Along with exploring some of the necessary conditions for the chemistry of our world given what we know about quantum mechanics, I will also discuss a different reductionist challenge than is usually considered in debates on the relationship of chemistry to physics. Contrary to popular belief, classical physics does not have a reductive relationship to quantum mechanics and some of the reasons why reduction fails between classical and quantum physics are the same as for why reduction fails between chemistry and (...) quantum physics. However, a neoreductionist can accept that classical physics has some amount of autonomy from quantum mechanics, but still try to maintain that classical+quantum physics taken as a whole reduces chemistry to physics. I will explore some of the obstacles lying in the neoreductionist’s path with respect to quantum chemistry and thereby hope to shed more light on the conditions necessary for the chemistry of our world. (shrink)

The causal argument for physicalism is anayzed and it's key premise--the causal closure of physics--is found wanting. Therefore, a hidden premise must be added to the argument to gain its conclusion, but the hidden premise is indistinguishable from the conclusion of the causal argument. Therefore, it begs the question on physicalism.

The "usual story" regarding molecular chemistry is that it is roughly an application of quantum mechanics. That is to say, quantum mechanics supplies everything necessary and sufficient, both ontologically and epistemologically, to reduce molecular chemistry to quantum mechanics. This is a reductive story, to be sure, but a key explanatory element of molecular chemistry, namely molecular structure, is absent from the quantum realm. On the other hand, typical characterizations of emergence, such as the unpredictability or inexplicability of molecular structure based (...) on quantum mechanics, do not characterize the relationship between molecular chemistry and quantum mechanics well either. A different scheme for characterizing reduction and emergence is proposed that accommodates the relationship between quantum mechanics and molecular chemistry and some initial objections to the scheme are considered. (shrink)

The role of contingent contexts in formulating relations between properties of systems at different descriptive levels is addressed. Based on the distinction between necessary and sufficient conditions for interlevel relations, a comprehensive classification of such relations is proposed, providing a transparent conceptual framework for discussing particular versions of reduction, emergence, and supervenience. One of these versions, contextual emergence, is demonstrated using two physical examples: molecular structure and chirality, and thermal equilibrium and temperature. The concept of stability is emphasized as a (...) basic guiding principle of contextual property emergence. (shrink)

Quantum systems have a holistic structure, which implies that they cannot be divided into parts. In order tocreate (sub)objects like individual substances, molecules, nuclei, etc., in a universal whole, the Einstein-Podolsky-Rosen correlations between all the subentities, e.g. all the molecules in a substance, must be suppressed by perceptual and mental processes.Here the particular problems ofGestalt (shape)perception are compared with the attempts toattribute a shape to a quantum mechanical system like a molecule. Gestalt perception and quantum mechanics turn out (on an (...) informal level) to show similar features and problems: holistic aspects, creation of objects, dressing procedures, influence of the observer, classical quantities and structures. The attribute classical of a property or structure means thatholistic correlations to any other quantity do not exist or that these correlations are considered as irrelevant and therefore eliminated (either deliberately and by declaration or in a mental process that is not under rational control). An example of animposed classical structure is the nuclear frame of a molecule. Candidates for classical properties that arenot imposed by the observer could be the charge of a particle or the handedness of a molecule. It is argued here that at least part of a molecule's shape can begenerated automatically by the environment. A molecular shape of this sort arises in addition to Lamb shift-type energy corrections. (shrink)

This book explores whether physics points to a reductive or an emergent structure of the world and proposes a physics-motivated conception of emergence that leaves behind many of the problematic intuitions shaping the philosophical conceptions. Examining several detailed case studies reveals results that point to stability conditions playing a crucial though underappreciated role in the physics of emergence. This contextual emergence has thought-provoking consequences for physics and beyond.

Four current accounts of theory reduction are presented, first informally and then formally: (1) an account of direct theory reduction that is based on the contributions of Nagel, Woodger, and Quine, (2) an indirect reduction paradigm due to Kemeny and Oppenheim, (3) an "isomorphic model" schema traceable to Suppes, and (4) a theory of reduction that is based on the work of Popper, Feyerabend, and Kuhn. Reference is made, in an attempt to choose between these schemas, to the explanation of (...) physical optics by Maxwell's electromagnetic theory, and to the revisions of genetics necessitated by partial biochemical reductions of genetics. A more general reduction schema is proposed which: (1) yields as special cases the four reduction paradigms considered above, (2) seems to be in better accord with both the canons of logic and actual scientific practice, and (3) clarifies the problems of meaning variance and ontological reduction. (shrink)

