Tutorial A03: Patterns of Valid Arguments By: Jonathan Chan


 Shannon Douglas
 11 months ago
 Views:
Transcription
1 A03.1 Introduction Tutorial A03: Patterns of Valid Arguments By: With valid arguments, it is impossible to have a false conclusion if the premises are all true. Obviously valid arguments play a very important role in reasoning, because if we start with true assumptions, and use only valid arguments to establish new conclusions, then our conclusions must also be true. But which are the rules we should use to decide whether an argument is valid or not? This is where formal logic comes in. By using special symbols we can describe patterns of valid argument, and formulate rules for evaluating the validity of an argument. A03.2 Modus ponens Consider the following arguments: If this object is made of copper, it will conduct electricity. This object is made of copper, so it will conduct electricity. If there is no largest prime number, then is not the largest prime number. There is no largest prime number. Therefore is not the largest prime number. If Lam is a Buddhist then he should not eat pork. Lam is a Buddhist. Therefore Lam should not eat pork. These three arguments are of course valid. Furthermore you probably notice that they are very similar to each other. What is common between them is that they have the same structure or form: Modus ponens  If P then Q. P. Therefore Q. Here, the letters P and Q are called sentence letters. They are used to translate or represent statements. By replacing P and Q with appropriate sentences, we can generate the original three valid arguments. This shows that the three arguments have a common form. It is also in virtue of this form that the arguments are valid, for we can see that any argument of the same form is a valid argument. Because this particular pattern of argument is quite common, it has been given a name. It is known as modus ponens. However, don't confuse modus ponens with the following form of argument, which is not valid! Affirming the consequent  If P then Q. Q. Therefore, P. Note  When we say that this is not a valid pattern of argument, what is meant is that not every argument of this pattern is valid. This is different from saying that every argument of this pattern is not valid. See if you can figure out why this is the case. Giving arguments of this form is a fallacy  making a mistake of reasoning. This particular mistake is known as affirming the consequent.
2 If Jane lives in London then Jane lives in England. Jane lives in England. Therefore Jane lives in London. [Not valid  perhaps Jane lives in Liverpool.] If Bing has gone shopping then Daniel will be unhappy. Daniel is unhappy. So Bing has gone shopping. [Not valid  perhaps Daniel is unhappy because he has run out of vodka to drink.] There are of course many other patterns of valid argument. Now we shall introduce a few more patterns which are often used in reasoning. A03.3 Modus tollens Modus tollens  If P then Q. NotQ. Therefore, notp. Here, "notq" simply means the denial of Q. So if Q means "Today is hot.", then "notq" can be used to translate "It is not the case that today is hot", or "Today is not hot." If Betty is on the plane, she will be in the A1 seat. But Betty is not in the A1 seat. So she is not on the plane. But do distinguish modus tollens from the following fallacious pattern of argument : Denying the antecedent  If P then Q, notp. Therefore, notq. If Elsie is competent, she will get an important job. But Elsie is not competent. So she will not get an important job. [Not valid : Perhaps Elsie is incompetent but her boss likes her because she accepts very low wages.] A03.4 Hypothetical syllogism If P then Q, If Q then R. Therefore, if P then R. If God created the universe then the universe will be perfect. If the universe is perfect then there will be no evil. So if God created the universe there will be no evil. A03.5 Disjunctive syllogism P or Q. NotP. Therefore, Q ; P or Q, NotQ. Therefore, P. Either the government brings about more sensible educational reforms, or the only good schools left will be private ones for rich kids. The government is not going to carry out sensible educational reforms. So the only good schools left will be private ones for rich kids. A03.6 Dilemma
3 P or Q. If P then R. If Q then S. Therefore, R or S. When R is the same as S, we have a simpler form : P or Q. If P then R. If Q then R. Therefore, R. Either we increase the tax rate or we don't. If we do, the people will be unhappy. If we don't, the people will also be unhappy. (Because the government will not have enough money to provide for public services.) So the people are going to be unhappy anyway. A03.7 Arguing by Reductio ad Absurdum The Latin name here simply means "reduced to absurdity". Here is the method of argument if you want to prove that a certain statement S is false: First assume that S is true. From the assumption that it is true, prove that it would lead to a contradiction or some other claim that is false or absurd. Conclude that S must be false. Those of you who can spot connections quickly might notice that this is none other than an application of modus tollens. A famous application of this pattern of argument is Euclid's proof that there is no largest prime number. A prime number is any positive integer greater than 1 that is wholly divisible only by 1 and by itself, e.g. 2, 3, 5, 7, 11, 13, 17, etc. Assume that there are only n prime numbers, where n is a finite number : P1 < P2 <... < Pn. Define a number Q that is 1 plus the product of all primes, i.e. Q = 1 + ( P1 x P2 x... x Pn). Q is of course larger than Pn. But Q has to be a prime number also, because (a) when it is divided by any prime number it always leave a remainder of 1, and (b) if it is not divisible by an prime number it cannot be divisible by any nonprime numbers either. So Q is a prime