or
Sign in to turn on 1-Click ordering.
More Buying Choices
Have one to sell? Sell yours here
Sorry, this item is not available in
Image not available for
Colour:
Image not available

 
Tell the Publisher!
Id like to read this book on Kindle

Don't have a Kindle? Get your Kindle here, or download a FREE Kindle Reading App.

Computers Ltd: What They REALLY Can't Do (Oxford Paperbacks) [Paperback]

David Harel
3.8 out of 5 stars  See all reviews (4 customer reviews)
Price: 12.99 & FREE Delivery in the UK. Details
o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o
In stock.
Dispatched from and sold by Amazon. Gift-wrap available.
Want it tomorrow, 11 July? Choose Express delivery at checkout. Details

Formats

Amazon Price New from Used from
Hardcover --  
Paperback 12.99  

Book Description

25 Sep 2003 Oxford Paperbacks
Computers are incredible. They are one of the most important inventions of the 20th century, dramatically and irrevocably changing the way we live. That is the good news. The bad news is that there are still major limitations to computers, serious problems that not even the most powerful computers can solve. The consequences of such limitations can be serious. Too often these limits get overlooked, in the quest for bigger, better, and more powerful computers. In Computers Ltd., David Harel, best-selling author of Algorithmics, explains and illustrates one of the most fundamental, yet under-exposed facets of computers - their inherent limitations. Looking at the bad news that is proven, lasting and robust, discussing limitations that no amounts of hardware, software, talents or resources can overcome, the book presents a disturbing and provocative view of computing at the start of the 21st century. Along the way he shows just how far from perfect computers are, while shattering some of the many claims made for these machines. Though we may strive for bigger and better things in computing, we need to be realistic: computers are not omnipotent - far from it. Moreover, the problem is real and here to stay.

Special Offers and Product Promotions

  • Spend 30 and get Norton 360 21.0 - 3 Computers, 1 Year 2014 for 24.99. Here's how (terms and conditions apply)

Frequently Bought Together

Computers Ltd: What They REALLY Can't Do (Oxford Paperbacks) + New Turing Omnibus
Buy the selected items together
  • New Turing Omnibus 16.48


Product details

  • Paperback: 242 pages
  • Publisher: OUP Oxford; New Ed edition (25 Sep 2003)
  • Language: English
  • ISBN-10: 0198604424
  • ISBN-13: 978-0198604426
  • Product Dimensions: 2 x 12.5 x 19 cm
  • Average Customer Review: 3.8 out of 5 stars  See all reviews (4 customer reviews)
  • Amazon Bestsellers Rank: 337,496 in Books (See Top 100 in Books)
  • See Complete Table of Contents

More About the Author

Discover books, learn about writers, and more.

Product Description

Review

Computers Ltd is a gripping book Cern Courier a clear and friendly book The Guardian Review from previous edition This book is a veritable tour de force. Harel writes with uncommon verve, clarity, and imagination ... This is science writing at its best. Times Higher Education Supplement This is the book I would most like to have written. Prof. Darrell Ince, Open University Thank heavens ... for David Harel's book on the theoretical limitations of computers ... the insights Computers Ltd. provides are of an unusually enduring and worthwhile nature. The Economist, 30 Sept. 2000 The best short introduction to the things that computers can, can't, might, and could, eventually, do. John D. Barrow, Professor of Mathematical Sciences, Cambridge University, and author of 'Impossibility' and the forthcoming 'Book of Nothing' An enlightening and entertaining explanation, written by a profound computer scientist and master expositor. A must read for inquisitive minds. Michael Rabin, Professor of Computer Science, Harvard University

About the Author

David Harel is the Dean of the Faculty of Mathematics and Computer Science at the Weizmann Institute of Science in Israel, and is incumbent of the William Sussman Professional Chair. He is a highly respected computer scientist who has carried out research in many areas of computer science. He has received a number of awards, including ACM's Karlstrom Outstanding Educator Award in 1992, and the 1997 Israeli Prime Minister's Award for Software. His book, Algorithmics: The Spirit of Computing (Addison-Wesley, 1987, 2nd. edn. 1992) was the Spring 1988 Main Selection of the Macmillan Library of Science. He is a Fellow of the AMC and of the IEEE.

