We propose a technical reformulation of the measurement problem of quantum mechanics, which is based on the postulate that the final state of a measurement is classical; this accords with experimental practice as well as with Bohr’s views. Unlike the usual formulation (in which the post-measurement state is a unit vector in Hilbert space), our version actually opens the possibility of admitting a purely technical solution within the confines of conventional quantum theory (as opposed to solutions that either modify this (...) theory, or introduce unusual and controversial interpretative rules and/or ontologies).To that effect, we recall a remarkable phenomenon in the theory of Schrödinger operators (discovered in 1981 by Jona-Lasinio, Martinelli, and Scoppola), according to which the ground state of a symmetric double-well Hamiltonian (which is paradigmatically of Schrödinger’s Cat type) becomes exponentially sensitive to tiny perturbations of the potential as ħ→0. We show that this instability emerges also from the textbook wkb approximation, extend it to time-dependent perturbations, and study the dynamical transition from the ground state of the double well to the perturbed ground state (in which the cat is typically either dead or alive, depending on the details of the perturbation).Numerical simulations show that adiabatically arising perturbations may (quite literally) cause the collapse of the wave-function in the classical limit. Thus, at least in the context of a simple mathematical model, we combine the technical and conceptual virtues of decoherence (which fails to solve the measurement problem but launches the key idea that perturbations may come from the environment) with those of dynamical collapse models à la grw (which do solve the measurement problem but are ad hoc), without sharing their drawbacks: single measurement outcomes are obtained (instead of merely diagonal reduced density matrices), and no modification of quantum mechanics is needed. (shrink)

A startling amount of intelligent activity can be controlled without reasoning or thought. By tuning the perceptual system to task relevant properties a creature can cope with relatively sophisticated environments without concepts. There is a limit, however, to how far a creature without concepts can go. Rod Brooks, like many ecologically oriented scientists, argues that the vast majority of intelligent behaviour is concept-free. To evaluate this position I consider what special benefits accrue to concept-using creatures. Concepts are either necessary for (...) certain types of perception, learning, and control, or they make those processes computationally simpler. Once a creature has concepts its capacities are vastly multiplied. (shrink)

Kenny’s main subject is the interrelationship of what we know as Aristotle’s Nicomachean Ethics and his Eudemian Ethics. His first and crucial aim is to show that the "common books," EN 5-7 = EE 4-6, belong with the EE rather than with the EN, where they are placed by all editions and translations. On the basis of this conclusion, he goes on to argue that there is no reason to accept the now-current view that the EN was written after the (...) EE rather than before it, and that once we accustom ourselves to thinking of the common books as part of the EE, we may well slough off the habit of centuries, and come to regard the EE as the authoritative and best Aristotelian treatise on ethics. (shrink)

The author states in his preface that he has not undertaken a history of aesthetic thought during the French Enlightenment, nor an intellectual history of French aesthetics, nor a synthesis of eighteenth-century French thought on aesthetics, nor a history of eighteenth-century French art. What he has attempted to do is to outline doctrines of French aesthetic thought during the eighteenth century. The term doctrine is perhaps not too strong here because some of these writers were rather doctrinaire in their approach. (...) Following an outline of their respective positions, the author then subjects their works to a logical analysis. More than two-thirds of the authors cited are relatively unknown: André, d'Argens, Batteux, Bonnet, Briseux, Chaussard, Crousaz, Mme. Dacier, Estère, de Jaucourt, de La Motte, di Marcenay de Ghuy, de Piles, Rollin, Taillason, Trublet. One should not be surprised to learn that few of these were professional philosophers. Others cited by Coleman are well-known eighteenth-century figures: d'Alembert, Condillac, Diderot, Dubos, Montesquieu and St. Evremond. The author explains that he undertook the book in order to fill a gap in the literature on the subject. It is an excellent beginning and the style in which it is written is often as witty and elegant as that of many of the authors he considers.—P. N. (shrink)