This contribution is a gentle introduction to so-called dynamic epistemic logics, that can describe how agents change their knowledge and beliefs. We start with a concise introduction to epistemic logic, through the example of one, two and finally three players holding cards; and, mainly for the purpose of motivating the dynamics, we also very summarily introduce the concepts of general and common knowledge. We then pay ample attention to the logic of public announcements, wherein agents change their knowledge as the (...) result of public announcements. One crucial topic in that setting is that of unsuccessful updates: formulas that become false when announced. The Moore-sentences that were already extensively discussed at the conception of epistemic logic in Hintikka’s ‘Knowledge and Belief ’ (1962) give rise to such unsuccessful updates. After that, we present a few examples of more complex epistemic updates. (shrink)

There is currently a debate over whether cognitive architecture is classical or connectionist in nature. One finds the following three comparisons between classical architecture and connectionist architecture made in the pro-connectionist literature in this debate: (1) connectionist architecture is neurally plausible and classical architecture is not; (2) connectionist architecture is far better suited to model pattern recognition capacities than is classical architecture; and (3) connectionist architecture is far better suited to model the acquisition of pattern recognition capacities by learning than (...) is classical architecture. If true, (1)-(3) would yield a compelling case against the view that cognitive architecture is classical, and would offer some reason to think that cognitive architecture may be connectionist. We first present the case for (1)-(3) in the very words of connectionist enthusiasts. We then argue that the currently available evidence fails to support any of (1)-(3). (shrink)

This essay explores some concerns about the quality of informed consent in patients whose autonomy is diminished by fatal illness. It argues that patients with diminished autonomy cannot give free and voluntary consent, and that recruitment of such patients as subjects in human experimentation exploits their vulnerability in a morally objectionable way. Two options are given to overcome this objection: (i) recruit only those patients who desire to contribute to medical knowledge, rather than gain access to experimental treatment, or (ii) (...) provide prospective subjects the choice to participate in standard doubleblind study or receive the experimental treatment. Either option would guarantee that patients in desperate conditions are given a more meaningful choice and a richer freedom, and thus a higher quality of informed consent, than under standard randomized trials. (shrink)

Predation and escaping from predation through hiding are two fundamental phenomena in ecology. The most common approach to reducing the chance of predation is to use a refuge. Here, we consider a three species fishery model system with prey refuge induced by a Holling type-II functional response. These three species of fish populations are named prey, middle predator, and top predator. Harvesting is employed in most fishery models to achieve both ecological and commercial benefits. Research proves that non-linear harvesting (Michaelis–Menten (...) type) returns more realistic outcomes. So, we have combined the Michaelis–Menten type of harvesting efforts for all populations. Uniform boundedness conditions for the solutions of the model are discussed. The existence conditions for possible equilibrium points with stability are presented. We explain the dynamical behavior at each equilibrium point through bifurcation analysis. The persistent criteria of the system are examined. Bionomic equilibrium and optimal harvesting control using Pontryagin’s maximum principle are calculated. For validation of the model in the real world, we have implemented this in the freshwater ecosystem of Lake Victoria. Extraction of native fish species and ecological balances are the foremost solicitude of Lake Victoria. We may resolve this concern partially by implementing prey refuge, since it may sustain the ecology of Lake Victoria, and therefore also its economical importance. Lake Victoria is acclaimed worldwide for the trade of fishing. Also, it provides the largest employment in east-central Africa and is beneficial to fishing equipment manufacturers. So, the bionomic equilibrium and harvesting control have significant applications in the fisheries. All the analytical studies are verified by numerical simulations. We have plotted phase portraits, bifurcation diagrams, Lyapunov exponents to explore the dynamics of the proposed model. (shrink)

At various times in his "Pre-critical" and "Critical" periods, Kant presented an argument about the nature of space that has come to be called the "Incongruous Counterparts" argument. First presented in his 1768 essay, Concerning the Ultimate Foundation for the Differentiation of Regions in Space, the argument holds that two objects, such as two human hands, might be exact counterparts, that is, identical in "size and proportion and... the situation of the parts relative to each other," and yet might be (...) still "incongruent," that there is no continuous rigid motion which brings them into coincidence in space; or, that they are, though counterparts, incongruently left and right hands. This argument appears in 1768, in the Dissertation of 1770, the Prolegomena of 1783 and the Metaphysical Foundations of Natural Science in 1786. Unfortunately, while the details of the argument are virtually the same, the conclusions are not. Kant seems to have claimed that the argument shows: that a Leibnizean, relational theory of space was wrong; that a theory of absolute space was correct; that space was a pure form of sensibility and that space was transcendentally ideal, i.e., that space was not and could not be a feature of things in themselves. In the secondary literature, commentators who have dealt with this issue have simply noted the odd history of the argument and lamented it. Buroker's ambitious and interesting thesis in this book is not only that Kant's use of the argument is consistent and interconnected, but that the argument can be seen as the "origin" of Kant's idealism. She argues both of these points by arguing, in the great majority of cases, more for a logical than an actual or historical connection among the conclusions Kant drew from the argument; i.e., that she can illuminate the reasoning that led Kant from a rejection of Leibniz's relational view to his radical separation between sensibility and understanding, and then to his view that things in themselves are both unknowable and non-spatial. (shrink)

