Abstract

I begin my investigation of certain aspects of knowledge by arguing that an analysis may legitimately introduce undefined technical terms if the use of these terms can be satisfactorily explained in some other way than by explicit definition, and the analysis provides fruitful direction to further investigation of the analysandum. Two analyses of 'S knows that p' are proposed. The first introduces the expression 'defeated justification'. The second introduces the technical expression: 'justified relative to deviant conditions'. The technical expressions are explained, and the analyses are shown to be equivalent. ;Deviant conditions often lead to defeated justification, and thus to the possibility of justified true belief without knowledge. In the normal course of inquiry, we are justified in the absence of evidence to the contrary in neglecting the possibility that conditions are deviant in relevant respects. This is just to say that we are justified in holding beliefs which are justified in the ordinary ways, without first investigating whether or not these ordinary justifications are defeated. I argue that the justification of this neglect is explained in part by the ways we learn certain words, and that this justification is best understood as a priori--not dependent upon the possession of empirical evidence. ;From the a priori justification of practices of inquiry, it is a short step to the a priori justification of belief in propositions which embody the principles governing those practices. A more general account of a priori justification based on certain features of language-learning is developed, and applied to the field of ethics and the mathematical sciences of arithmetic, geometry, and set theory. ;These results, obtained through an investigation of the role in inquiry of deviant conditions, suggest that my proposed analysis of 'S knows that p' does indeed provide a fruitful direction for investigation of knowledge. Various extensions of my own investigation are proposed, and I conclude with a brief discussion of the relevance of recent attacks on the field of epistemology to that investigation