Inside This Book (Learn More)
First Sentence
Computers are amazing. Read the first page
Explore More
Concordance
Browse Sample Pages
Front Cover | Copyright | Table of Contents | Excerpt | Index | Back Cover
Search inside this book:

Sell a Digital Version of This Book in the Kindle Store

If you are a publisher or author and hold the digital rights to a book, you can sell a digital version of it in our Kindle Store. Learn more

What Other Items Do Customers Buy After Viewing This Item?


Customer Reviews

3.8 out of 5 stars
3.8 out of 5 stars
Most Helpful Customer Reviews
5 of 5 people found the following review helpful
Format:Hardcover
This another nice book from David Harel, the author of the delightful
'Algorithmics : the spirit of Computer Science', which introduces the
general reader to the limits of computation (and hence the limits of
what computers can do).
Harel, who's a renowned figure in the field of Theoretical Computer Science,
has the ability to write and explain in a way that makes things seem
wonderfully clear, and indeed it is only such authors who can write good
books for the general reader.
This small (240 pages) book is quite ambitious in its coverage of topics -
starting off with the notion of an algorithm, it goes on to discuss
Efficiency and correctness, Turing machines, Finite state machines,
Decidability, Computability, Complexity, NP-completeness, Recursion,
Parallel algorithms, Probabilistic algorithms, and even touches upon
Quantum Computing and Artificial Intelligence !!
All this is done with almost no mathematics, at least hardly any beyond
high-school level. The reader is gently introduced to some of the most
celebrated problems of Computer Science, and he/she can get a feel of
the nature of this exciting and interesting field.
Throughout the book, the author keeps underscoring the fact that no matter
how far technology progresses, there'll always be problems that we can't
solve cheaply, or can't solve at all, or can't ever know whether they
can be solved or not (!!), ie he stresses that there are problems that
are 'beyond computers', which cannot be tamed by more and more processing
power or any other technological advancements.
Read more ›
Comment | 
Was this review helpful to you?
1 of 1 people found the following review helpful
3.0 out of 5 stars Interesting but repetitive 28 Jan 2001
By James M
Format:Hardcover
Harel presented an interesting case against computers, but he just seemed to be driving one or two points home too much. Yes, we KNOW computers are serial and that some tasks take ages. Yet it the current paradigm of computing is rapidly shifting (parallel, quantum, molecular...) and while he does briefly address these, I don't think enough emphasis is given to quite how important non-computable issues are. At the moment, cryptography is non-computable (well, not true - but very hard) and quantum computing will theoritically destroy that...etc.
I don't mean to dismiss this book - it does have some very interesting points, thoughts and ideas and the title of the books obviously suggests that it should look at the BAD points of computers as opposed to the good, but a more open approach could have been taken.
Comment | 
Was this review helpful to you?
5.0 out of 5 stars Great non-technical introduction 29 Jun 2011
Format:Paperback
The book is a very well-written and clearly presented introduction to the limits of computation and the fundamental open problems in the field. It requires hardly any mathematical knowledge to follow, although some familiarity with the basic notions of the theory of computation would certainly make some parts of it more understandable. It also contains many references to selected works that helped shape the field of computation to its present form, making the read enjoyable even for those who would prefer more rigor in the statements made and also some proofs. However, the book is written for a general audience and thus it focuses more on intuitive explanations and gives a high-level view of the problems. It is a highly enjoyable, thought-provoking read.
Comment | 
Was this review helpful to you?
1 of 7 people found the following review helpful
Format:Paperback
Does the author have a vendetta against computers or something? The first few chapters slag off computers a great deal saying they can't do this, or they can't do that. Just because you can't work out the answer for something yourself (albeit a human) doesn't mean you can pass it off as being a computer problem/ error, but put more precisely something 'They really can't do' (as the title states). Some of the points made in the book will never be solved by a human let alone a computer.
But the book does make you think, and opens your mind to various other topics that you would never really bring into consideration when thinking about computers.
Comment | 
Was this review helpful to you?
Most Helpful Customer Reviews on Amazon.com (beta)
Amazon.com: 4.6 out of 5 stars  5 reviews
34 of 35 people found the following review helpful
4.0 out of 5 stars A limited introduction to the limits of Computation 9 Nov 2001
By Optimistix - Published on Amazon.com
Format:Hardcover
This another nice book from David Harel, the author of the delightful
'Algorithmics : the spirit of Computer Science', which introduces the
general reader to the limits of computation (and hence the limits of
what computers can do).
Harel, who's a renowned figure in the field of Theoretical Computer Science,
has the ability to write and explain in a way that makes things seem
wonderfully clear, and indeed it is only such authors who can write good
books for the general reader.
This small (240 pages) book is quite ambitious in its coverage of topics -
starting off with the notion of an algorithm, it goes on to discuss
Efficiency and correctness, Turing machines, Finite state machines,
Decidability, Computability, Complexity, NP-completeness, Recursion,
Parallel algorithms, Probabilistic algorithms, and even touches upon
Quantum Computing and Artificial Intelligence !!
All this is done with almost no mathematics, at least hardly any beyond
high-school level. The reader is gently introduced to some of the most
celebrated problems of Computer Science, and he/she can get a feel of
the nature of this exciting and interesting field.
Throughout the book, the author keeps underscoring the fact that no matter
how far technology progresses, there'll always be problems that we can't
solve cheaply, or can't solve at all, or can't ever know whether they
can be solved or not (!!), ie he stresses that there are problems that
are 'beyond computers', which cannot be tamed by more and more processing
power or any other technological advancements.
This book covers pretty much the same range of topics as Harel's earlier
book, 'Algorithmics : the spirit of Computer Science', but in only half
the number of pages, and with a heavy emphasis on the 'limitations' of
computers, which actually are limitations of our knowledge rather than
of the machines themselves.
How does it compare with the eariler book ? Well, it's more uptodate,
since it was published in 2000, whereas the other one was in 1992 -
so here you find buzzwords like 'Java', 'Dotcom', 'Quantum Computing',
etc, which you wouldn't find in the earlier book, but on the whole
i prefer the earlier one, since it had a little more detail, made you
think a little more, and even had exercises for those who were interested
in probing further.
So all in all, if you want a light, breezy introduction to the basic ideas
of Theoretical Computer Science which doesn't demand too much concentration,
this is a good choice, but if you're willing to put in some time & effort
& enjoy puzzles & logical thinking, then you'll find Harel's other book,
'Algorithmics : the spirit of Computer Science' much more rewarding.
2 of 2 people found the following review helpful
4.0 out of 5 stars Easy introduction 21 Sep 2004
By William Rockwell - Published on Amazon.com
Format:Hardcover|Verified Purchase
The is a good introductory book into the limits of computation. The book introduces the major concepts and vocabulary in a very easy to understand way. However that is the limit to this book on limits. If you are looking for non-technical information, then this may well be the book for you.