An unorganized but interesting collection of ten papers describing and evaluating the use of computers in legal research and the use of modern behavioral science in analyzing and predicting judicial decisions. The authors are professors of law, lawyers, and social scientists, and include a Soviet scholar writing on cybernetics and Soviet law. Technical descriptions of data recovery systems and technical methods of analyzing judicial decisions alternate with arguments for and against the actual use of such methods and systems by practicing (...) lawyers. All of the technical discussion is within the grasp of the interested lay reader; but the evaluation of these techniques becomes unspecific and polemical at times. The footnotes of many of the papers provide an excellent bibliography.—R. B. P. (shrink)

The author of this polemical book directs his attack more against what he sees as the overwhelmingly dominant "Kantianism" of "contemporary scientific thinking" than against the "Kant" of his title. This is, his book is much more a very general indictment of the "spirit" of this modern mode of knowing, than anything approaching an examination of Kant’s views.

There is a central issue which runs through most of the details of Walker’s interpretation—the relationship between what he calls, taking his cue from Strawson, "transcendental idealism" and "transcendental arguments." He argues often and, I think, correctly, that the contemporary attempt to reconstruct Kant "austerely" in terms of transcendental arguments alone is misguided, that transcendental arguments about "what must be the case in order for there to be experience at all" cannot accomplish their task, and that we should rest content (...) with the more modest goal of discussing those aspects of our nonempirical "thoughts" or "beliefs" about the world which seem indispensably involved in our experience. Of course, we would still need something like a "transcendental argument" to establish these subjective conditions, but Walker uses that term to refer exclusively to Strawson’s austere reconstruction, and to argue that only Kant’s idealistic use of such arguments comes close to philosophic success. (shrink)

Professor MacIntyre has here collected twenty-three of his essays. They range in topics from discussions of psychoanalysis to the relation between reasons and causes in accounts of human action. Indeed, the very range of such issues is part of the point of the book itself. In part 1 of the book, MacIntyre has collected some of the articles he has written over the last fifteen years or so for Encounter, New York Review of Books, and Partisan Review; in part 2, (...) the more traditionally philosophic pieces which first appeared in Philosophy, Philosophical Review, and Journal of Philosophy; by collecting both sets of essays within one set of covers, he has tried to make a point about the relation between such apparently different intellectual contexts. Most broadly, that point has to do with the common problem of "ideology" as it is found in each arena, whether as some explicit, historically achieved "self-image" by means of which individuals struggle "to provide the light that our individual and social lives need", or as the problem of the general role beliefs, reasons, desires, and the like should be said to play in human action, in what way such factors are related to causal explanations of action, and how decisions about such questions affect any view of what a social science is. MacIntyre believes that these somewhat more practical and more theoretical contexts need to be thought together, first because reflection on current, dominant ideologies greatly needs the benefit of "detailed, analytical conceptual inquiries," and because that analysis itself has often paid insufficient attention to its own broader, historical, even ideological context, and the effect such a context can have on methodology. Thus, while it is of the utmost importance to analyze thoroughly and as clearly as possible the language of morals, the methodology of that analysis alone cannot help in determining whether such a language is indeed the language only within which moral discourse can take place, and might also fail to appreciate historical alterations in the meaning of important terms. (shrink)

The United States District Court of Kansas, in Gudenkauf v. Stauffer, Znc., granted the defendants motion for summary judgment for the plaintiff's claims of pregnancy-related discrimination under the Americans with Disabilities Act and the Family and Medical Leave Act of 1993, but the court denied a similar motion for the plaintiff's claim under the Pregnancy Discrimination Act. The court found summary judgment to be appropriate for the ADA claim based on its finding that the plaintiff's pregnancy did not constitute an (...) impairment as required by the statute; as for the FMLA claim, it determined that the defendants failure to grant the plaintiff's leave request did not violate the statute. However, the court determined that summary judgment was inappropriate for the PDA claim because of material questions of fact about whether the defendant had acted with discriminatory intent.In considering the motions for summary judgment, the court accepted the following facts as incontrovertible. Plaintiff Michaela Gudenkauf worked for the defendant Stauffer, Inc. (shrink)

We interpret the concept of determinism for a classical system as the requirement that the solution to the Cauchy problem for the equations of motion governing this system be unique. This requirement is generally believed to hold for all autonomous classical systems. Our analysis of classical electrodynamics in a world with one temporal and one spatial dimension provides counterexamples of this belief. Given the initial conditions of a particular type, the Cauchy problem may have an infinite set of solutions. Therefore, (...) random behavior of closed classical systems is indeed possible. With this finding, we give a qualitative explanation of how classical strings can split. We propose a modified path integral formulation of classical mechanics to include indeterministic systems. (shrink)