In recent years considerable attention has been focused on the question whether Plato ever uses arguments he knows to be sophistical, especially whether he puts such arguments into the mouth of Socrates. Though differing views have been held, at the present time the majority of scholars seem to believe that Plato does not. Though I disagree with this position, I will not attack it directly in this paper. Instead I will discuss what I take to be an important preliminary matter, (...) establishing criteria that can be employed in order to assess the claim that one of Plato's characters does or does not argue sophistically. Since the case of Socrates is by far the most important, I will limit discussion here to the question whether Socrates ever uses sophistry. (shrink)

Response to commentaries on keynote article.

John Buridan was a fourteenth-century philosopher who enjoyed an enormous reputation for about two hundred years, was then totally neglected, and is now being 'rediscovered' through his relevance to contemporary work in philosophical logic. The final chapter of Buridan's Sophismata deals with problems about self-reference, and in particular with the semantic paradoxes. He offers his own distinctive solution to the well-known 'Liar Paradox' and introduces a number of other paradoxes that will be unfamiliar to most logicians. Buridan also moves on (...) from these problems to more general questions about the nature of propositions, the criteria of their truth and falsity and the concepts of validity and knowledge. This edition of that chapter is intended to make Buridan's ideas and arguments accessible to a wider range of readers. The volume should interest many philosophers, linguists and logicians, who are increasingly finding in medieval work striking anticipations of their own concerns. (shrink)

In this paper we consider an intuitionistic variant of the modal logic S4 (which we call IS4). The novelty of this paper is that we place particular importance on the natural deduction formulation of IS4— our formulation has several important metatheoretic properties. In addition, we study models of IS4— not in the framework of Kirpke semantics, but in the more general framework of category theory. This allows not only a more abstract definition of a whole class of models but also (...) a means of modelling proofs as well as provability. (shrink)

According to the prevailing sentiment, changing the past is logically impossible. The prevailing sentiment is wrong. In this paper, I argue that the claim that changing the past entails a contradiction ultimately rests upon an empirical assumption, and so the conclusion that changing the past is logically impossible is to be resisted. I then present and discuss a model of time which drops the empirical assumption and coherently models changing the past. Finally, I defend the model, and changing the past, (...) against objections. (shrink)

In this paper I will argue that the latter group [of Non-Humeans] is correct. My argument focuses on practical deliberation and has two parts. I will discuss two different problems that arise for the Humean Theory and suggest that while taken individually each problem appears to have a solution, for each problem the solution Humeans offer precludes solving the other problem. I will suggest that to see these difficulties we must take seriously the thought that we can only understand an (...) agent’s reasons for her action by looking at her actual or possible practical deliberation. (shrink)

In ‘Wittgenstein on Language and Rules’, Professor N. Malcolm took us to task for misinterpreting Wittgenstein's arguments on the relationship between the concept of following a rule and the concept of community agreement on what counts as following a given rule. Not that we denied that there are any grammatical connections between these concepts. On the contrary, we emphasized that a rule and an act in accord with it make contact in language. Moreover we argued that agreement in judgments and (...) in definitions is indeed necessary for a shared language. But we denied that the concept of a language is so tightly interwoven with the concept of a community of speakers as to preclude its applicabilty to someone whose use of signs is not shared by others. Malcolm holds that ‘This is an unwitting reduction of Wittgenstein's originality. That human agreement is necessary for “shared” language is not so striking a thought as that it is essential for language simpliciter.’ Though less striking, we believe that it has the merit of being a true thought. We shall once more try to show both that it is correct, and that it is a correct account of Wittgenstein's arguments. (shrink)

The King Report on Corporate Governance (1994) evoked unprecedented interest in corporate governance in South Africa. This does not mean that corporate governance was not an issue of concern before the release of this historical report. To the contrary, corporate governance in its broader sense has been at stake since the inception of the first publicly owned companies in South Africa. This article intends to give an overview of corporate governance in South Africa. It starts by making a distinction between (...) broad and narrow conceptions of corporate governance. Before applying this distinction to the practice of corporate governance in South Africa, a brief overview of the corporate landscape in South Africa is provided. Then the South African situation with regard to broad and narrow corporate governance respectively is analysed. The article ends with a discussion of the review of corporate governance that currently is in the making in South Africa. Throughout the article both the financial and ethical dimensions of corporate governance is attended to. (shrink)

Dealing with the nature of historical knowledge, this book is concerned with both philosophical and historical questions. It involves considerations as various as statistical hypothesis testing, componential analysis and the problem of the Synoptic Gospels. --.

The purpose of this note is to acknowledge a gap in a previous paper, "The complexity of revision," and to provide a corrected version of the argument.

The study of continuous group actions is ubiquitous in mathematics, and perhaps the most general kinds of actions for which we can hope to prove theorems in just ZFC are those where a Polish group acts on a Polish space.For this general class we can find works such as [29] that build on ideas from ergodic theory and examine actions of locally compact groups in both the measure theoretic and topological contexts. On the other hand a text in model theory, (...) such as [12], will typically consider issues bearing on the actions by the symmetric group of all permutations of the integers. More generally [1] shows that the orbit equivalence relations induced by closed subgroups of the infinite symmetric group can be reduced to the isomorphism relation on corresponding classes of countable models.This paper considers a third category formed by the continuous actions of separable Banach spaces on Polish spaces. These examples cannot be subsumed under the two earlier headings, and it is known from [10] that theBorel cardinalitiesof the quotient spaces that arise from such actions are incomparable with the equivalence relations induced by the symmetric group or any locally compact Polish group action.One of the first things to be addressed concerns the complexity of these equivalence relations. This question forappears in [1]. (shrink)

The King Report on Corporate Governance (1994) evoked unprecedented interest in corporate governance in South Africa. This does not mean that corporate governance was not an issue of concern before the release of this historical report. To the contrary, corporate governance in its broader sense has been at stake since the inception of the first publicly owned companies in South Africa. This article intends to give an overview of corporate governance in South Africa. It starts by making a distinction between (...) broad and narrow conceptions of corporate governance. Before applying this distinction to the practice of corporate governance in South Africa, a brief overview of the corporate landscape in South Africa is provided. Then the South African situation with regard to broad and narrow corporate governance respectively is analysed. The article ends with a discussion of the review of corporate governance that currently is in the making in South Africa. Throughout the article both the financial and ethical dimensions of corporate governance is attended to. (shrink)

"This book represents a continuation of the research project in philosophy of language and semantics represented in the journal "Protosociology" at the J. W. ...