By questioning the validity of some of our basic concepts, such as space, object, and causality, quantum physics contributes quite decisively to the dramatic changes now taking place in our world picture. Veiled Reality provides a detailed view of the reasons why such a questioning arises, a survey of the corresponding conceptual and theoretical problems, and a comprehensive, up-to-date account, useful to scientists and epistemologists alike, of the various ways present-day physicists tackle these problems.The book deals with the E.P.R. reality (...) criterion, local causality, and quantum measurement including relativistic quantum collapse, decoherence theories, consistent histories approaches, and ontologically interpretable theories. Questions bearing on the connection between counterfactuality and realism, intersubjective agreement, and limits of the bearing of the verbs “to have” and “to be,” follow naturally from the analysis and are thoroughly examined. Finally, distinguishing between empirical reality and a veiled independent reality whose only knowable features are structural yields a clue to a plausible interpretation of current physics.Accessible to readers with only very elementary background in modern physics, Veiled Reality offers nonspecialists, including students in physics and philosophy, easy access to basic problems in the foundation of physics. (shrink)

The emergence of mental states from neural states by partitioning the neural phase space is analyzed in terms of symbolic dynamics. Well-defined mental states provide contexts inducing a criterion of structural stability for the neurodynamics that can be implemented by particular partitions. This leads to distinguished subshifts of finite type that are either cyclic or irreducible. Cyclic shifts correspond to asymptotically stable fixed points or limit tori whereas irreducible shifts are obtained from generating partitions of mixing hyperbolic systems. These stability (...) criteria are applied to the discussion of neural correlates of consiousness, to the definition of macroscopic neural states, and to aspects of the symbol grounding problem. In particular, it is shown that compatible mental descriptions, topologically equivalent to the neurodynamical description, emerge if the partition of the neural phase space is generating. If this is not the case, mental descriptions are incompatible or complementary. Consequences of this result for an integration or unification of cognitive science or psychology, respectively, will be indicated. (shrink)

The context of an operational description is given by the distinction between what we consider as relevant and what as irrelevant for a particular experiment or observation. A rigorous description of a context in terms of a mathematically formulated context-independent fundamental theory is possible by the restriction of the domain of the basic theory and the introduction of a new coarser topology. Such a new topology is never given by first principles, but depends in a crucial way on the abstractions (...) made by the cognitive apparatus or the pattern recognition devices used by the experimentalist. A consistent mathematical formulation of a higher-level theory requires the closure of the restriction of the basic theory in the new contextual topology. The validity domain of the so constructed higher-level theory intersects nontrivially with the validity domain of the basic theory: neither domain is contained in the other. Therefore, higher-level theories cannot be totally ordered and theory reduction is not transitive. The emergence of qualitatively new properties is a necessary consequence of such a formulation of theory reduction (which does not correspond to the traditional one). Emergent properties are not manifest on the level of the basic theory, but they can be derived rigorously by imposing new, contextually selected topologies upon context-independent first principles. Most intertheoretical relations are mathematically describable as singular asymptotic expansions which do not converge in the topology of the primary theory, or by choosing one of the infinitely many possible, physically inequivalent representations of the primary theory (Gelfand–Naimark–Segal-construction of algebraic quantum mechanics). As examples we discuss the emergence of shadows, inductors, capacitors and resistors from Maxwell’s electrodynamics, the emergence of order parameters in statistical mechanics, the emergence of mass as a classical observable in Galilei-relativistic theories, the emergence of the shape of molecules in quantum mechanics, the emergence of temperature and other classical observables in algebraic quantum mechanics. (shrink)

Complexity–nonlinear dynamics for my purposes in this essay–is rich with metaphysical and epistemological implications but is only recently receiving sustained philosophical analysis. I will explore some of the subtleties of causation and constraint in Rayleigh-Bénard convection as an example of a complex phenomenon, and extract some lessons for further philosophical reflection on top-down constraint and causation particularly with respect to causal foundationalism.

The endo/exo-dichotomy in the domain of the material world is analyzed from the standpoint of old-fashioned Cartesian dualism. The holistic structure of the quantum world enforces a Platonic view for the universally valid laws governing matter. In contrast to the structural simplicity of non-operational quantum endophysics, the empirical reality and experiments belong to quantum exophysics. In algebraic quantum mechanics, the transition from quantum endophysics to quantum exophysics is mathematically welldefined. The exophysical richness and variety of the concrete and particular emerges (...) by imposing a new, contextually selected topology into fundamental endophysics. In the Cartesian world view, the inverse problem, however, is ill-posed. Though the endophysical realm can be grasped by human reason, endophysics cannot be set up from sense data and experiments without recourse to primordial images. (shrink)