Logic Flashcards Exam Questions and Answers

Logic Flashcards Exam Questions and Answers Logic - Correct Answers: The organized body of knowledge, or science, that evaluates arguments The Law of Excluded Middle - Correct Answers: Any statement is either true of false. The Law of Identity - Correct Answers: If a statement is true, then it is true. The Law of Non-contradiction - Correct Answers: A statement cannot be both true and false. Formal Logic - Correct Answers: Deals with the proper modes of reasoning Informal Logic - Correct Answers: Deals with operations of thinking that are indirectly related to reasoning. Induction - Correct Answers: Reasoning with probability from examples or experience to general rules. Deduction - Correct Answers: Reasoning with certainty from premises to conclusions. Connective - Correct Answers: An operator used in logic to combine two logical formulas. See first order logic. Pun - Correct Answers: A humorous play on words Rhetoric - Correct Answers: Study of the technique and rules for using language effectively (especially in public speaking) Axiom - Correct Answers: A universal truth; an established rule Argument - Correct Answers: A group of statements, one or more of which (the premises) are claimed to provide support for, or reasons to believe, one of the others (the conclusion). Statement - Correct Answers: A sentence that is either true or false. The purpose of Logic as a Science - Correct Answers: To develop methods and techniques that allow us to distinguish good arguments from bad. Declarative sentence - Correct Answers: A sentence that makes a statement or declaration. Truth Value - Correct Answers: The truth or falsity of a statement Premise - Correct Answers: The statements that set forth the reasons or evidence Conclusion - Correct Answers: The statement that the evidence is claimed to support or imply. What is one of the most important tasks in the analysis of arguments? - Correct Answers: Being able to distinguish premises from conclusions Conclusion indicators - Correct Answers: Words or phrases that frequently alert the reader (or listener) that the conclusion is being given. Examples include "therefore"; "thus"; "hence"; "it follows that"; "we may infer that"; "so"; and "we may conclude that". Premise indicators - Correct Answers: words or phrases that frequently alert the reader (or listener) that a premise is being given. Examples include "because"; "since"; "for"; "for example"; "for the reason that"; "in that"; "given that"; "as indicated by"; "due to"; "owing to"; "this can be seen from"; "we know this by". What do you do when an argument contains no indicators? - Correct Answers: Ask youreslf questions. Examples include "What single statement is claimed (implicitly) to follow from the others?"; "What is the arguer trying to prove?"; "What is the main point in the passage"? What is the pattern found in most arguments that lack indicator words? - Correct Answers: The intended conclusion is stated first, and the remaining statements are then offered in support of this first statement. When an argument is restructured according to logical principles, the conclusion is always listed where? - Correct Answers: After the premises. How should arguments be restructured? - Correct Answers: They should remain as close as possible to the original version, while at the same time attending to the requirement that premises and conclusion be complete sentences that are meaningful in the order in which they are listed. Inference - Correct Answers: The reasoning process expressed by an argument. Proposition - Correct Answers: The meaning or information content of a statement. Who is the father of logic? - Correct Answers: Aristotle (384-322 B.C.) Syllogistic Logic - Correct Answers: A kind of logic in which the fundamental elements are terms, and arguments are evaluated as good or bad depending on how the terms are arranged in the argument. If A = B & B = C, then A = C Modal logic - Correct Answers: A kind of logic that involves such concepts as possibility, ne- cessity, belief, and doubt. Who helped found the Stoic school & developed a logic in which the fundamental elements were whole propositions? - Correct Answers: Chrysippus (279-206 B.C.) Who developed the theory of the compound categorical syllogism? - Correct Answers: The physician Galen (A.D. 129-ca. 199) Who was the first major logician of the Middle Ages? - Correct Answers: Peter Abelard () What are Peter Abelard's major accomplishments? - Correct Answers: He reconstructed and refined the logic of Aristotle and Chrysippus, originated a theory of universals and distinguished arguments that are valid because of their form from those that are valid because of their content. What was Peter Abelard's theory of universals? - Correct Answers: It traced the universal character of general terms to concepts in the mind rather than to "natures" existing outside the mind, as Aristotle had held. What became the standard textbook in logic for three hundred years? - Correct Answers: Summulae Logicales Author, Peter of Spain (ca. ) Who extended the theory of modal logic, conducted an exhaustive study of the forms of valid and invalid syllogisms, and further