If you are looking for proofs, answers to your homwork problems, or rigor, you will be disappointed. The author states many conjectures few have proofs. From the conjectures he uses easily understood arguments to make his points. The conjectors are in fact true, but you will have to look elsewhere to find proofs.

The reasons I gave 4 stars instead of 5 are twofold. Although the book is pretty good, the writing seems a bit quirky at times. I would have liked to have seen a bit more rigor. Although I can understand wanting the book to be as simple as possible, but many of the proofs are not very difficult and could have been included (for example the halting problem).
5.0 out of 5 stars Not all problems are soluble via computation 2 April 2011
By Wikileaker - Published on Amazon.com
Format:Paperback
The January 1990 AT&T telephone network crash and the June 1996 inflight explosion of an Ariane 5 rocket were caused by software failures. These two citations by Harel are two examples of incorrect computer programming that should have been avoidable. With our industrial economy relying to an ever-greater extent on computers for essential functions, the importance of software reliability stands in stark relief.

Harel's third example, that of a 107 year old woman who was mailed registration paperwork for first grade, highlights that even our system of social organization is being dependent on competently run computer networks. Now, this may not be so dramatic as network or rocket crashes, but multiplied by our burgeoning population, it illustrates the fiscal nibbling that computer errors exact on our public budgets.

