The mechanisms by which cells become polarised in the plane of an epithelium have been studied in Drosophila for many years. Work has focussed on two key questions: firstly, how individual cells adopt a defined polarity, and secondly how the polarity of each cell within a tissue is aligned with its neighbours. It has been established that asymmetric subcellular localisation of a number of polarity proteins is an essential mechanism underlying polarisation of single cells. The process by which this polarity (...) is coordinated between cells however is less well understood, but is thought to involve gradients of activity of the atypical cadherins Dachsous and Fat. Subsequently, this long‐range polarity signal is refined by local cell–cell interactions involving the transmembrane molecules Frizzled, Strabismus and Flamingo. The role of these factors in coordinating polarity will be discussed. BioEssays 27:1218–1227, 2005. © 2005 Wiley Periodicals, Inc. (shrink)

The “Slicing Problem” is a thought experiment that raises questions for substrate-neutral computational theories of consciousness, including those that specify a certain causal structure for the computation like Integrated Information Theory. The thought experiment uses water-based logic gates to construct a computer in a way that permits cleanly slicing each gate and connection in half, creating two identical computers each instantiating the same computation. The slicing can be reversed and repeated via an on/off switch, without changing the amount of matter (...) in the system. The question is what do different computational theories of consciousness believe is happening to the number and nature of individual conscious units as this switch is toggled. Under a token interpretation, there are now two discrete conscious entities; under a type interpretation, there may remain only one. Both interpretations lead to different implications depending on the adopted theoretical stance. Any route taken either allows mechanisms for “consciousness-multiplying exploits” or requires ambiguous boundaries between conscious entities, raising philosophical and ethical questions for theorists to consider. We discuss resolutions under different theories of consciousness for those unwilling to accept consciousness-multiplying exploits. In particular, we specify three features that may help promising physicalist theories to navigate such thought experiments. (shrink)

This is a new release of the original 1955 edition.

In 1971, John Rawls published A Theory of Justice, the burden of which was strongly egalitarian. But Rawls eventually came to the conclusion that the project of working out a stable, well‐ordered society as argued in A Theory of Justice had failed. In 1993, in Political Liberalism, Rawls sought to establish a sounder theoretical foundation for a stable, well‐ordered society. Rawls was widely viewed, however, as having given up egalitarianism in Political Liberalism ‐ the commitment to a fair distribution, or (...) ‘justice as fairness’, along lines originally developed in A Theory of Justice. I argue, by contrast, that Political Liberalism does not in fact repudiate the egalitarianism of A Theory of Justice. Political liberalism has many variants, including variant conceptions of justice. In the first part of what follows, the question is raised whether political liberalism can defend a conception of justice that is as egalitarian as ‘justice as fairness’. Such a conception would guarantee the fair value of political liberties and would also contain the so‐called ‘difference principal’, which states that social and economic inequalities are to be adjusted so that they are to the greatest benefit of the least advantaged. Although it seems possible to defend such an egalitarian conception of justice, it does not seem necessary, all the same, that all variants of political liberalism should be as egalitarian as justice as fairness. Thus, in the second part of my argument, I seek to overturn, or at least substantially to qualify, the idea that there is no need for political liberalism to be strongly egalitarian. I conclude that the egalitarian credentials of political liberalism have to be bolstered, even more so than Rawls himself seems to think. (shrink)

What is the real significance of covariance anyway, and why should it be regarded as so fundamental ? What we mean by a covariant expression is one whose ...

In a comprehensive assessment of the penetration of Rawls's ideas in the Netherlands since 1971 five debates are discerned in which different aspects are highlighted or play a role. Some of these debates are more or less ongoing ones, some overlap with each other, and some can be pinpointed more precisely in time. In the first 15 years following the publication of A Theory of Justice, attention was focused on the distributive implications of `justice as fairness'. Next, the `liberalism-communitarianism debate' (...) came to the fore. More recently, Kantian aspects of Rawls's theory have been discussed. A fourth, also more recent debate relates to problems of multiculturalism. Finally, in recent years, and more or less in conjunction with the debate on multiculturalism, the current situation of the Dutch welfare state has been discussed. Here we get back to the core of Rawlsian theory, its distributive implications. But now it is argued that this theory focuses too much on equality at the expense of responsibility and incentives. (shrink)

El propósito del estudio que generó el presente artículo fue analizar las percepciones de coordinadores y docentes tutores sobre el desarrollo de competencias generales en estudiantes de pregrado desde la acción tutorial. El estudio se realizó según el enfoque cualitativo y diseño fenomenológico, cuya población la constituyeron coordinadores y docentes tutores de estudiantes de pregrado de una Universidad de Lima desde sus experiencias en la acción tutorial. El tamaño de la muestra se determinó por el criterio de saturación. Los datos (...) se recogieron por medio de una guía de encuesta estructurada y el rigor científico se orientó según criterios de calidad: credibilidad, transferibilidad, dependencia y confirmabilidad. Se encontró como resultado principal que la acción tutorial contribuye al desarrollo de algunas competencias genéricas, tales como las comunicativas escritas y orales, y el trabajo en equipo, que son las más valoradas por la experiencia tutorial, ya que se requiere de comunicación fluida. (shrink)

Questions of political identity and citizenship, raised by thecreation of the `new Europe', pose new questions that politicaltheorists need to consider. Reflection upon the circumstances ofthe new Europe could help them in their task of delineatingconceptual structures and investigating the character ofpolitical argument.Does it make sense to use concepts as `citizenship' and`identity' beyond the borders of the nation-state? What does itmean when we speak about `European Citizenship' and `EuropeanIdentity'?It is argued that the pluralism that has led theorists tooffer a conception (...) of citizenship based upon principles of right,rather that the common good, applies even more strongly at thelevel of the European political order. Developing a contractariantheory of federation, an account of the basis of a Europeancitizenship will be offered in which federalism emerges out of anoverlapping consensus of European citizens on the terms of theirpolitical association.`European Citizenship' and `European Identity' are discussedin the context of the so-called `European Union', and not in thewider context of Europe `as a whole', or for that matter on aneven broader `cosmopolitan' scale. However, the gist of the articleis that arguments for concepts of `citizenship' and `identity'that go beyond borders of nation-states and that are applied tothe `European Union', could have implications for an even widerapplication.Finally, and in conclusion, the (empirical) context will beelaborated in which the normative concept of shared liberalcitizenship identity should be realized on a pan-national,European level. (shrink)

What is a just political order? What does justice require of us? These are perennial questions of political philosophy. John Rawls, generally acknowledged to be one of the most influential political philosophers of the twentieth century, answered them in a way that has drawn widespread attention, not only from political philosophers, but from political scientists, economists, those in the field of public policy, and experts in jurisprudence. It is not only academics who have been inspired by Rawls' ideas; they have (...) also influenced the theory of government and continue to play a role in actual public political debates. This introduction outlines Rawls' work on the theory of justice. Focusing on Rawls' own writings, from his first publication in 1951 to his final ones some fifty years later, Percy B. Lehning demonstrates how and why they can be considered as one consistent and coherent body of work. (shrink)

Beschrijving van het leven en gedachtegoed van de Amerikaanse rechtsfilosoof John Rawls, die in zijn werk een filosofisch concept uitwerkte van een samenleving waarin vrijheid en gelijkheid beide tot hun recht zouden komen.