number larger than the largest prime number. But this is a contradiction, so the original assumption that there is a finite number of prime numbers must be wrong. So there must be infinitely many primes. Let us look at two more examples of reductio: Suppose someone were to claim that nothing is true or false. We can show that this must be false as follows : If this person's claim is indeed correct, then there is at least one thing that is true, namely the claim that the person is making. So it can't be that nothing is true or false. So his statement must be false. One theory of how the universe came about is that it developed from a vacuum state in the infinite past. Stephen Hawking thinks that this is false. Here is his argument : in order for the universe to develop from a vacuum state, the vacuum state must have been unstable. (If the vacuum state were a stable one, nothing would come out of it.) But if it was unstable, it would not be a vacuum state, and it would not have lasted an infinite time before becoming unstable. A03.8 Other Patterns
4 There are of course many other patterns of deductively valid arguments. One way to construct more patterns is to combine the ones that we have looked at earlier. For example, we can combine two cases of hypothetical syllogism to obtain the following argument: If P then Q. If Q then R. If R then S. Therefore if P then S. There are also a few other simple but also valid patterns which we have not mentioned: P and Q. Therefore Q. P. Therefore P. Some of you might be surprised to find out that "P. Therefore P." is valid. But think about it carefully  if the conclusion is also a premise, then the conclusion obviously follows from the premise! Of course, this tells us that not all valid arguments are good arguments. How these two concepts are connected is a topic we shall discuss later on. We shall look at a few more complicated patterns of valid arguments in another tutorial. It is understandable that you might not remember all the names of these patterns. But what is important is that you can recognize these argument patterns when you come across them in everyday life, and would not confuse them with patterns of invalid arguments that look similar. A03.9 Exercises Question 1 Consider the following arguments. Identify the forms of all valid arguments. Q1.1. If Jesus loves me, then I love Jesus. I do not love Jesus. Therefore, Jesus does not love me. Q1.2. Either Jimmy is walking the dog or Cathy is feeding the cat (or both). Cathy is feeding the cat. Therefore Jimmy is not walking the dog Q1.3. Either Jimmy is walking the dog or Cathy is feeding the cat. Cathy is not feeding the cat. Therefore Jimmy is walking the dog. Q1.4. If X is a man, then X is a human being. If X is a human being, then X is an animal. Therefore, if X is a man, then X is an animal. Q1.5. If I do not have Yellow Tail sashimi, then I shall have scallop sushi instead. Now, I have Yellow Tail sashimi. So I do not have scallop sushi. Q1.6. If some sheep are black, then some ducks are pink. It is not true that some ducks are pink. Therefore, it is not true that some sheep are black.
5 Q1.7. Either she is right or she is wrong. If she is right, then he is wrong. If she is wrong, then he is also wrong. Therefore, he is wrong either way. Q1.8. Paul is a bachelor. Paul is single. So at least one bachelor is single. Q1.9. Either she is in China or she is in Europe. If she is in China, then she is in Beijing. If she is in Europe, then she is sleeping. Hence, either she is in Beijing or she is sleeping. Question 2 Identify the conclusions that can be drawn from these assumptions. Which basic patterns of valid arguments should be used to derive the conclusion? If God is perfect, then God knows what people intend to do in the future. If God knows what people intend to do in the future, then God can stop people from bringing about evil. If he is dead, then there will be no pulse. If there is no pulse, then the red light will turn on. There is no red light. Either Krypto is hot or Pluto is hot. If Krypto is hot, then there is no ice on its surface. But there is. Either you speak justly or unjustly. If you speak justly then men will hate you. But if you speak unjustly the gods will hate you. Johannes is either in Hong Kong or in Thailand. He is not at home. If he is in Thailand he is staying at the Peninsula. If he is in Hong Kong he is at home. Question 3 If the following statements are all true, who killed Pam and where was Jones in 1997? Which piece of information is not needed? Jones was either in HK or in London in If Jones did not kill Pam, then Peter did. If Pam died of suffocation, then either Jones killed her, or Pam committed suicide. If Jones was in HK in 1997, then Jones did not kill Pam. Pam died of suffocation but she did not kill herself. Question 4 Suppose someone thinks that there is only a finite number of integers. How would he criticize the proof that there are infinitely many primes? Which step would he reject? Question 5 Here is a very nice example taken from the philosopher James Pryor: A computer scientist announces that he's constructed a computer program that can play the perfect game of chess: he claims that this program is guaranteed to win every game it plays, whether it plays black or white, with never a loss or a draw, and against any opponent whatsoever. The computer scientist claims to have a mathematical proof that his program will always win, but the proof runs to 500 pages of dense mathematical symbols, and no one has yet been able to verify it. Still, the program has just played 20 games against Gary Kasparov and it won every game, 10 as white and 10 as black. Should you believe the computer scientist's claim that the program is so designed that it will always win against every opponent? How would you use the reduction method to argue against the computer scientist?
