Logic

It is used for personal reasons.

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Terrific introduction to the subject, a little dated but valuable for anyone who sees a need for clear critical thinking.

I love it

... A must have, as a very good introduction to predicate logic & first-order logic.Also, Hodges does a excellent job on Tableaux...As a complement : "Elementary logic" by Quine.

Hodges, please get a second edition of this wonderful book back into print!!This is probably the best intro there is to modern logic for people without prior training in science and math. The examples are all taken form linguistics and philosophy. Ironically, the author is also a high power mathematician, but he does not let that show. This is the book Quine should have written instead of his Elementary Logic. Also clearer and less threatening to sanity than Spencer Brown's Laws of Form.

A solid presentation of elementary logic.

Logic, therefore, as the science thought, or the science of the process of pure reason, should be capable of being constructed a priori."-Arthur Schopenhauer, The Art of Controversy("a priori" is defined as deduced from self-evident premises)I am going to explain to you exactly why this book 'Logic: an introduction to elementary logic' by Wilfred Hodges is an obvious example of the deliberate suppression and subversion of the science of Logic. Before I can do that however, I must offer you this definition. It happens to be one of the most clear, concise and useful a priori definitions of logic that I have found."Fallacious reasoning is just the opposite of what can be called cogent reasoning. We reason cogently when we reason (1) validly; (2) from premises well supported by evidence; and (3) using all relevant evidence we know of. The purpose of avoiding fallacious reasoning is, of course, to increase our chances of reasoning cogently."-Howard Kahane, Logic and Contemporary Rhetoric, 1976, second editionHere's the problem with Hodges' book; he never explains two out of three of these a priori essential elements of logic to his reader. That's right; no explaination that premises must be supported by evidence, or that a logical argument must contain all of the known relevant evidence (or the logical fallacy of suppressed evidence).Why do you suppose that is?Here's what he does explain:(1) Logical arguments begin from true premises.(2) Logical arguments begin from premises and come to conclusions which are free of obvious contradiction.Here's the problem; the human mind already does that instinctively, and Hodges knows it. I don't know of a single person who would believe an argument that comes from premises which they know are false, or which contains obvious contradiction. Where we usually fail is in our tendency to allow ourselves to be manipulated through authority and emotion, and our tendency to trust those who have manipulated us. In short, when we are presented with an argument by authority figures that seems plausible, we don't tend to insist upon solid verifiable supporting evidence, or try to seek out the best arguments and evidence which opposes it.Historically speaking, the horrible loss of life, liberty, and resources that have been made possible through this inherent flaw in our psychological makeup can't be overstated. And Hodges has written a book about logic that leaves his readers just as ignorant and easily manipulated as they ever were.Here's a bit of information about the importance of supporting evidence and the suppression of relevant evidence that may be helpful.(A) "Aristotle devides all conclusions into logical and dialectical, in the manner described, and then into eristical. (3) Eristic is the method by which the form of the conclusion is correct, but the premises, the material from which it is drawn, are not true, but only appear to be true. Finally (4) sophistic is the method in which the form of the conclusion is false, although it seems correct. These three last properly belong to the art of Controversial Dialectic, as they have no objective truth in view, but only the appearance of it, and pay no regard to truth itself; that is to say, they aim at victory."-Arthur Schopenhauer, The Art of Controversy(B) "All instruction given or received by way of argument proceeds from pre-existent knowledge."-Aristotle, Posterior Analytics(C) "We ought in fairness to fight our case with no help beyond the bare facts: nothing, therefore, should matter except the proof of those facts."-Aristotle, Rhetoric(D) "The truth or falsity of a statement depends on facts, not on any power on the part of the statement itself of admitting contrary qualities". - Aristotle, Categories(E) "Similarly with any other art or science. Consequently, if the attributes of the thing are apprehended, our business will then be to exhibit readily the demonstration. For if none of the true attributes of things had been omitted in the historical survey, we should be able to discover the proof and demonstrate everything which admitted of proof, and to make that clear , whose nature does not admit of proof". - Aristotle, Prior Analytics(F) "We suppose ourselves to posses unqualified scientific knowledge of a thing, as opposed to knowing it in the accidental way in which the sophist knows, when we think that we know the cause on which the fact depends, as the cause of that fact and of no other, and further, that the fact could not be other than it is". - Aristotle, Posterior Analytics(G) "The province of Logic must be restricted to that portion of our knowledge which consists of inferences from truths previously known; whether those antecedent data be general propositions, or particular observations and perceptions. Logic is not the science of Belief, but the science of Proof, or Evidence. In so far as belief professes to be founded on proof, the office of Logic is to supply a test for ascertaining whether or not the belief is well grounded."