Logical pluralism is the view according to which there is more than one relation of logical consequence, even within a given language. A recent articulation of this view has been developed in terms of quantification over different cases: classical logic emerges from consistent and complete cases; constructive logic from consistent and incomplete cases, and paraconsistent logic from inconsistent and complete cases. We argue that this formulation causes pluralism to collapse into either logical nihilism or logical universalism. (...) In its place, we propose a modalist account of logical pluralism that is independently well motivated and that avoids these collapses. (shrink)

The medieval Islamic solutions to the liar paradox can be categorized into three different families. According to the solutions of the first family, the liar sentences are not well-formed truth-apt sentences. The solutions of the second family are based on a violation of the classical principles of logic (e.g. the principle of non-contradiction). Finally, the solutions of the third family render the liar sentences as simply false without any contradiction. In the Islamic tradition, almost all the well-known solutions of the (...) third family are inspired by the solution proposed by At_īr al-Dīn al-Abharī (d. 1265). Providing a logical analysis of his discussion of the liar paradox, I show that his solution is based on a conception of truth according to which every sentence signifies, usually among other things, its own truth. This makes Abharī’s solution of the same spirit as certain solutions that were later developed in the Latin tradition, in particular by John Buridan (d. 1358) and Albert of Saxony (d. 1390). (shrink)

Is there a poetic ground in Peirce's philosophy? While this question may sound interesting, it is somehow odd, as Peirce is well–known as a logician, and it is also known by scholars that he was not an expert in poetry, literature, art, or even theories concerning art in general. This paper hypothesizes that there is a starting point in his philosophy that is poetical in its nature. Moreover, Peirce's system is obviously logical in its form, but also keeps the (...) spirit of the original silent feeling of poetry that seems to have fascinated him. Also, I claim there is a Schellingian heritage in Peirce's philosophy that is partially responsible for that poetic starting point. This idea also has, as a support, the supposition that a realistic view of the world provides a hypothesis of symmetry between the human and natural worlds, which provides the basic form for his ontological theories and for the theoretical harmony among Peirce's doctrines. This quality of Peirce's philosophy is a kind of a Greek beauty that is only evident for those who can view his thought not in fragments but as a complex system that has the potency of not only answering classical philosophical questions, but also of giving rise to a new philosophy which needs to be further developed. (shrink)

Anti-exceptionalism about logic is the Quinean view that logical theories have no special epistemological status, in particular, they are not self-evident or justified a priori. Instead, logical theories are continuous with scientific theories, and knowledge about logic is as hard-earned as knowledge of physics, economics, and chemistry. Once we reject apriorism about logic, however, we need an alternative account of how logical theories are justified and revised. A number of authors have recently argued that logical theories (...) are justified by abductive argument (e.g. Gillian Russell, Graham Priest, Timothy Williamson). This paper explores one crucial question about the abductive strategy: what counts as evidence for a logical theory? I develop three accounts of evidential confirmation that an anti-exceptionalist can accept: (1) intuitions about validity, (2) the Quine-Williamson account, and (3) indispensability arguments. I argue, against the received view, that none of the evidential sources support classical logic. (shrink)

This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work is in the public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and (...) made generally available to the public. To ensure a quality reading experience, this work has been proofread and republished using a format that seamlessly blends the original graphical elements with text in an easy-to-read typeface. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant. (shrink)

According to a longstanding philosophical tradition dating back to Aristotle, certain proofs do not only certify the truth of their conclusion but also explain it. Lately, much effort is being devo...