6 What if two computers running the same program were to play against each other?
Selections from Aristotle s Prior Analytics 41a21 41b5
Lesson Seventeen The Conditional Syllogism Selections from Aristotle s Prior Analytics 41a21 41b5 It is clear then that the ostensive syllogisms are effected by means of the aforesaid figures; these considerations
More informationPHILOSOPHY 102 INTRODUCTION TO LOGIC PRACTICE EXAM 1. W# Section (10 or 11) 4. T F The statements that compose a disjunction are called conjuncts.
PHILOSOPHY 102 INTRODUCTION TO LOGIC PRACTICE EXAM 1 W# Section (10 or 11) 1. True or False (5 points) Directions: Circle the letter next to the best answer. 1. T F All true statements are valid. 2. T
More informationChapter 8  Sentential Truth Tables and Argument Forms
Logic: A Brief Introduction Ronald L. Hall Stetson University Chapter 8  Sentential ruth ables and Argument orms 8.1 Introduction he truthvalue of a given truthfunctional compound proposition depends
More informationRelevance. Premises are relevant to the conclusion when the truth of the premises provide some evidence that the conclusion is true
Relevance Premises are relevant to the conclusion when the truth of the premises provide some evidence that the conclusion is true Premises are irrelevant when they do not 1 Non Sequitur Latin for it does
More informationHOW TO ANALYZE AN ARGUMENT
What does it mean to provide an argument for a statement? To provide an argument for a statement is an activity we carry out both in our everyday lives and within the sciences. We provide arguments for
More informationPhilosophical Arguments
Philosophical Arguments An introduction to logic and philosophical reasoning. Nathan D. Smith, PhD. Houston Community College Nathan D. Smith. Some rights reserved You are free to copy this book, to distribute
More informationSession 10 INDUCTIVE REASONONING IN THE SCIENCES & EVERYDAY LIFE( PART 1)
UGRC 150 CRITICAL THINKING & PRACTICAL REASONING Session 10 INDUCTIVE REASONONING IN THE SCIENCES & EVERYDAY LIFE( PART 1) Lecturer: Dr. Mohammed Majeed, Dept. of Philosophy & Classics, UG Contact Information:
More informationHANDBOOK (New or substantially modified material appears in boxes.)
1 HANDBOOK (New or substantially modified material appears in boxes.) I. ARGUMENT RECOGNITION Important Concepts An argument is a unit of reasoning that attempts to prove that a certain idea is true by
More informationChapter 1. Introduction. 1.1 Deductive and Plausible Reasoning Strong Syllogism
Contents 1 Introduction 3 1.1 Deductive and Plausible Reasoning................... 3 1.1.1 Strong Syllogism......................... 3 1.1.2 Weak Syllogism.......................... 4 1.1.3 Transitivity
More informationMCQ IN TRADITIONAL LOGIC. 1. Logic is the science of A) Thought. B) Beauty. C) Mind. D) Goodness
MCQ IN TRADITIONAL LOGIC FOR PRIVATE REGISTRATION TO BA PHILOSOPHY PROGRAMME 1. Logic is the science of. A) Thought B) Beauty C) Mind D) Goodness 2. Aesthetics is the science of .
More informationUnit. Categorical Syllogism. What is a syllogism? Types of Syllogism
Unit 8 Categorical yllogism What is a syllogism? Inference or reasoning is the process of passing from one or more propositions to another with some justification. This inference when expressed in language
More informationWhat is an argument? PHIL 110. Is this an argument? Is this an argument? What about this? And what about this?
