In Defense of Pure Reason: A Rationalist Account of A Priori Justification (Cambridge Studies in Philosophy) [Paperback]

Laurence BonJour (Author)

Book Description

Publication Date: November 28, 1997 | Series: Cambridge Studies in Philosophy

This book is concerned with the alleged capacity of the human mind to arrive at beliefs and knowledge about the world on the basis of pure reason without any dependence on sensory experience. Most recent philosophers reject the view and argue that all substantive knowledge must be sensory in origin. Laurence BonJour provocatively reopens the debate by presenting the most comprehensive exposition and defense of the rationalist view that a priori insight is a genuine basis for knowledge.

Editorial Reviews

Review

"...after reading his book we have a much better idea of the direction in which those answers must lie." Mylan Engel, Jr., Dialogue

"This book is an important contribution to the contemporary epistemological literature. The book is tightly organized, crisply argued, and sets the standard against which competing accounts must be measured. BonJour's book is rich and challenging...much can be learned from this book. It is required reading for anyserious student of the field and I entusiastically recommend it to nonspecialists as well." The Philosophical Review

"This work contains interesting criticisms of and rebuttals to opponents of rationalism. In addition it contains a bold, heady, imaginative positive account of pure reason. BonJour's bold answer consists of outlining and arguing for a theory of mental content that is nonrepresentational and at once both externalist as well as internalist. His imaginative conjecture is in the spirit of historic forms of rationalism: it is Aristotelian and Thomistic, in that the intellect in knowing necessary truths is in a sense all things; it is Hegelian in that the project critically argues for the coincidence of the real and the rational." Review of Meta Physics

Book Description

This book is concerned with the alleged capacity of the human mind to arrive at beliefs and knowledge about the world on the basis of pure reason without any dependence on sensory experience. Most recent philosophers reject the view and argue that all substantive knowledge must be sensory in origin. Laurence BonJour provocatively reopens the debate by presenting the most comprehensive exposition and defense of the rationalist view that a priori insight is a genuine basis for knowledge.

Product Details

• Paperback: 248 pages
• Publisher: Cambridge University Press (November 28, 1997)
• Language: English
• ISBN-10: 0521597455
• ISBN-13: 978-0521597456
• Product Dimensions: 8.4 x 5.5 x 0.7 inches
• Shipping Weight: 12.6 ounces (View shipping rates and policies)
• Average Customer Review: 4.2 out of 5 stars  See all reviews (6 customer reviews)
• Amazon Best Sellers Rank: #195,863 in Books (See Top 100 in Books)

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13 of 13 people found the following review helpful:

5.0 out of 5 stars A cogent defense of a priori justification, December 27, 1998

By 

John S. Ryan "Scott Ryan" (Cuyahoga Falls, OH) - See all my reviews
(REAL NAME)   

This review is from: In Defense of Pure Reason: A Rationalist Account of A Priori Justification (Cambridge Studies in Philosophy) (Paperback)

One of the many minor joys of reading this marvelous book is seeing Kant toppled from his rationalist pedestal and pushed into the Humean camp, where he belongs.

But the major joy, as might be expected from the title, is watching BonJour develop a cogent defense of a priori justification.

In the process, he deftly turns aside the objections of empiricism, showing that empiricist accounts themselves depend on implicit use of the a priori.

And in what may be the most significant feature of his own positive account, BonJour acknowledges that a priori justification is _fallible_ but nevertheless cannot, strictly speaking, be refuted by experience; successful refutation always depends on a priori considerations.

Finally, BonJour closes with a promising start toward an a priori theory of induction.

This excellent and workmanlike book belongs on the shelf of anyone interested in understanding and defending the power of reason.

8 of 8 people found the following review helpful:

5.0 out of 5 stars An Incredible Book, February 20, 2002

By 

Abolaji Ogunshola "Realism exponent" (CT) - See all my reviews
(REAL NAME)   

This review is from: In Defense of Pure Reason: A Rationalist Account of A Priori Justification (Cambridge Studies in Philosophy) (Paperback)

My only qualm with this book is that only a reader who has read some philosophy will find it truly accessible. It's length and scope doesn't allow the author to fully discuss many of the issues surrounding the topic of rational insight.

What is rational insight? One of the simplest examples is the syllogism: "All men are mortal. Socrates is a man. Socrates is mortal." Another example is the statement: "Something cannot be both green all over and red all over." I think that only the hardcore skeptic would deny the certainty of such insights. How do we justify/explain such insights? Here comes the rub - to justify such insights, the ability to grasp them must already be possessed by those who are justifying them and those to whom they must be justified. A point later defended by the author, and which has been defended by many rationalists, is that the structure of the world must such that these relationships are given in reality in some form.

