Customer Reviews

Beginning Logic

5 star:		(3)
4 star:		(3)
3 star:		(2)
2 star:		(0)
1 star:		(2)

 

 

While there is currently a variety of logical systems about, Lemmon's is well balanced and fairly intuitive. His approach is to limit his formal system to a few simple rules. The advantage is that it makes his meta-logic much easier, and the reader can grasp the whole system very quickly. The downside it that the system becomes cumbersome when trying to prove more difficult problems. To help simplify the longer proofs, Lemmon provides a list of already proven theorems, which one can substitute into the proof. His approach is elegant, and in my view, successful. While the text tends to be dense, his liberal use of examples clarifies many of the finer points. Still, the reader does have to work at it so I cannot recommend this text to beginning logic students. Davis' "Introduction to Logic" is much more straightforward, and much simpler. However, for serious students of logic, with a solid analytical background, or a good foundation in mathematics, this text provides a very good logical system.

I used this book as part of an independent study of logic. It is dense, so unless you are willing to sit down and study it exhaustively or you have an experienced teacher (as I did), start with something lighter. That said, once I gained some knowledge in the area, the book was a pleasure to use, as Lemmon's precise language made it easier to clarify certain points. The largest drawback to this book is that it doesn't have solutions to its exercises, and these methods are not mechanical-you must know or learn how to make intuitive leaps or you will not be able to solve the problems. davewitt@technologist.com

This is really an awful book. The advantages are that it's relatively cheap and light, the disadvantages are everything else.

Some claim this book is great because it "doesn't introduce too many concepts" and thus makes things easier to understand. This leaves you with only the most basic tools trying to cover the most complex problems. It's a bit like saying a construction crew would be better off leaving the bulldozer at home and doing all their work with shovels and hammers, because having too much equipment might confuse them. Many tools of other systems which are very intuitive and widely accepted, such as DeMorgan's Laws or the disjunctive syllogism, have to be derived from scratch every single time. It's fine if the book wants to start out making you derive these rules, but when they are first proven, they should then be accepted for future use in the system.

The narrative style of the book is an absolute mess. The author introduces most all of the major concepts in natural English form, and the symbols and definitions of any particular tool are usually buried deep in difficult text, or in an example problem pages later if you're lucky. Any half-decent book should give you something along the lines of a short primer, show the symbols (MPP = P->Q,P |- Q), and then include a text box with the philosophical basis for that statement if such explanation is desired. Imagine instead that a long section of text mentions a variable P and an implication from that variable to another (Q) and the conclusion of this is that the consequent of the implication is entailed. Did I lose you with that last sentence? Imagine 200 pages of that.

The book also includes practice problems with no answer keys. Even if you get the teacher's guide, you only get a partial solutions list. Combined with the difficult narrative style, this book is therefore weak for self-learning. If you're going to be having a class on logic, there might as well not be a book in the class whatsoever, because the teacher is going to have to explain all the concepts for you anyway. If you do have to purchase this book for a class, please ensure that the teacher covers all material sufficiently and works through numerous examples in-class. I had a fair background in logic before starting this class, but due to the lack of tools under the Lemmon system and a limited classroom, I'm struggling to keep up with the material. I have found myself on many occasions seeing a simple solution to a problem that might take three or four steps in any system allowing you to use more advanced rules, but which under the Lemmon system could run to 20 steps. I get so mixed up when I'm inside my third wedge elimination (a truly cumbersome rule) that I can't remember what I was doing in the problem overall.

If you're a teacher looking at this book, skip it and print off your own guides. There are so few true concepts in this book that most everything you would need for a class could be fit onto a two-page sheet of terminology and the symbolic representations of the rules. And for sanity's sake, once you've shown an initial proof to motivate rules such as DeMorgan's, let the students use those rules in future problems. Artificially limiting the class to primitive tools is just asking them to jump through a hoop, it doesn't motivate deeper understanding of the concepts. Repeatedly during class students have noted how they can intuitively see a solution to a problem, but the limited rules of this system confuse them to the point that they are unable to express the arguments despite a deep comprehension of the task at hand.

Overall, I recommend against this book.

I obtained this book for a college course I am taking, Introduction to Logic. The book is well written and I think it does what it's meant to do, but it does have its flaws.

On the one hand, I believe that the book does a great job of introducing the basic of Logic and all of its symbols and syntax. It makes a great complement to my class. However, it often becomes very heady and can be hard to understand unless you are fully committed and make sure you have a grasp of one topic completely before moving on to the next.

One of my largest complaints about the book is that it provides practice problems with no answers. This means that the problems are basically worthless to me in the sense that even if I feel that I know how to do all the problems in the chapter I have no way of knowing if I truly understand the more complicated subject matter through private study.

I would still recommend this book to anyone who is genuinely interested in the subject AND has a competent mentor/teacher to guide them. If you're going it alone though, it may be a little rough.

A great book of predicate and simple quantifier logic. VERY complete, includes nice examples in English translation and in logic. It also has practice problems after each section. However, it is dense, and unless you have someone who can help clarify concepts for you, this book can become confusing and difficult. Overall, a very good logic book.

This is an older book, so it is a little wordy. The wording of explanations for rules is a bit strange, but its okay because Lemmon follows all explanations with examples.

I have got to admit, this is a very difficult book to follow. It is higher order logic--very difficult material for most people to grasp--hard for me and I tutored it. This book may have been impossible for me to learn from on my own--I bought it for use in a class, and used it with assistance from a logician. There are a few out there who will be able to learn it on their own with this book--but not many. For most, this will be torture! But if you love logic and get it, then this book will be great for you!

I read the Italian translation of this book, and it was really great experience. It helps me a lot in my daily work and is really a good book. One could expect that a new edition of this useful booklet would include the programs used for the Appendix, theorem proofs.

For those who are interested in learning the basics of propositional calculus, this is a fantastic book. It's a little difficult to understand however once you master the concepts, the text becomes much easier to read. I recomend this book to anyone interested in learning how to think.

Okay. This book is cheap which is nice. BUT it is NOT HELPFUL. Even for someone with a background in logic this book is worthless, but especially for a beginner. There are hardly any practice problems, the explanations are terrible, and for the few problems in the book there are not any answers. So, it is very difficult to use this book and know what (if anything) you are doing right or doing wrong.