What is an argument? PHIL 110 Lecture on Chapter 3 of How to think about weird things An argument is a collection of two or more claims, one of which is the conclusion and the rest of which are the premises.
More informationChapter 9 Sentential Proofs
Logic: A Brief Introduction Ronald L. Hall, Stetson University Chapter 9 Sentential roofs 9.1 Introduction So far we have introduced three ways of assessing the validity of truthfunctional arguments.
More informationLogic: A Brief Introduction
Logic: A Brief Introduction Ronald L. Hall, Stetson University PART III  Symbolic Logic Chapter 7  Sentential Propositions 7.1 Introduction What has been made abundantly clear in the previous discussion
More informationA short introduction to formal logic
A short introduction to formal logic Dan Hicks v0.3.2, July 20, 2012 Thanks to Tim Pawl and my Fall 2011 Intro to Philosophy students for feedback on earlier versions. My approach to teaching logic has
More information4.1 A problem with semantic demonstrations of validity
4. Proofs 4.1 A problem with semantic demonstrations of validity Given that we can test an argument for validity, it might seem that we have a fully developed system to study arguments. However, there
More informationIn view of the fact that IN CLASS LOGIC EXERCISES
IN CLASS LOGIC EXERCISES Instructions: Determine whether the following are propositions. If some are not propositions, see if they can be rewritten as propositions. (1) I have a very refined sense of smell.
More informationHandout 1: Arguments  the basics because, since, given that, for because Given that Since for Because
Handout 1: Arguments  the basics It is useful to think of an argument as a list of sentences.[1] The last sentence is the conclusion, and the other sentences are the premises. Thus: (1) No professors
More informationb) The meaning of "child" would need to be taken in the sense of age, as most people would find the idea of a young child going to jail as wrong.
Explanation for Question 1 in Quiz 8 by Norva Lo  Tuesday, 18 September 2012, 9:39 AM The following is the solution for Question 1 in Quiz 8: (a) Which term in the argument is being equivocated. (b) What
More informationPhil 3304 Introduction to Logic Dr. David Naugle. Identifying Arguments i
Phil 3304 Introduction to Logic Dr. David Naugle Identifying Arguments Dallas Baptist University Introduction Identifying Arguments i Any kid who has played with tinker toys and Lincoln logs knows that
More informationPractice Test Three Spring True or False True = A, False = B
Practice Test Three Spring 2015 True or False True = A, False = B 1. A sound argument is a valid deductive argument with true premisses. 2. A conclusion is a statement of support. 3. An easy way to determine
More informationIntroduction to Logic
University of Notre Dame Fall, 2015 Arguments Philosophy is difficult. If questions are easy to decide, they usually don t end up in philosophy The easiest way to proceed on difficult questions is to formulate
More informationPHIL 115: Philosophical Anthropology. I. Propositional Forms (in Stoic Logic) Lecture #4: Stoic Logic
HIL 115: hilosophical Anthropology Lecture #4: Stoic Logic Arguments from the Euthyphro: Meletus Argument (according to Socrates) [3ab] Argument: Socrates is a maker of gods; so, Socrates corrupts the
More informationINTERMEDIATE LOGIC Glossary of key terms
1 GLOSSARY INTERMEDIATE LOGIC BY JAMES B. NANCE INTERMEDIATE LOGIC Glossary of key terms This glossary includes terms that are defined in the text in the lesson and on the page noted. It does not include
More informationAnnouncements. CS311H: Discrete Mathematics. First Order Logic, Rules of Inference. Satisfiability, Validity in FOL. Example.
Announcements CS311H: Discrete Mathematics First Order Logic, Rules of Inference Instructor: Işıl Dillig Homework 1 is due now! Homework 2 is handed out today Homework 2 is due next Wednesday Instructor:
More informationBasic Concepts and Skills!
Basic Concepts and Skills! Critical Thinking tests rationales,! i.e., reasons connected to conclusions by justifying or explaining principles! Why do CT?! Answer: Opinions without logical or evidential
More information1. To arrive at the truth we have to reason correctly. 2. Logic is the study of correct reasoning. B. DEDUCTIVE AND INDUCTIVE ARGUMENTS
I. LOGIC AND ARGUMENTATION 1 A. LOGIC 1. To arrive at the truth we have to reason correctly. 2. Logic is the study of correct reasoning. 3. It doesn t attempt to determine how people in fact reason. 4.
More informationSection 3.5. Symbolic Arguments. Copyright 2013, 2010, 2007, Pearson, Education, Inc.