- John Stuart Mill, A System of Logic(H) "The statements that make up an argument are divided into one or more premises and one and only one conclusion. The premises are the statements that set forth the evidence, and the conclusion is the statement that is claimed to follow from the evidence."-Patrick Hurley, A Concise Introduction to Logic (1985)(I) "An argument expresses an inference in a special way, in terms of one or more premises that present evidence and a conclusion that is claimed to follow from that evidence. Because the antecedent of a conditional statement is not asserted to be true, it presents no evidence; and because it presents no evidence, a conditional statement is not an argument, even though it may express an inference."-Patrick Hurley, A Concise Introduction to Logic (1985)(J) "The fallacy of suppressed evidence is committed when an arguer ignores evidence that would tend to undermine the premises of an otherwise good argument, causing it to be unsound or uncogent. Suppressed evidence is a fallacy of presumption and is closely related to begging the question. As such, it's occurrence does not affect the relationship between premises and conclusion but rather the alleged truth of premises. The fallacy consists in passing off what are at best half-truths as if they were whole truths, thus making what is actually a defective argument appear to be good. The fallacy is especially common among arguers who have a vested interest in the situation to which the argument pertains."-Patrick Hurley, A Concise Introduction to Logic (1985)(K) "Fallacious Even If ValidSo far, we have considered arguments that are fallacious precisely because they are invalid. But arguments may be fallacious for reasons other invalidity --even valid arguments may be fallacious. Thus we have the fallacy category 'fallacious even if valid.1. Suppressed EvidenceWhen arguing, it is human nature to present every reason you can think of that is favorable to your own position, while omitting those that are unfavorable. Nevertheless, anyone who argues in this very human way argues fallaciously. Let's call this the fallacy of 'suppressed evidence...Questionable PremiseThe fallacy of the 'questionable premise' is simply the fallacy of accepting premises in an argument that are both questionable and inadequately supported."-Howard Kahane, Logic and Contemporary Rhetoric, 1976" ' How is the dictionary getting on?' Said Whinston, raising his voice to overcome the noise.'Slowly,' said Syme. "I'm on the abjectives. It's fascinating.'He had brightened up immediately at the mention of Newspeak ...'The Eleventh Edition is the definitive edition,' he said. ' We're getting the language into its final shape -- the shape it's going to have when nobody speaks anything else. When we've finished with it, people like you will have to learn it all over again. You think, I dare say, that our chief job is inventing new words. But not a bit of it! We're destroying words -- scores of them, hundreds of them, every day. We're cutting the language down to the bone. The Eleventh Edition won't contain a singe word that will become obsolete before the year 2050 ...'It's a beautiful thing, the destruction of words' ...'Don't you see that the whole aim of Newspeak is to narrow the range of thought? In the end we shall make thoughtcrime literally impossible, because there will be no words in which to express it.' "- George Orwell, 1984"From the proletarians nothing is to be feared. Left to themselves, they will continue from generation to generation and from century to century, working, breeding, and dying, not only without any impulse to rebel, but without the power of grasping that the world could be other than it is. They could only be dangerous if the advance of industrial technique made it necessary to educate them more highly; but, since military and commercial rivalry are no longer important, the level of popular education is actually declining. What opinions the masses hold, or do not hold, is looked upon as a matter of indifference. They can be granted intellectual liberty because they have no intellect."-George Orwell, 1984

If you want to know about logic, this is the book, Excellent desriptions, full of examples and clear and consise explanations. A must have if you're studying philosophy, you'll learn it in a matter of hours with this book.

Great buy. As a used book it was in very good condition

There are a lot of books about logic but, in essence, all of them say the same. This book is different because it tries to show logic fresher and connected with your normal live. A good introduction, in short.

Very simple to read, and a perfect start into Logic. I liked very much. Very accesible to the topic, and easy to understand

I found this to be a good introduction to Logic and also as a recap. It will not be an easy read for the complete beginner, after the first couple of chapters, but I still feel that it may be quite accessible with some thought. I prefer the introduction to logic by E J Lemmon but I think that is long out of print.