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Knowledge by Ian Evans and Nicholas D. Smith

Nick Everitt is uncertain about a book on Knowledge.

Over the past half century or so, many investigations into knowledge by philosophers have tried to provide a logical analysis of sentences of the form ‘S [a person] knows that p [an assertion or statement]’. More specifically, they have looked for a set of individually necessary and jointly sufficiently conditions for the truth of sentences of that form, that is, for knowledge. There has been almost universal agreement that two of the necessary conditions for knowledge are that S believes that p is true, and that p is true. But beliefs can happen to be true without being knowledge. It is a convention to describe the final condition or set of conditions which turns true belief into knowledge as the ‘warrant’ to call that belief knowledge. This book by Evans and Smith is principally devoted to providing an account of what this warrant amounts to.

Theories of warrant traditionally divide into ‘internalist’ and ‘externalist’ accounts of it. According to the internalist, someone’s warrant for her true belief being knowledge consists in something internal to her which she is aware of. It might, for example, be the process of reasoning which led to her belief that p; or it might consist in her sensory states (she sees the cat on the mat, and thereby comes to know that the cat is on the mat). By contrast, according to the externalist, warrant can consist in something quite outside the knower’s consciousness. It might consist, for example, in the reliability of the knower’s reasoning or perceptual processes, about which, of course, the knower may have no information.

Two chapters of the book are devoted to an examination of internalist accounts, and a further chapter to the externalist. The authors’ discussion is admirably clear and well-informed, the arguments pro and con are beautifully presented, and the evaluation of those arguments scrupulously fair. Incorporated into this part of the book are interesting discussions of scepticism, and of the response offered to it by contextualism, the theory that the truth of knowledge claims is always partly dependent on the context in which they are uttered.

In the latter half of the book Evans and Smith advance their own account of warrant. This is a version of externalism, in that, with some refinements, it explains warrant in terms of the reliability of all the knower’s relevant cognitive capacities. But they seek to accommodate some versions of internalism by adding that for beings like us humans (but not necessarily for beings with other natural capacities) those relevant cognitive capacities include our ability to engage in conscious reasoning. This allows them to say that when you pick up his lead, Fido can know that he is going for a walk even though he is unable to engage in any process of inductive inference, yet by contrast, if I have a true belief about where you are going on holiday next year, that belief will be knowledge only if I have engaged in a process of reasoning.

This is an interesting account of warrant, but it remains too vague to be fully satisfying. What are ‘all of a knower’s relevant cognitive capacities’? The reference to relevant capacities suggests that on at least some occasions, some of those capacities need not have been activated, but on other occasions their activation is essential. Suppose that I look at a piece of wood, and on the basis of my properly-functioning visual system, I acquire the true belief that the wood is smooth. Do I thereby come to know that the wood is smooth? Or is my sense of touch also a relevant cognitive capacity which I must exercise if I am to know that the wood is smooth? This is only one possible example of a troublingly wide range of cases where the application of the authors’ analysis yields no answer.

Some readers might also feel uncomfortable with the authors’ heavy reliance on ‘our’ intuitions about bizarre thought experiments. Such reliance is standard in contemporary discussions of knowledge, but it does require the reader to have intuitions about such scenarios as the following: Henry is driving through an area containing a number of very realistic-looking fake barns and one real barn. Unbeknown to Henry, the fake barns are all blue, and the one real barn is red. Henry sees the red barn, and believes that he is looking at a red barn. Does he know that he is looking at a (real) barn? (p.136). Evans’ and Smith’s intuition about this case is that Henry does not know that he is looking at a real barn. But it is not clear what can be said against those whose intuitions are the opposite, or those who have no intuitions at all about this or other such cases.

There are one or two slips, and surprising omissions. For example, the authors say that there has been little attention to the sense in which our warranted true beliefs are based on evidence, but there is an extended discussion of precisely this topic in Richard Swinburne’s Epistemic Justification (2001). Or again, the authors are rather dismissive of Robert Nozick’s famous ‘tracking’ account of knowledge, but they make no mention of a more sophisticated and highly praised account of it found in Sherrilyn Roush’s Tracking Truth (2005).

One might also have some reservations whether the topic of knowledge is quite as important as the authors assume. It is true that since the time of the Greeks Western philosophy has been obsessed with knowledge – what it is, how we can get it, in which areas we can get it, and so on. But one might well think that this level of concern is misplaced. In both our practical and theoretical lives, we want our beliefs to be reliable guides to the truth; but in both accepting and attributing responsibility for actions, it is seldom important to know whether S knows that p, as opposed to having a very well founded belief that p. As Bishop Butler sagely observed nearly three hundred years ago, “probability is the very guide of life.”

The book is described on its back cover as an ‘introduction’ to the theory of knowledge; however, it is not a suitable text for total beginners in philosophy, and would serve better as an introduction to a graduate-level study of theories of knowledge. The presupposition of key concepts and modes of argumentation makes it clear that this is a book for an audience already at home with modern analytic philosophy.

Although I have raised one or two reservations, it would be wrong to end on a critical note, for this is an excellent book. The clarity and incisiveness of the arguments, the wealth of references to very recent research papers, and the way in which the authors carry forward contemporary discussion, make this a very valuable addition to the literature on knowledge.

© Nick Everitt 2014

Nick Everitt, now retired, was Senior Lecturer in philosophy at the University of East Anglia. He is the author of The Non-Existence of God (Routledge).

Knowledge, Ian Evans and Nicholas D. Smith, Polity, 2012, 224 pages, £15.99, ISBN: 0745650538

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