The problem of properties in quantum mechanics

The properties of classical and quantum systems are characterized by different algebraic structures. We know that the properties of a quantum mechanical system form a partial Boolean algebra not embeddable into a Boolean algebra, and so cannot all be co-determinate. We also know that maximal Boolean subalgebras of properties can be (separately) co-determinate. Are there larger subsets of properties that can be co-determinate without contradiction? Following an analysis of Bohrs response to the Einstein-Podolsky-Rosen objection to the complementarity interpretation of quantum mechanics, a principled argument is developed justifying the selection of particular subsets of properties as co-determinate for a quantum system in particular physical contexts. These subsets are generated by sets of maximal Boolean subalgebras, defined in each case by the relation between the quantum state and a measurement (possibly, but not necessarily, the measurement in terms of which we seek to establish whether or not a particular property of the system in question obtains). If we are required to interpret quantum mechanics in this way, then predication for quantum systems is quite unlike the corresponding notion for classical systems.     

The exploitation of Gestalt principles by magicians

Magicians exploit a host of psychological principles in deceiving their audiences. Psychologists have recently attempted to pinpoint the most common psychological tendencies exploited by magicians. This paper highlights two co-occurring principles that appear to be the basis for many popular magic tricks: accidental alignment and good continuation.     

Gestalt theory reconfigured: Max Wertheimer's anticipation of recent developments in visual neuroscience

In the 1920s Max Wertheimer enunciated a credo of Gestalt theory: the properties of any of the parts are governed by the structural laws of the whole. Intense efforts at the time to discover these laws had only very limited success. Psychology was in the grips of the Fechnerian tradition to seek exact relationships between the material and the mental and, because the Gestalt movement could not deliver these, it never attained a major standing among students of perception. However, as neurophysiological research into cortical processing of visual stimuli progresses the need for organizing principles is increasingly making itself felt. Concepts like contour salience and figure segregation, once the province of Gestalt psychology, are now taking on renewed significance as investigators combine neural modeling and psychophysical approaches with electrophysiological ones to characterize neural mechanisms of cognition. But it would be perilous not to take heed of some of the lessons that the history of the Gestalt movement teaches.     

The classical limit of quantum theory

Both physicists and philosophers claim that quantum mechanics reduces to classical mechanics as 0, that classical mechanics is a limiting case of quantum mechanics. If so, several formal and non-formal conditions must be satisfied. These conditions are satisfied in a reduction using the Wigner transformation to map quantum mechanics onto the classical phase plane. This reduction does not, however, assist in providing an adequate metaphysical interpretation of quantum theory.Earlier versions of this essay received helpful criticism from Bruce Knight, Clark Glymour, and Donald Martin.     

On the mind/body problem: The theory of essence

The classical mind/body problem can be approached empirically, using instances of the near-death experience (NDE) as experimental data. The monistic viewpoint, that the mind is the functioning of the brain, finds little support in the NDE data, while dualism, mind and body as separate entities, is consistent with NDE research to date. Comparison of the details of the NDE with predictions from theoretical cosmology shows strong similarities between the two and further strengthens the case for dualism. A theory of human nature is proposed that incorporates these similarities.J. Kenneth Arnette, Ph.D. received a doctorate in Physical Chemistry from Florida State University     

Spatial learning based on the shape of the environment is influenced by properties of the objects forming the shape

In 3 experiments rats had to find a submerged platform that was located in a corner of a kite-shaped pool. The color of the walls creating this corner provided an additional cue for finding the platform in the shape + color condition but not the shape-only condition. During tests in a pool with walls of a uniform color but no platform, more time was spent in the corner where the platform was originally located after training in the shape + color than in the shape-only condition. The results challenge theories that assume either that learning about the shape of the environment takes place in a dedicated module or that cues compete for the control they acquire over behavior.     

