Not Exactly: In Praise of Vagueness by Kees van Deemter

by Kees van Deemter

Our daily lives are full of vagueness or fuzziness. When we describe someone as "tall," for example, it is as though there is a particular height beyond which a person can be considered "tall." In this stimulating book, Kees Van Deemter cuts across various disciplines--including artificial intelligence, logic, and computer science--to illuminate the nature and importance of vagueness. Van Deemter shows why vagueness is both unavoidable and useful, and he demonstrates how tempting--and how wrong--it often is to think in terms of black and white, instead of the richly graded spectrum of the world around us. Vagueness, the author argues, allows us to focus on what matters, leaving out irrelevant details, and adding texture to what would otherwise be unintelligible facts. The embrace of vagueness, however, comes at a price, for when degrees of grey are accepted, concepts like truth, belief, and proof lose their power, and we are banished from that paradise in which truth and falsity are the only possibilities.

Genres: Philosophy, Science, Nonfiction, Linguistics, Psychology

Hardcover

First published January 28, 2010

Reviews

[Alex Klimkewicz · Rating 4 out of 5]

This was an alternatingly very interesting and very complex book that dealt with the topic of the sorites paradox. How many stones make a heap? One surely does not. Neither does one plus another. Nor does adding one more (n+1) . . . thus we have a paradox!

Van Deemter plunges the depths of the measurement scales, but no matter how far down we go there is always some insurmountable fuzziness that neither refined scientific instruments, nor innate human logic can penetrate. What we are left with are vague things which are quantitatively undefined and we must deal with what Dawkins calls "the tyranny of the discontinuous mind" (p. 5). These vague things are mostly changes in unnoticed degrees, such as global warming or population fluctuations.

This book goes off on different tangents concerning classical logic and modern day computer logic, but what I found most interesting was the section on linguistics and the plasticity of language. "Vagueness resides mostly in words. Ambiguity, by contrast, can arise from interactions between grammatical constructions each of which is entirely harmless by itself" (p. 113). That playful phrase Fruit flies like a banana. comes to mind. The author also reminds us that often readers must read between the lines, since what is usually left unsaid is of importance, but this is especially difficult for computers parsing a language.

Ultimately one is left to ponder this: is our universe really truly fuzzy or are we just imperfect beings incapable of seeing the true delineating boundaries of nature? Either way, one could spend hours (or lifetimes) thinking over these Buddhist-like koans:

-- How tall is tall?

-- How old is old?

-- How few is few?

-- How many is many?

-- How warm is warm?

-- How poor is poor? (Would he become rich with one dollar more?)

[Charles · Rating 3 out of 5]

Defining intelligence is a hard task; one of the best ones is the ability to reason correctly using uncertain, incomplete and even contradictory inputs. Few things in life are absolute except of course for after the event occurs, so dealing with uncertainty or vagueness is a fact of life. Expressing uncertainty in a manner where formal or automated reasoning can be applied to the data is a hard task; several attempts to do so have applied systems such as fuzzy logic, sometimes with excellent success and at other times the results have been disappointing.
This is a book where I disagree with one of the premises although the level of presentation, which is for the mass audience, is acceptable. In the promotional flyer there is the statement "Explores a basic but often unnoticed aspect of our lives - the vagueness inherent in many of our expressions and concepts." I encounter and have to deal with vagueness on a daily basis, both personally and professionally and I am certainly not unique. Hardly a day goes by when I do not end up adapting to a situation made more difficult due to the inherent vagueness of human expressions.
My other criticisms are based on the length of the book and the continued stating of various scenarios with inherent vagueness. The intelligent reader is already well aware of the reality of uncertainty in the world, simply piling on more and more examples does nothing to reinforce the premise. What would be more interesting is more emphasis on how humans manage to process the uncertainty well enough to function and reduce the error rate to a tolerable level. Doing that is the very foundation of what intelligent behavior really is.

Published in Journal of Recreational Mathematics, reprinted with permission and this review appears on Amazon

[Jim]

I have not read this yet but saw this interesting interview:

http://www.newscientist.com/blogs/cul...

[Peter · Rating 4 out of 5]

much of this is very very good

[Betsy · Rating 2 out of 5]

Tedious

[Phoenix · Rating 3 out of 5]

Imprecisely, Maybe...

