomes more tractable, however, if it is preliminarily discussed from a semantic viewpoint. Indeed every physical theory adopts, explicitly or not, a truth theory for its observative language, in terms of which the notions of semantic objectivity and semantic completeness of the physical theory can be introduced and inquired. In particular, standard QM adopts a verificationist theory of truth that implies (...) its semantic nonobjectivity; moreover, we show in this paper that standard QM is semantically complete, which matches Bohr's thesis. On the other hand, one of the authors has provided a Semantic Realism (or SR) interpretation of QM that adopts a Tarskian theory of truth as correspondence for the observative language of QM (which was previously mantained to be impossible); according to this interpretation QM is semantically objective, yet incomplete, which matches EPR's thesis. Thus, standard QM and the SR interpretation of QM come to opposite conclusions. These can be reconciled within an integrationist perspective that interpretes non-Tarskian theories of truth as theories of metalinguistic concepts different from truth. (shrink)

It has been debated whether protective measurement implies the reality of the wave function. In this article, I present a new analysis of the relationship between protective measurements and the reality of the wave function. First, I briefly introduce protective measurements and the ontological models framework for them. Second, I give a simple proof of Hardy’s theorem in terms of protective measurements. Third, I analyse two suggested ψ -epistemic models of a protective measurement. It is shown that although these models (...) can explain the appearance of expectation values of observables in a single measurement, their predictions about the variance of the result of a non-ideal protective measurement are different from those of quantum mechanics. Finally, I argue that under an auxiliary finiteness assumption about the dynamics of the ontic state, protective measurement implies the reality of the wave function in the ontological models framework. (shrink)

Retrocausal quantum mechanics (RQM) provides a local causal explanation of Bell correlations. It is widely thought that RQM is consistent with special relativity. In this paper, I point out that this view is not wholly right. It is argued that RQM violates the Lorentz invariance of the temporal relation between cause and effect for certain spacelike separated events in Bell-type experiments.

The ontological model framework provides a rigorous approach to address the question of whether the quantum state is ontic or epistemic. When considering only conventional projective measurements, auxiliary assumptions are always needed to prove the reality of the quantum state in the framework. For example, the Pusey-Barrett-Rudolph theorem is based on an additional preparation independence assumption. In this paper, we give a new proof of psi-ontology in terms of protective measurements in the ontological model framework. The proof does not rely (...) on auxiliary assumptions, and also applies to deterministic theories such as the de Broglie-Bohm theory. In addition, we give a simpler argument for psi-ontology beyond the framework, which is based on protective measurements and a weaker criterion of reality. The argument may be also appealing for those people who favor an anti-realist view of quantum mechanics. (shrink)

The monistic worldview aims at a uniform description of nature based on scientific models. Quantum physical systems are mutually part of the other quantum physical systems. An aperture distributes the subsystems and the wave front in all possible ways. The system only takes one of the possible paths, as measurements show. Conclusion from Bell's theorem: Before the quantum physical measurement, there is no point-like location in the universe where all the information that explains the measurement is available. Distributed information is (...) possible. Movement of the particle and measuring process are deterministic. The oscillation between location uncertainty and momentum uncertainty leads photons to determine their own location at short intervals. The uncertainty principle focuses the systems. The fields of the surrounding matter influence the location of the new formation. The effect of all fields is based on a common mechanism. (shrink)

Constructivist epistemology posits that all truths are knowable. One might ask to what extent constructivism is compatible with naturalized epistemology and knowledge obtained from inference-making using successful scientific theories. If quantum theory correctly describes the structure of the physical world, and if quantum theoretic inferences about which measurement outcomes will be observed with unit probability count as knowledge, we demonstrate that constructivism cannot be upheld. Our derivation is compatible with both intuitionistic and quantum propositional logic. This result is implied by (...) the Frauchiger-Renner theorem, though it is of independent importance as well. (shrink)

Within the field of causal inference, it is desirable to learn the structure of causal relationships holding between a system of variables from the correlations that these variables exhibit; a sub-problem of which is to certify whether or not a given causal hypothesis is compatible with the observed correlations. A particularly challenging setting for assessing causal compatibility is in the presence of partial information; i.e. when some of the variables are hidden/latent. This paper introduces the possible worlds framework as a (...) method for deciding causal compatibility in this difficult setting. We define a graphical object called a possible worlds diagram, which compactly depicts the set of all possible observations. From this construction, we demonstrate explicitly, using several examples, how to prove causal incompatibility. In fact, we use these constructions to prove causal incompatibility where no other techniques have been able to. Moreover, we prove that the possible worlds framework can be adapted to provide a complete solution to the possibilistic causal compatibility problem. Even more, we also discuss how to exploit graphical symmetries and cross-world consistency constraints in order to implement a hierarchy of necessary compatibility tests that we prove converges to sufficiency. (shrink)

A comprehensive formal system is developed that amalgamates the operational and the realistic approaches to quantum mechanics. In this formalism, for example, a sharp distinction is made between events, operational propositions, and the properties of physical systems.

