For 2,000 years, the standard philosophical model of knowledge was that it could be defined as a justified true belief. According to this way of thinking, we can know, for example, that we are human because [1] we believe ourselves to be human; [2] that belief is justified (others treat us as humans, not as dogs); and [3] the belief is true. This definition, which dates to Plato, was challenged by Edmund Gettier in one of the most influential works of philosophy published in the last century – a three page paper that produced two clear examples of justified true beliefs that could not, in fact, be considered knowledge. Gettier's achievement rests on solid foundations provided by his mastery of the critical thinking skill of analysis. By understanding the way in which Plato – and every other epistemologist – had built their arguments, he was able to identify the relationships between the parts, and the assumptions that underpinned then. That precise understanding was what Gettier required to mount a convincing challenge to the theory – one that was bolstered by a reasoning skill that put his counter case pithily, and in a form his colleagues found all but unchallengeable.

This book enriches our understanding of knowledge and Gettier's challenge, stimulating debate on a central epistemological issue.

What is knowledge? Is it the same as opinion or truth? Do you need to be able to justify a claim in order to count as knowing it? How can we know that the outer world is real and not a dream? Questions like these have existed since ancient times, and the branch of philosophy dedicated to answering them - epistemology - has been active for thousands of years. In this thought-provoking Very Short Introduction, Jennifer Nagel considers the central problems and paradoxes in the theory of knowledge and draws attention to the ways in which philosophers and theorists have responded to them. By exploring the relationship between knowledge and truth, and considering the problem of scepticism, Nagel introduces a series of influential historical and contemporary theories of knowledge, incorporating methods from logic, linguistics, and psychology, using a number of everyday examples to demonstrate the key issues and debates. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.

Offering a philosophical examination of the concept of luck and its relationship to knowledge, this text demonstrates how a more nuanced understanding of the relationship between knowledge and luck can enable us to see past some of the most intractable disputes in the contemporary theory of knowledge.

For 2,000 years, the standard philosophical model of knowledge was that it could be defined as a justified true belief. According to this way of thinking, we can know, for example, that we are human because [1] we believe ourselves to be human; [2] that belief is justified (others treat us as humans, not as dogs); and [3] the belief is true. This definition, which dates to Plato, was challenged by Edmund Gettier in one of the most influential works of philosophy published in the last century – a three page paper that produced two clear examples of justified true beliefs that could not, in fact, be considered knowledge. Gettier's achievement rests on solid foundations provided by his mastery of the critical thinking skill of analysis. By understanding the way in which Plato – and every other epistemologist – had built their arguments, he was able to identify the relationships between the parts, and the assumptions that underpinned then. That precise understanding was what Gettier required to mount a convincing challenge to the theory – one that was bolstered by a reasoning skill that put his counter case pithily, and in a form his colleagues found all but unchallengeable.

Develops a new logic paradigm which emphasizes evidence tracking, including theory, connections to other fields, and sample applications.

With one exception, all of the papers in this volume were originally presented at a conference held in April, 1978, at The Ohio State University. The excep tion is the paper by Wilfrid Sellars, which is a revised version of a paper he originally published in the Journal of Philosophy, 1973. However, the present version of Sellars' paper is so thoroughly changed from its original, that it is now virtually a new paper. None of the other nine papers has been published previously. The bibliography, prepared by Nancy Kelsik, is very extensive and it is tempting to think that it is complete. But I believe that virtual com pleteness is more likely to prove correct. The conference was made possible by grants from the College of Human ities and the Graduate School, Ohio State University, as well as by a grant from the Philosophy Department. On behalf of the contributors, I want to thank these institutions for their support. I also want to thank Marshall Swain and Robert Turnbu~l for early help and encouragement; Bette Hellinger for assistance in setting up the confer ence; and Mary Raines and Virginia Foster for considerable aid in the pre paration of papers and many other conference matters. The friendly advice of the late James Cornman was also importantly helpful. April,1979 GEORGE S. PAPPAS ix INTRODUCTION The papers in this volume deal in different ways with the related issues of epistemic justification or warrant, and the analysis of factual knowledge.