A reasonably interesting topic but I found that with my background in technical writing and statistics there was not that much for me that was new or surprising. The author often belaboured the same points, so it could have been shorter, and the introduction to symbolic logic was top heavy with symbols which could have been off putting - as Roger Penrose once quipped, every equation added to a book drops the readership in half. I was also hoping for something that was a bit more philosophical, along the lines of Douglas Walton's Fallacies Arising from Ambiguity.

For Van Deemter the sorites (heap) paradox is emblematic and he uses it a great deal. Briefly it is a paradox relating to small differences. It is the misconception that if one small change makes no difference then a lot of small changes will not make a difference, such as the loss of a single hair, one at a time, leading to baldness. At some point a threshold is crossed and the word “bald” starts to become applicable. Chapter 4 discusses the case of “Old Number One”, a 1929 Bentley race car, that exemplifies the old paradox of the Ship of Theseus (which surprisingly the author omits). Buyer A wanted the “original” car, but over time the various pieces had been replaced, one at a time, so he sued the seller, claiming that he had been cheated. Even though there was a continuity of provenance, there was little if anything of the original vehicle remaining. Similarly, the cells in your body replace themselves over a 10 year period - yet you are still recognizably and legally you.

The main themes were that both language and measurement are imprecise and there are good reasons for both, which the author does an admirable job of summarizing, particularly in Chapter 11 “When to be Vague”. Vagueness usually means less to remember and easier to verify as long as we understand the context. The “tallest house” in a small set can be quickly verified by eye, rather than measuring the 22.8 meter building. About $500 is a better estimate for a repair job than $475.50, when there may be unknown problems lurking in the plumbing, and a politician would be wise not to be over specific in her promise of what she will do in order to lower the cost to her reputation should she be unable to accomplish it. Low commitments are easier to fulfill than higher ones, and a certain degree of ambiguity can be a strategic asset - while voters may be led astray by their own assumptions, ambiguous statements allow for plausible retreat. Nor should laws or mission statements be too specific, in order to deal with future contingencies; the example used is laws against “indecency” which are flexible to local sensibilities and the times.

It's not a bad book and I may keep it to drag off the shelf and point to a chapter and say “this is what I mean – read this”, or it may wind up donated to a book sale when I need some shelf space.

[Collin Lysford · Rating 2 out of 5]

There's some genuinely interesting stuff about non-boolean logic here, but it's buried under a lot of tedious prose and endless rephrasings of the sorites paradox. This has the feel of a bunch of individual lectures packaged chapter-by-chapter into a book, with a lot of wasted effort on retreading old ground and examples that are just different enough to requiring restarting from the get-go every time. There's also a lot of catty digs towards various tribes of logicians that I just could not possibly care less about.

I think more than anything, it's important to distinguish when a book should be a scientific history vs. a modern treatise. This is sort of the worst of both worlds, in that it has all of the baggage that comes with a history but none of the payoff in terms of telling the human stories.

[André Jan · Rating 4 out of 5]

An excellent book...I just have no idea why you would out the result of a truth table in the middle under the operator.

[Rohit · Rating 3 out of 5]

Very unusual topic. Author has succeeded in some extent to convince reader about his argument about vagueness. Book starts with interesting facts and information. Examples discussed in book are very convincing but not comprehensive. Some arguments like Sorites paradox are explained excellently. I think author should have stick to one particular example from different field and should have explained them in details. Author has tried to be non technical as possible but at last topic is hard to understand without core scientific language. Hence it is advisable to read this book only if you have good knowledge of scientific systems author is talking about.

[Katja · Rating 4 out of 5]

This book is about vagueness in language, that is about expressions which allow for "grey areas", such as "tall" or "good quality". The first six chapters should be interesting for anyone curious about language use. If you know a bit about linguistics, in particular semantics, you might want to jump directly to chapter 7 and read from there on. There, the discussion is centered around the sorties paradox, and several attempts to explain it from the logic and probabilistic perspectives are reviewed.

[Justin Koch · Rating 4 out of 5]

I spent tons if time reading and rereading this book. It's the most practical philosophy book I've read and I've actually read a few. It's hard to digest, but worth the effort.

[Brian Schuster · Rating 4 out of 5]

Dryer subject matter, but an interesting, and important, subject for those interested in Natural Language processing.