Laurence Bonjour

Replies and Clarifications

I wish to express my gratitude to the authors of the foregoing essays for the impressive skill and care that they have expended on my work. They have done so well that I have not surprisingly found it impossible to deal adequately with all that they have said in the space available to me in the present volume. Thus while I have done my best to focus on the most important and potentially telling criticisms, there are some valuable points which have been omitted from the present discussion and others with regard to which I have been unable to do much more than suggest a line of response, postponing more detailed consideration and argument to other occasions. I have also confined myself entirely to discussions directed explicitly at my views, which has meant ignoring much that is of interest in the essays in the other sections of the present volume. To make things a bit less chaotic for the reader, I have adopted the organizing principle of dealing with topics in roughly the same order in which the corresponding discussions occur in The Structure of Empirical Knowledge 1 (hereafter SEK).

Reply to Solomon

The first objection appeals to the familiar idea that theories are underdetermined by evidence. Solomon argues that there will always be many possible alternative and incompatible systems of belief which satisfy all of the coherentist justificatory constraints to which the metajustificatory argument appeals, i.e. which are equally coherent, satisfy the observation requirement, and remain stable over time. Since these different systems cannot all be likely to be true in the realist sense of truth invoked by the argument, the argument must fail. I think that Solomon is right that some degree of underdetermination is unavoidable, that different systems of belief that are logically incompatible with each other may be equally justified. But how a serious a problem this poses for the metajustificatory argument will depend on how radical the underdetermination is, i.e. on how far such alternative systems of belief diverge from each other. If the divergence is small enough, if the different alternatives are in effect close variations on a common theme, then it will still be possible to say, invoking a familiar notion from discussions in the philosophy of science, that a system that satisfies the justificatory constraints is likely to be at least approximately true and this seems to me enough to save the basic thrust of the argument. The intelligibility of the concept of approximate truth has sometimes been challenged, but I think that we can do well enough for present purposes by saying that a belief is approximately true if a vaguer, less specific

Skepticism, Justification, and Explanation.

1 An Argument for the Explanatory Foundational Theory and Against Skepticism.- I: Skepticism and the Foundations of Justification.- 2 Skepticism and a Foundation of Certainty.- 3 Skepticism and Acceptability without Certainty.- 4 Skepticism and the Probability of Nonbasic Statements (I): On Sufficient Conditions for Absolute Probabilities.- 5 Skepticism and the Probability of Nonbasic Statements (II): On Sufficient Conditions for Conditional Probabilities.- II: An Examination of Nonfoundational Theories.- 6 Foundational Versus Nonfoundational Theories of Justification.- 7 A Foundational Theory with Explanatory Coherence.- 8 Explanatory Systems: Conditions of Adequacy and Systemic Tests.- 9 The Systemic Tests of Economy and Simplicity.- 10 The Explanatory Foundational Theory and Skepticism.- 11 Summary and Concluding Remarks.- A Bibliographic Essay (Walter N. Gregory).- Index of Names.- Index of Subjects.

Rescher’s Epistemological System

The main focus of Rescher’s recent work has been epistemology. In a series of interrelated books and articles,1 he has developed a comprehensive and novel epistemological position, one which is both labyrinthine in its complexity and also radically and deliberately eclectic. The resulting epistemological system defies any simple characterization or assessment. In this paper, I shall neglect many of its aspects in order to focus on what is arguably its core: Rescher’s account of the manner in which a theory of empirical knowledge is itself to be justified. Thus, adapting a familiar distinction from moral philosophy, our primary concern will be with Rescher’s meta-epistemological position, as opposed to his normative-epistemological position (though the distinction between these two is in the end much less sharp for Rescher than it is for most epistemologists). Focusing on the meta-epistemological issue will give us a thread which we may hope to follow through some selected parts of the labyrinthe without losing our way altogether.