It has become apparent that the debate between scientific realists and constructive empiricists has come to a stalemate. Neither view can reasonably claim to be the most rational philosophy of science, exclusively capable of making sense of all scientific activities. On one prominent analysis of the situation, whether we accept a realist or an anti-realist account of science actually seems to depend on which values we antecedently accept, rather than our commitment to “rationality” per se. Accordingly, several philosophers have attempted (...) to argue in favour of scientific realism or constructive empiricism by showing that one set of values is exclusively best, for anyone and everyone, and that the downstream choice of the philosophy of science which best serves those values is therefore best, for anyone and everyone. These efforts, however, seem to have failed. In response, I suggest that philosophers of science should suspend the effort to determine which philosophy of science is best for everyone, and instead begin investigating which philosophy of science is best for specific people, with specific values, in specific contexts. I illustrate how this might be done by briefly sketching a single case study from the history of science, which seems to show that different philosophies of science are better at motivating different forms of scientific practice. (shrink)

Can quantum theory provide examples of metaphysical indeterminacy, indeterminacy that obtains in the world itself, independently of how one represents the world in language or thought? We provide a positive answer assuming just one constraint of orthodox quantum theory: the eigenstate-eigenvalue link. Our account adds a modal condition to preclude spurious indeterminacy in the presence of superselection sectors. No other extant account of metaphysical indeterminacy in quantum theory meets these demands.

A level of adequacy of a given model with physical world represents an important element of physics. In an “ideal” model each element in the model would correspond exactly to one element in the physical world. In such a model each element would have a direct epistemological correlation with exactly one element of the physical world. Such a model would become a perfect picture of the physical world. The possibility of misinterpretation, in a sense that one searches for physical existence (...) of purely theoretically predicted elements of the model, would be excluded. In order to develop such a model we apply bijective function of set theory. Bijective function applied on time research shows model of space–time has no direct epistemological correlation in physical reality. Time is duration of changes which run in space. Duration does not run in time, duration is time. (shrink)

This paper examines the efficiency problem involved in experimental tests of so-called “local” hidden variables. It separates the phenomenological locality at issue in the Bell case from Einstein's different conception of locality, and shows how phenomenological locality also differs from the factorizability needed to derive the Bell inequalities in the stochastic case. It then pursues the question of whether factorizable, local models (or, equivalently, deterministic ones) exist for the experiments designed to test the Bell inequalities, thus rendering the experimental argument (...) against them incomplete. This leads to an investigation of the so-called “prism models” and to new inequalities for a significant class of such models, inequalities that are testable even at the low efficiencies of the photon correlation experiments. (shrink)

A violation of Bell’s inequalities is generally considered to be the Holy Grail of experimental proof that a specific natural phenomenon cannot be explained in a classical framework and is based on a non-boolean structure of predications. Generalized quantum theory allows for such non-boolean predications. We formulate temporal Bell’s inequalities for cognitive two-state systems and indicate how these inequalities can be tested. This will introduce the notion of temporally non-local measurements. The Necker-Zeno model for bistable perception predicts a violation of (...) these temporal Bell’s inequalities. (shrink)

This paper pursues the question, To what extent does the propensity approach to probability contribute to plausible solutions to various anomalies which occur in quantum mechanics? The position I shall defend is that of the three interpretations — the frequency, the subjective, and the propensity — only the third accommodates the possibility, in principle, of providing a realistic interpretation of ontic indeterminism. If these considerations are correct, then they lend support to Popper's contention that the propensity construction tends to remove (...) (at least some of) the mystery from quantum phenomena. (shrink)

It has been traditionally considered that Quantum Mechanics has two conceptual kinds of problems, namely, those related with local-realism and the so-called measurement problem. That is, the uniqueness of the result when we make a measurement. With the development of what is called generically Quantum Information Theory, a new form of the Copenhagen interpretation of the formalism has taken shape.(1) In this paper, we will analyse if this information interpretation is able to clarify these old problems. Although this interpretation seems (...) to be the most promising approach we have, we have reached the conclusion that the answer cannot be given in a positive and clear way yet. (shrink)

In a previous essay we demonstrated that quantum mechanical formalism is incompatible with some necessary principles of the mechanism conception still dominant in the physicist’s community. In this paper we show, based on recent empirical evidence in quantum physics, the inevitability of abandoning the old mechanism conception and to construct a new one in which physical reality is seen as a representation which refers to relations established through operations made by us in a world that we are determining. This change (...) is profound and radical, with immediate consequences on both Ontology and Epistemology. This work is our contribution to try to make more concrete how this new conception of the world might be. (shrink)

The traditional “realist” conception of physics, according to which human concepts, laws and theories can grasp the essence of a reality in our absence , seems incompatible with quantum formalism and it most fruitful interpretation. The proof rests on the violation by quantum mechanical formalism of some fundamental principles of the classical ontology. We discuss if the conception behind Einstein’s idea of a reality in our absence, could be still maintained and at which price. We conclude that quantum mechanical formalism (...) is not formulated on those terms, leaving for a separated paper the discussion about the terms in which it could be formulated and the onto-epistemological implications it might have. (shrink)