Rather than list and categorize these insights, Bonjour mounts a wonderful defence for these insights, which he categorizes, like other rationalist philosophers, as "apriori" knowledge, or in his better term, "apriori justification". He, like other rationalists, describes them as a grasp of necessity: once thier nature is grasped and understood, people defend them by thinking and reasoning, rather than pointing to specific data given in experience.

The book has many wonderful points: a careful and reasoned exposition of why Kant was not a rationalist in the true sense of the word (this has been known to quite a few rationalists in the Aristotleian tradition, but Bonjour's criticism leaves little to the imagination), a defence of view of a priori knowledge as fallible, but fallible only in the sense that it answers to new and better apriori insights when found to be mistaken, and a nice and careful discussion of the major analytic school's objections against a priori knowledge.

A great part of this book is well made and much needed distinctions between the a priori and the a posteriori, the analytic and the synthetic, and the necessary and the contingent. His defence and qualification of these terms are worth the cost of the book alone, and he shows how misrepresentaions of these terms, and thier implications are, have led to the acceptance of weak arguments against them being considered conclusive rejections of them.

Finally, the author gives both the nice defence and the beginnings of an a priori theory of induction. The good thing about his defence is that it validates induction, and it will probably be easy to incorporate the best work that has been done into this field since I believe that Bonjour has silenced the greatest oppositions to induction as a source of knowledge.

It is a short book, and is quite limited in scope, but it was a page turner for me. I believe the influence of this book's arguments will be far reaching, once the required critical mass of intellectuals inculcate the ideas contained within this book.

I think my review is understated, so I will only say this: get the book if you have the philiosophical background, and be prepared for one of the best defences of Reason in philosophical history.

5 of 6 people found the following review helpful:

4.0 out of 5 stars formidable defense of rationalism., September 10, 2005

By 

Lord Chimp (Monkey World) - See all my reviews

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This review is from: In Defense of Pure Reason: A Rationalist Account of A Priori Justification (Cambridge Studies in Philosophy) (Hardcover)

The rationalist position, essentially that knowledge is possible purely on the basis of thinking, would never have required much defense a few hundred years ago. It had always been taken for granted that knowledge could be given a priori justification, without appeal to sensory perception. The anti-rationalist position is a difficult one: indeed, it seems that any meaningful denial of this claim would itself be a priori. Yet this fact has not dissuaded countless intellectuals from either severely disarming a priori justification or rejecting it outright. So, in my view the primary strength of BonJour's work here is to show that all rejections of synthetic a priori justification implicitly depend on synthetic a priori arguments themselves. This is apparent in BonJour's challenges to moderate empiricism, linguistic analysis, and the radical repudiation of apriorism by Professor Quine and his followers. The defensive aspect of this book demonstrates that a rejection of a priori reasoning results in a rejection of reason itself, a position that is untenable if not an outright performative contradiction. Some critics will ultimately latch on to the argument that appeals to a priori justification are ultimately question-begging. I do not find this view plausible, since such objections are also principally a priori in nature.

BonJour's critique of Kant's epistemology, showing him to be closer to empiricism than rationalism, is pretty much on the mark, because Kant's theory of knowledge applies only to one's own subjective categories and not reality in sich. (I believe a constructivist defense of Kant's philosophy can be made, but it requires that a bridge be made between the mind and external reality, something not established by Kant himself.) He also spends considerable time withering away at the all too prevalently held view of the symbolic conception of thought, which in my view is one of the more powerful arguments against the a priori. His argument, in a nutshell, is that the symbolic conception of thought renders thoughts internally inaccessible, and any metaphysical theory which does so must be untenable.

Ultimately, BonJour's thesis is that a priori justification is fallible, but undeniably possible. BonJour feels secure with the position of moderate rationalism he has a adopted, although I believe this conception of reason is a bit weaker than he does, simply because, on my interpretation, BonJour requires less certainty than I would deem necessary to justify a given proposition a priori. A priori justification requires axioms, without it is clearly weaker than it would be otherwise. In his moderate view, there is also the possibility of empirical data refuting a priori justification, and I cannot accept this. If empirical information really "refutes" a priori justification (which I am not convinced is possible), then I would definitely refrain from calling the a priori argument truly _justified_. Furthermore, I think BonJour misses an essential part of a priori justification-that it logically precedes all empirical knowledge. Yet this takes little away from the essence of BonJour's position, which I would accept.

Bear in mind I am most certainly an extreme rationalist, albeit not quite the kind Mr. BonJour has in mind when he discusses the "extreme" rationalist in his book. Therefore, I may sound more critical than I would prefer. Regardless of my own criticism, this is an excellent, fair, and highly-welcome defense of the most maligned source of knowledge in our time.