Following the speech act theory, we take hypotheses and assertions as linguistic acts with different illocutionary forces. We assume that a hypothesis is justified if there is at least a scintilla of evidence for the truth of its propositional content, while an assertion is justified when there is conclusive evidence that its propositional content is true. Here we extend the logical treatment for assertions given by Dalla Pozza and Garola by outlining a pragmatic logic for assertions and hypotheses. On (...) the basis of this extension we analyse the standard logical opposition relations for assertions and hypotheses. We formulate a pragmatic square of oppositions for assertions and a hexagon of oppositions for hypotheses. Finally, we give a mixed hexagon of oppositions to point out the opposition relations for assertions and hypotheses. (shrink)

The thesis of this paper is that scientific method is to be thought of as a complex many-leveled regulatory hierarchy of principles, interacting with theory also viewed as a complex many-leveled hierarchy. This conception of method is illustrated in particular through one episode in the contemporary development of plasma physics, and related to others. It provides for method-theory interaction and for the development of method itself as science develops.

This book aims to offer an account of conscious experience and of concepts that help us understand empirical reasoning and empirical dialectic. The account offered possesses, it is claimed, two virtues. First, it provides great theoretical freedom. It allows the theoretician freedom to radically reconceive the world. The theoretician may, for example, begin with the conception that colors are genuine qualities of physical bodies and may, in light of empirical findings, shift to the conception that colors are not genuine qualities (...) at all. Second, the account grants empirical reason a great power to constrain: empirical reason can force a particular conception of the self and the world on the rational inquirer. These seemingly contrary virtues are reconciled through a novel treatment of presentation and appearances in the account offered of conscious experience and a novel treatment of ostensive definitions in the account offered of concepts. The argument of the book is buttressed by a critical study of the principal approaches to experience and reason found in the philosophical literature.--. (shrink)

Following an approach that is empirical but not psychological, and dialectical but not dialogical, in this book Maurice Finocchiaro defines concepts such as reasoning, argument, argument analysis, critical reasoning, methodological reflection, judgment, critical thinking, and informal logic. Including extended critiques of the views of many contemporary scholars, he also integrates into the discussion Arnauld's Port-Royal Logic, Gramsci's theory of intellectuals, and case studies from the history of science, particularly the work of Galileo, Newton, Huygens, and Lavoisier.

Provides an integrated introduction to artificial intelligence. Develops AI representation schemes and describes their uses for diverse applications, from autonomous robots to diagnostic assistants to infobots. DLC: Artificial intelligence.

The standard notion of formal theory, in logic, is in general biased exclusively towards assertion: it commonly refers only to collections of assertions that any agent who accepts the generating axioms of the theory should also be committed to accept. In reviewing the main abstract approaches to the study of logical consequence, we point out why this notion of theory is unsatisfactory at multiple levels, and introduce a novel notion of theory that attacks the shortcomings of the received notion (...) by allowing one to take both assertions and denials on a par. This novel notion of theory is based on a bilateralist approach to consequence operators, which we hereby introduce, and whose main properties we investigate in the present paper. (shrink)

Can God create a stone too heavy for him to lift? Can time have a beginning? Which came first, the chicken or the egg? Riddles, paradoxes, conundrums--for millennia the human mind has found such knotty logical problems both perplexing and irresistible. Now Roy Sorensen offers the first narrative history of paradoxes, a fascinating and eye-opening account that extends from the ancient Greeks, through the Middle Ages, the Enlightenment, and into the twentieth century. When Augustine asked what God was doing (...) before He made the world, he was told: "Preparing hell for people who ask questions like that." A Brief History of the Paradox takes a close look at "questions like that" and the philosophers who have asked them, beginning with the folk riddles that inspired Anaximander to erect the first metaphysical system and ending with such thinkers as Lewis Carroll, Ludwig Wittgenstein, and W.V. Quine. Organized chronologically, the book is divided into twenty-four chapters, each of which pairs a philosopher with a major paradox, allowing for extended consideration and putting a human face on the strategies that have been taken toward these puzzles. Readers get to follow the minds of Zeno, Socrates, Aquinas, Ockham, Pascal, Kant, Hegel, and many other major philosophers deep inside the tangles of paradox, looking for, and sometimes finding, a way out. Filled with illuminating anecdotes and vividly written, A Brief History of the Paradox will appeal to anyone who finds trying to answer unanswerable questions a paradoxically pleasant endeavor. (shrink)