Thus Harel, having established the stakes (not at the outset, unfortunately, but near the end of Chapter 1), takes up the technical issues having to do with correctness of computation. The book begins with a discussion of the algorithm: the program, inputs, instances, programming languages, and termination. Then in the next chapters he goes on to problems that, even theoretically, defy solution by any means. He describes the Church-Turing Thesis having to do with "effective computability", and the Halting Problem and Rice's Theorem, "No algorithm can decide any nontrivial property of computations.

Even the problems that are solvable in theory just take too much time or machine resources to be economically worthwhile. These are the subject of Ch. 3. Chapter 4 has to do with NP-complete problems: decidable but not known to be tractable (worthwhile). In other words, you know that you can know, but you don't know!

Ch. 5 takes up algorithmic parallelism (mainly), which offers hope. Also touches on randomization, quantum computing, and molecular computing. Ch. 6 takes up cryptography, leading up to the RSA algorithm, and the zero knowledge proofs.
The last chapter takes up the notion of "artificial intelligence", the Turing test, Eliza, searching strategies, etc.

It also touches on issues not unlike those demonstrated by the recent IBM Watson project: "The difficulty is rooted in the observation that human knowledge does not consist merely of a large collection of facts. It is not only the sheer number and volume of facts that is overwhelming...but, to a much larger extent, their interrelationships and dynamics...a human's knowledge base is incredibly complex, and works in ways that are still far beyond our comprehension." Fact is, even now, after Watson, we STILL don't understand how a human knowledge base works, because Watson is not a human and does not employ human search strategies. Despite the media hype that IBM has been trying to work up on the Sunday morning news shows, Watson is still just a souped-up search engine with an English-language front end. Interesting and potentially useful, but no breakthrough.

Seems funny, or perhaps not, that this topic is taken up in the same chapter discussing the Turing test. Watson may produce results competitive with those of humans, but it works in a completely different way -- machine learning. Which means, basically, it is still a rules-based system, but it makes up new rules and modified rules as it operates. Human cognitive machinery is not rules-based. Turing says you can ignore the underlying mechanism; the only way you have to compare a human and a machine is by the results alone. It is a computer equivilant to the behaviorist perspective in psychology: all that matters is what you can see in front of you. Again, nothing new here, this has been apparent since the days of Eliza.

The book is rather theory-oriented but still educational. When Harel cited those three real-world instances I thought the text would be more practically oriented; on this score I was disappointed. But still it's a worthwhile read.
5.0 out of 5 stars What They Really Can't Do 1 April 2011
By Larry Battle - Published on Amazon.com
Format:Paperback
This book sets the record straight. Computers can't fix all of the world problems because they're limited by time and space.

The author starts off by defining algorithms and how computer programs work. He's then explores common problems in computer science using a fair amount of algebra and graphs, like NP complete problems, the travelling salesman problem, the Turing test, tower of Hanoi, and etc.

Restraining from being a complete pessimist, discussions mainly addressing Cryptography are included. Cryptography shows how computational complexity can be used for the greater good, as it's nearly impossible to break the encryption within a reasonable amount of time for any data encoded in RSA.

Lastly, the author ends the book with his take on hot areas in computing, such as Quantum Computers, Artificial Intelligence and evolutionary (generic) programming.
Overall, I enjoyed this pocket size book and recommend it for those interested in expanding their knowledge in Computer Science.
4 of 10 people found the following review helpful
5.0 out of 5 stars Popularization At Its Best 22 Nov 2000
By A Customer - Published on Amazon.com
Format:Hardcover|Verified Purchase
This book is a masterpiece! It can be read on many levels and should be a must for anyone who knows how to read and think. The layman will get a gripping and very accessible account of the limits of computing in particular, and the boundaries of knowledge in general. The professional will be able to see, in a nutshell, and explicitly, what he or she or it already knew, but did not really FEEL. But note that this book does not put down computers, but shows the intrinsic limitation of all knowledge. It should have been subtitled: `What EVEN computers can't do'.
Were these reviews helpful?   Let us know
Search Customer Reviews
Only search this product's reviews

Customer Discussions

This product's forum
Discussion Replies Latest Post
No discussions yet

Ask questions, Share opinions, Gain insight
Start a new discussion
Topic:
First post:
Prompts for sign-in
 

Search Customer Discussions
Search all Amazon discussions
   


Look for similar items by category


Feedback