developed the idea of a metalanguage? - Correct Answers: William of Ockham (ca. ) What is metalanguage? - Correct Answers: A higher-level language used to discuss linguistic entities such as words, terms, and propositions. Who is sometimes credited with being the father of symbolic logic? - Correct Answers: Gottfried Wilhelm Leibniz () Who laid the foundations of modern mathemati- cal logic? - Correct Answers: Gottlob Frege () Who wrote the Principia Mathematica? - Correct Answers: Alfred North Whitehead () Bertrand Russell () Who's famous theorem stated that in any formal system adequate for number theory there exists an undecidable formula—that is, a formula such that neither it nor its negation is derivable from the axioms of the system? - Correct Answers: Kurt Goedel () A passage contains an argument if it purports to prove something if what? - Correct Answers: It purports to prove something. What are the 2 conditions that must be fulfilled for a passage to purport to prove something? - Correct Answers: 1. At least one of the statements must claim to present evidence or reasons. 2. There must be a claim that the alleged evidence or reasons supports or implies something—that is, a claim that something follows from the alleged evidence. Factual claim - Correct Answers: A claim to based on evidence or reasons., a claim that something is true; a claim that evidence or reasons are being presented Inferential claim - Correct Answers: A claim that alleged evidence or reasons support or imply something Explicit inferential claim - Correct Answers: Usually asserted by premise or conclusion indicator words ("thus," "since," "because," "hence," "therefore," and so on) Implicit inferential claim - Correct Answers: Exists if there is an inferential relationship between the statements in a passage, but the passage contains no indicator words In deciding whether there is a claim that evidence supports or implies something, keep an eye out for what 2 things? - Correct Answers: Indicator words and the presence of an inferential relationship between the statements. Inferential relationship - Correct Answers: A relationship is presumed, but it is a relationship that deals with degrees of influence of one variable on another What is a good mental aid to detect the occurrence of an inferential relationship between the statements in a passage? - Correct Answers: Insert the word "therefore" before the various statements to see whether it makes sense to interpret one of them as following from the others. Simple noninferential passages - Correct Answers: Unproblematic passages that lack a claim that anything is being proved; warning, piece of advice, statement of belief or opinion, report, illustration, explanation, conditional statement A warning - Correct Answers: A form of expression that is intended to put someone on guard against a dangerous or detrimental situation. A piece of advice - Correct Answers: A form of expression that makes a recommendation about some future decision or course of conduct. A statement of belief or opinion - Correct Answers: An expression about what someone happens to believe or think about something. Loosely associated statements - Correct Answers: May be about the same general subject, but they lack a claim that one of them is proved by the others. A report - Correct Answers: Consists of a group of statements that convey information about some topic or event. Expository passage - Correct Answers: A kind of discourse that begins with a topic sentence fol- lowed by one or more sentences that develop the topic sentence. Topic sentence - Correct Answers: A sentence that states the topic of its paragraph simple non-inferential passages - Correct Answers: unproblematic passages that lack a claim that anything is being proved; warning, piece of advice, statement of belief or opinion, report, illustration, explanation, conditional statement How to decide whether an expository passage should be interpreted as an argument? - Correct Answers: try to determine whether the purpose of the subsequent sentences in the passage is merely to develop the topic sentence or also to prove it. In borderline cases, ask your- self whether the topic sentence makes a claim that everyone accepts or agrees with. If it does, the passage is probably not an argument. An illustration - Correct Answers: consists of a statement about a certain subject combined with a reference to one or more specific instances intended to show what something means or how it is done. Illustrations are often confused with arguments because many of them contain indicator words such as "thus." Arguments from example - Correct Answers: an argument that purports to prove something by giving one or more examples of it How to decide whether an illustration should be interpreted as an argument? - Correct Answers: one must determine whether the passage merely shows how something is done or what something means, or whether it also purports to prove something. An explanation - Correct Answers: a group of statements that purports to shed light on some event or phenomenon. Explanandum - Correct Answers: the statement that describes the event or phenomenon to be explained Explanans - Correct Answers: the