The problem of gender in family therapy theory

The field of family therapy is now a continuous process like a car cruising on automatic control with the driver comfortably in the lotus position. Family therapy theory rests on normative concepts of the traditional family and idealized conceptions of family relationships. Inequalities in the family associated with gender have been regarded as of little importance to the development of macro theory in the field. The two most influential therapeutic models, psychodynamic and systemic approaches, are each marked by gender bias. The alpha prejudice of psychodynamic theories exaggerates gender differences; the beta prejudice of systemic approaches ignores them. The construction of gender role concepts has led to a false dichotomy, whether supported by traditionalists or feminists. On close examination, gender role ideals turn out to be simplifications and caricatures. The uncritical use of gender role concepts supports power differences between men and women and ignores the complexities and commonalities of human experience. The failure of family therapy theory to deal with gender issues needs to be addressed if a theory that is not just "more of the same" is to be developed.     

The problem of redundancy in movement control: The adaptive model theory approach

Summary The problem of redundancy in movement control is encountered when one attempts to answer the question: How does the central nervous system (CNS) determine the pattern of neural activity required in some 5,000,000 descending motor fibres to control only 100–150 biomechanical degrees of freedom of movement? Mathematically this is equivalent to solving a set of simultaneous equations with many more unknowns than equations. This system of equations is redundant because it has an infinite number of possible solutions. The problem is solved by the neuronal circuitry hypothesized in Adaptive Model Theory (AMT). According to AMT, the CNS includes neuronal circuitry able to compute and maintain adaptively the accuracy of internal models of the reciprocal multivariable relationships between outgoing motor commands and their resulting sensory consequences. To identify these input-output relationships by means of regression analysis, correlations between the input signals have to be taken into account. For example, if the inputs are perfectly correlated, the model reduces to a virtual one-input system. In general, the number of inputs modelled equals the number of degrees of freedom encoded by the signals; that is, the number of independently varying (orthogonal) signals. The adaptive modelling circuitry proposed in AMT automatically tunes itself to extract independently varying sensory and motor signals before computing the dynamic relationships between them. Inverse models are employed during response execution to translate movements preplanned as desired trajectories of these high-level sensory-feature signals into appropriately co-ordinated motor commands to send to the muscles. Since movement is preplanned in terms of a number of orthogonalized sensory-feature signals equal to the number of degrees of freedom in the desired response, the problem of redundancy is solved and the correlation or co-ordination between motor-command signals is automatically introduced by the adaptive models.     

Avoiding the problem state bottleneck by strategic use of the environment

We investigated whether environmental support can be used to circumvent the problem state bottleneck in human multitasking. Previously, it was shown that people can only maintain a single chunk of information in their problem state resource, the central part of working memory. Consequently, when the problem state resource was required by multiple tasks concurrently, performance decreased. This phenomenon was termed the problem state bottleneck. To investigate whether the environment can be used to circumvent this bottleneck, we conducted an experiment with two main conditions. In the No-Support condition we replicated an earlier experiment that indicated the existence of the problem state bottleneck. In the Support condition we presented external cues, reducing the load on the problem state resource. To support the results of the experiment we present a computational cognitive model. The experiment and model indicated that the problem state bottleneck can be avoided by using external cues. However, subjects only used external cues when this led to faster behavior. These results were interpreted in the light of the Soft Constraints Hypothesis, which states that humans always follow the fastest strategy possible, as opposed to the most accurate strategy.     

The Power of the Immediate Moment in Gestalt Therapy

This article discusses the gestalt therapy concept of the paradoxical theory of change and a method combining a dialogic relationship with active phenomenological focusing and experimenting. Fundamental change results from self-acceptance and not attempts to change based on self-rejection. This is supported by the characteristics of dialogic contact: inclusion, confirmation, authentic presence, and a commitment to what emerges between therapist and patient. The patient is taught how to be aware, including awareness of the awareness process, facilitating autonomous use of the method by the patient. Suggestions and cautions for practice are discussed. My thanks to Lynne Jacobs for help in writing this article