Like every major new technology, genetic engineering is affecting the hopes and fears of many people. The risks involved are perceived differently by different groups. One group regards genetic engineering as a simple extension of older techniques with no special risks, e.g. traditional breeding. This conservative denial of special risks is confronted with a different kind of conservatism from a group which, in the name of the preservation of nature, opposes any kind of genetic engineering. A third group, rooted in (...) the liberal tradition, is prepared to accept the risks of genetic engineering as long as they are outweighed by prospective benefits. The liberal as well as the two conservative approaches, however, face serious difficulties in trying to develop a sound ethical argument concerning genetic engineering. In order to avoid these difficulties, an ethical approach focused on paradigmatic examples of good and evil is proposed. Such examples constitute rules of moral description, much as standards of measurement constitute rules of physical description. These rules are elaborated and interpreted in processes of social learning. In the present state of development of genetic engineering, such social learning requires appropriate institutional procedures. (shrink)

The first classification of general types of transition between phases of matter, introduced by Paul Ehrenfest in 1933, lies at a crossroads in the thermodynamical study of critical phenomena. It arose following the discovery in 1932 of a suprising new phase transition in liquid helium, the “lambda transition,” when W. H. Keesom and coworkers in Leiden, Holland observed a λhaped “jump” discontinuity in the curve giving the temperature dependence of the specific heat of helium at a critical value. This apparent (...) jump led Ehrenfest to introduce a classification of phase transitions on the basis of jumps in derivatives of the free energy function. This classification was immediately applied by A.J. Rutgers to the study of the transition from the normal to superconducting state in metals. Eduard Justi and Max von Laue soon questioned the possibility of its class of “second-order phase transitions” -- of which the “lambda transition was believed to be the arche type -- but C.J. Gorter and H.B.G. Casimir used an “order parameter to demonstrate their existence in superconductors. As a crossroads of study, the Ehrenfest classification was forced to undergo a slow, adaptive evolution during subsequent decades. During the 1940s the classification was increasingly used in discussions of liquid-gas, order-disorder, paramagnetic-ferromagnetic and normal-super-conducting phase transitions. Already in 1944 however, Lars Onsagers solution of the Ising model for two-dimensional magnets was seen to possess a derivative with a logarithmic divergence rather than a jump as the critical point was approached. In the 1950s, experiments further revealed the lambda transition in helium to exhibit similar behavior. Rather than being a prime example of an Ehrenfest phase transition, the lambda transition was seen to lie outside the Ehrenfest classification. The Ehrenfest scheme was then extended to include such singularities, most notably by A. Brain Pippard in 1957, with widespread acceptance. During the 1960s these logarithmic infinities were the focus of the investigation of “scaling” by Leo Kadanoff, B. Widom and others. By the 1970s, a radically simplified binary classification of phase transitions into “first-order” and “continuous” transitions was increasingly adopted. (shrink)

A case is made for supposing that the total probability accounted for in a decision analysis is less than unity. This is done by constructing a measure on the set of all codes for computable functions in such a way that the measure of every effectively accountable subset is bounded by a number <1. The consistency of these measures with the Savage axioms for rational preference is established. Implications for applied decision theory are outlined.

The current research investigates a combination of two instructional approaches, tutored problem solving and worked examples. Tutored problem solving with automated tutors has proven to be an effective instructional method. Worked‐out examples have been shown to be an effective complement to untutored problem solving, but it is largely unknown whether they are an effective complement to tutored problem solving. Further, while computer‐based learning environments offer the possibility of adaptively transitioning from examples to problems while tailoring to an individual learner, the (...) effectiveness of such machine‐adapted example fading is largely unstudied. To address these research questions, one lab and one classroom experiment were conducted. Both studies compared a standard Cognitive Tutor with two example‐enhanced Cognitive Tutors, in which the fading of worked‐out examples occurred either in a fixed way or adaptively. Results indicate that the adaptive fading of worked‐out examples leads to higher transfer performance on delayed posttests than the other two methods. (shrink)

The debate about positive and negative claims of conscience is, in large part, about ethical consistency. In this commentary I argue that there can be differences between conscientious provision of treatment and conscientious nonprovision of treatment that are ethically relevant. However, in many cases, including those described in this commentary, there is not sufficient ethical reason to treat them differently. This means that asymmetrical conscientious objection policies are potentially unjustified.

I intend to defend the following as a necessary condition of a belief S being epistemically justified for a subject:Awareness Requirement: S is justified in believing that P only if i) there is something, X, that contributes to the justification of B; and ii) S is aware of X.This will be shown through drawing attention to our considered judgments about cases. That will then lay the groundwork for giving an account of the nature of this awareness in the second half (...) of this paper. In doing so I will examine and respond to an argument against the awareness requirement that we might call Bergmann‟s Dilemma. My solution invokes what I call “non-doxastic strong awareness” in a way that avoids the regresses that Bergmann advances. (shrink)

In this commentary I assess the possible harms to a fetus with trisomy 18 of continued life. I argue that, although there is good reason to avoid subjecting infants to major surgery and prolonged intensive care where there is little chance of benefit, doctors should support and engage honestly with parents who decide to continue their pregnancies. We should ensure that infants with trisomy 18 have access to high quality palliative care.

In this essay I contrast Freud’s account of mourning in Mourning and Melancholia to that of Merleau-Ponty in Phenomenology of Perception. In suggesting a somatic as well as a psychic response, Merleau-Ponty, I argue, more accurately accounts for the ways in which we experience loss and why, contrary to Freud’s suggestion, mourning’s work is never completed.