statement or group of statements that purports to do the explaining Why are explanations not arguments? - Correct Answers: because in an explanation the purpose of the explanans is to shed light on, or to make sense of, the explanandum event—not to prove that it occurred. In other words, the purpose of the explanans is to show why something is the case, while in an argument, the purpose of the premises is to prove that something is the case. How does one distinguish explanations from arguments? - Correct Answers: identify the statement that is either the explanandum or the conclusion (usually this is the statement that precedes the word "because"). If this statement describes an accepted matter of fact, and if the remaining statements purport to shed light on this statement, then the passage is an explanation. Conditional statement - Correct Answers: a type of logical statement that has two parts, a hypothesis and a conclusion. an if-then statement. Every conditional statement is made up of two component statements. The component statement immediately following the "if " is called the antecedent, and the one following the "then" is called the consequent. antecedent - Correct Answers: a preceding occurrence or cause or event consequent - Correct Answers: The result of the condition, the part after the "then" The relation between conditional statements and arguments may now be summarized as what? - Correct Answers: 1. A single conditional statement is not an argument. 2. A conditional statement may serve as either the premise or the conclusion (or both) of an argument. 3. The inferential content of a conditional statement may be reexpressed to form an argument. deductive argument - Correct Answers: an argument incorporating the claim that it is impossible for the conclusion to be false given that the premises are true. inductive argument - Correct Answers: an argument incorporating the claim that it is IMPROBABLE that the conclusion be false given that the premises are true argument based on mathematics - Correct Answers: is an argument in which the conclusion depends on some purely arithmetic or geometric computation or measurement. argument from definition - Correct Answers: is an argument in which the conclusion is claimed to depend merely upon the definition of some word or phrase used in the premise or conclusion. categorical syllogism - Correct Answers: is a syllogism in which each statement begins with one of the words "all," "no," or "some." hypothetical syllogism - Correct Answers: is a syllogism having a conditional statement for one or both of its premises. disjunctive syllogism - Correct Answers: is a syllogism having a disjunctive statement (i.e., an "either . . . or . . ." statement) for one of its premises. (Inductive Argument Forms) prediction - Correct Answers: is an argument that proceeds from our knowledge of the past to a claim about the future. argument from analogy - Correct Answers: is an argument that depends on the existence of an analogy, or similarity, between two things or states of affairs. generalization - Correct Answers: is an argument that proceeds from the knowledge of a selected sample to some claim about the whole group. argument from authority - Correct Answers: is an argument that concludes something is true because a presumed expert or witness has said that it is. argument based on signs - Correct Answers: is an argument that proceeds from the knowledge of a sign to a claim about the thing or situation that the sign symbolizes. causal inference - Correct Answers: is an argument that proceeds from knowledge of a cause to a claim about an effect, or, conversely, from knowledge of an effect to a claim about a cause. particular statement - Correct Answers: is one that makes a claim about one or more particular members of a class. general statement - Correct Answers: is one that makes a claim about all the members of a class. valid deductive argument - Correct Answers: is an argument in which it is impossible for the conclusion to be false given that the premises are true. invalid deductive argument - Correct Answers: is a deductive argument in which it is possible for the conclusion to be false given that the premises are true. sound argument - Correct Answers: is a deductive argument that is valid and has all true premises. strong inductive argument - Correct Answers: is an inductive argument in which it is improbable that the conclusion be false given that the premises are true. weak inductive argument - Correct Answers: is an argument in which the conclusion does not follow probably from the premises, even though it is claimed to. cogent argument - Correct Answers: is an inductive argument that is strong and has all true premises; if either condition is missing, the argument is uncogent. substitution instance - Correct Answers: Any argument that is produced by uniformly substituting terms or statements in place of the letters in an argument form. counterexample method - Correct Answers: A substitution instance having true premises and a false conclusion (like the cats-and- dogs example just constructed) is called a counterexample, and the method we have just used to prove the romantic-novels argument invalid.