Goodbye Descartes

Negative reviews of this book "blame the messenger" -- Devlin does an extraordinary job of explaining the state of the art for his chosen topic, yet he is taken to task for not giving the problems he describes a nice, tidy, Hollywood ending. He is being honest. Such solutions don't exist. His topic is an account of why artificial intelligence's assumptions have led to failure delivering the innovations of machinery seen in the Jetsons, innovations which seemed not all that far-fetched for the field in the intellectual "bubble" during its advent in the post-WWII era. Understanding the failure will touch on formal logic, mathematics, linguistics, behavioral decision theory (at the end of the book) and it's clearly unreasonable to expect Devlin will juggle them all judiciously. Trained as a linguist myself (with cursory knowledge in these other fields), I could take exception with simplifying assumptions / infelicities in his account of language's role, but such would be missing the forest for the trees. More generally though, Devlin's critics are blaming the author for not ultimately curing for cancer -- assuming that were his topic -- in an analogous book whose aim is to illustrate why phrenology might be a wrong-headed place to look for a cure in the first place.

Some of the negative reviews of this book have good points. Devlin is less than scholarly, and (big surprise) he does not offer some kind of fully developed logic of the mind at the end. But jebus, what did you expect? This is a great book, but you have to understand the style it is written in. It is written in an intellectual-fun style, attempting to provide a good, thought-provoking read. It does not provide iron-clad argumentation nor does it provide scholarly historical coverage. What it does provide is an easy to read whirlwind tour of the history of logic and linguistics, as well as hundreds of examples of situations where the logical approach to studying the mind has run into roadblocks. I think it is a great book and well worth the read, especially for someone new to either logic or linguistics.

The astonishing thing about human communication is not that it sometimes fails but that failure is so rare. Given the complexities of context, facial expressions, tone, body movements, and grammar, all going in at least two directions, it is truly incredible that it works so well. As the author points out by example, he can write a sentence that no one else has ever created before, and yet there is no difficulty in determining what he means. Understanding human language is a situation where our obviously finite brains are capable of resolving an infinite number of scenarios. The examples given in this book make you appreciate just how much "computing" power there is in the human brain. Many of the theories regarding the instinctive understanding of human language, independent of word order, are considered and often questioned. The gross shortcomings of Artificial Intelligence (AI) are also raised and used to demonstrate that there is now no effective model for how humans process data and make "rational" decisions. Despite all the original promise and hype, AI has been used to solve few problems and even some of the reported successes are clearly very weak when thoroughly examined. Therefore, the argument throughout the book is that there needs to be a new approach to the problems of cognition The arguments are presented in a thoughtful, detailed, and understandable manner. There are times when the arguments do get technical, but they are few and can be skipped without disrupting the flow of the material. At the end, Devlin also argues for a radical rethinking of the last three thousand years of traditional reasoning that dates back to the Greek origins of logic. He uses the phrase "soft mathematics" to describe what he believes the answer to be. Unfortunately, or perhaps necessarily, he is quite vague as to what it is. Devlin only points out that it will be something quite different from the current rigorous reasoning. Raising some profound and fascinating questions regarding fundamental shortcomings in understanding the most human of activities, Devlin is at his best. Whatever your field of interest or background, if you are interested in thinking about thinking, then you must decipher the squiggles that appear on these ages. Published in Journal of Recreational Mathematics, reprinted with permission.

My original review was erroneous. Many examples were counterintuitive, but it turns out they were correct. The book is an excellent exercise.

The previous reader makes the same error with the monty Hall Problem as do many. New Scientist has been running a web discussion on this problem in its "biteback" section (http:www.newscientist.com), after a strongly positive review of "Goodbye Descartes" brought a small deluge of letters from readers who, like the previous reader, had misunderstood not only the correct Monty Hall solution given in the book, but along with it most of the book's argument. Wise readers will decide for themselves who is "right" on this issue. --Keith Devlin