A Priori Justification

A comprehensive defence of the rationalist view that insight independent of experience is a genuine basis for knowledge.

This book deals with questions about the nature of a priori knowledge and its relation to empirical knowledge. Until the twentieth century, it was more or less taken for granted that there was such a thing as a priori knowledge, that is, knowledge whose source is in reason and reflection rather than sensory experience. With a few notable exceptions, philosophers believed that mathematics, logic and philosophy were all a priori. Although the seeds of doubt were planted earlier on, by the early twentieth century, philosophers were widely skeptical of the idea that there was any nontrivial existence of a priori knowledge. By the mid to late twentieth century, it became fashionable to doubt the existence of any kind of a priori knowledge at all. Since many think that philosophy is an a priori discipline if it is any kind of discipline at all, the questions about a priori knowledge are fundamental to our understanding of philosophy itself.

The topic of a priori knowledge has been central to analytic philosophy for the past two centuries. Casullo's book, based on previously published and unpublished work, systematically addresses questions that have, since Kant, formed the core of the debate.

This book is a collection of essays concerning the concept and existence of a priori knowledge, and the relationship between a priori knowledge and the related concepts of necessary truth and analytic truth.

The major divide in contemporary epistemology is between those who embrace and those who reject a priori knowledge. Albert Casullo provides a systematic treatment of the primary epistemological issues associated with the controversy. By freeing the a priori from traditional assumptions about the nature of knowledge and justification, he offers a novel approach to resolving these issues which assigns a prominent role to empirical evidence. He concludes by arguing that traditional approaches to the a priori, which focus primarily on the concepts of necessity and analyticity, are misguided.

For centuries philosophers have attached much importance to a priori knowledge, but recent work in epistemology and experimental philosophy has questioned this. Leading philosophers discuss explanations of the a priori, challenges to its existence, the status of intuition, and the justification of belief—topics at the centre of current debate.

In recent years many influential philosophers have advocated that philosophy is an a priori science. Yet very few epistemology textbooks discuss a priori knowledge at any length, focusing instead on empirical knowledge and empirical justification. As a priori knowledge has moved centre stage, the literature remains either too technical or too out of date to make up a reasonable component of an undergraduate course. Edwin Mares book aims to rectify this. This book seeks to make accessible to students the standard topics and current debates within a priori knowledge, including necessity and certainty, rationalism, empiricism and analyticity, Quine's attack on the a priori, Kantianism, Aristotelianism, mathematical knowledge, moral knowledge, logical knowledge and philosophical knowledge.

Richard Swinburne offers an original treatment of a question at the heart of epistemology: what makes a belief a rational one, or one which the believer is justified in holding? He maps the various totally different and purportedly rival accounts that philosophers give of epistemic justification ('internalist' and 'externalist'), and argues that they are really accounts of different concepts. He distinguishes (as most epistemologists do not) between synchronic justification (justification at a time) and diachronic justification (synchronic justification resulting from adequate investigation) — both internalist and externalist. He argus that most kinds of justification are worth having because (for different reasons) indicative of truth. However, it is only justification of intermalist kinds that can guide a believer's actions. Swinburne goes on to show the usefulness of the probability calculus in elucidating how empirical evidence makes beliefs probably true: every proposition has an intrinsic probability (an a priori probability independent of empirical evidence) which may be increased or decreased by empirical evidence. This innovative and challenging book will refresh epistemology and rewrite its agenda.

A new approach to Hume's problem of induction that justifies the optimality of induction at the level of meta-induction. Hume's problem of justifying induction has been among epistemology's greatest challenges for centuries. In this book, Gerhard Schurz proposes a new approach to Hume's problem. Acknowledging the force of Hume's arguments against the possibility of a noncircular justification of the reliability of induction, Schurz demonstrates instead the possibility of a noncircular justification of the optimality of induction, or, more precisely, of meta-induction (the application of induction to competing prediction models). Drawing on discoveries in computational learning theory, Schurz demonstrates that a regret-based learning strategy, attractivity-weighted meta-induction, is predictively optimal in all possible worlds among all prediction methods accessible to the epistemic agent. Moreover, the a priori justification of meta-induction generates a noncircular a posteriori justification of object induction. Taken together, these two results provide a noncircular solution to Hume's problem. Schurz discusses the philosophical debate on the problem of induction, addressing all major attempts at a solution to Hume's problem and describing their shortcomings; presents a series of theorems, accompanied by a description of computer simulations illustrating the content of these theorems (with proofs presented in a mathematical appendix); and defends, refines, and applies core insights regarding the optimality of meta-induction, explaining applications in neighboring disciplines including forecasting sciences, cognitive science, social epistemology, and generalized evolution theory. Finally, Schurz generalizes the method of optimality-based justification to a new strategy of justification in epistemology, arguing that optimality justifications can avoid the problems of justificatory circularity and regress.