Section 3.5 Symbolic Arguments What You Will Learn Symbolic arguments Standard forms of arguments 3.52 Symbolic Arguments A symbolic argument consists of a set of premises and a conclusion. It is called
More informationThe Philosopher s World Cup
The Philosopher s World Cup Monty Python & the Flying Circus http://www.youtube.com/watch?v=92vv3qgagck&feature=related What is an argument? http://www.youtube.com/watch?v=kqfkti6gn9y What is an argument?
More informationUnit 4. Reason as a way of knowing. Tuesday, March 4, 14
Unit 4 Reason as a way of knowing I. Reasoning At its core, reasoning is using what is known as building blocks to create new knowledge I use the words logic and reasoning interchangeably. Technically,
More informationArgument and Persuasion. Stating Opinions and Proposals
Argument and Persuasion Stating Opinions and Proposals The Method It all starts with an opinion  something that people can agree or disagree with. The Method Move to action Speak your mind Convince someone
More informationWhat is the Nature of Logic? Judy Pelham Philosophy, York University, Canada July 16, 2013 PanHellenic Logic Symposium Athens, Greece
What is the Nature of Logic? Judy Pelham Philosophy, York University, Canada July 16, 2013 PanHellenic Logic Symposium Athens, Greece Outline of this Talk 1. What is the nature of logic? Some history
More informationPHILOSOPHER S TOOL KIT 1. ARGUMENTS PROFESSOR JULIE YOO 1.1 DEDUCTIVE VS INDUCTIVE ARGUMENTS
PHILOSOPHER S TOOL KIT PROFESSOR JULIE YOO 1. Arguments 1.1 Deductive vs Induction Arguments 1.2 Common Deductive Argument Forms 1.3 Common Inductive Argument Forms 1.4 Deduction: Validity and Soundness
More informationVideo: How does understanding whether or not an argument is inductive or deductive help me?
Page 1 of 10 10b Learn how to evaluate verbal and visual arguments. Video: How does understanding whether or not an argument is inductive or deductive help me? Download transcript Three common ways to
More informationLecture 17:Inference Michael Fourman
Lecture 17:Inference Michael Fourman 2 Is this a valid argument? Assumptions: If the races are fixed or the gambling houses are crooked, then the tourist trade will decline. If the tourist trade declines
More informationLogic, reasoning and fallacies. Example 0: valid reasoning. Decide how to make a random choice. Valid reasoning. Random choice of X, Y, Z, n
Logic, reasoning and fallacies and some puzzling Before we start Introductory Examples Karst Koymans Informatics Institute University of Amsterdam (version 16.3, 2016/11/21 12:58:26) Wednesday, November
More information9 Methods of Deduction
M09_COPI1396_13_SE_C09.QXD 10/19/07 3:46 AM Page 372 9 Methods of Deduction 9.1 Formal Proof of Validity 9.2 The Elementary Valid Argument Forms 9.3 Formal Proofs of Validity Exhibited 9.4 Constructing
More information5.6.1 Formal validity in categorical deductive arguments
Deductive arguments are commonly used in various kinds of academic writing. In order to be able to perform a critique of deductive arguments, we will need to understand their basic structure. As will be
More informationCRITICAL THINKING. Formal v Informal Fallacies
CRITICAL THINKING FAULTY REASONING (VAUGHN CH. 5) LECTURE PROFESSOR JULIE YOO Formal v Informal Fallacies Irrelevant Premises Genetic Fallacy Composition Division Appeal to the Person (ad hominem/tu quoque)
More informationGenuine dichotomies expressed using either/or statements are always true:
CRITICAL THINKING HANDOUT 13 DILEMMAS You re either part of the solution or you re part of the problem Attributed to Eldridge Cleaver, 1968 Over time it s going to be important for nations to know they
More informationArgument Forms. 1.2 Forms and Validity
1.2 Forms and Validity Deductive logic is the study of methods for determining whether or not an argument is valid. This section introduces the concept of an argument form and explains how an understanding
More information1.5. Argument Forms: Proving Invalidity
18. If inflation heats up, then interest rates will rise. If interest rates rise, then bond prices will decline. Therefore, if inflation heats up, then bond prices will decline. 19. Statistics reveal that
More informationDoes God exist? The argument from evil
Does God exist? The argument from evil There are two especially important arguments against belief in God. The first is based on the (alleged) lack of evidence for God s existence, and the rule that one
More informationChapter 5: Ways of knowing Reason (p. 111)
Chapter 5: Ways of knowing Reason (p. 111) Neils Bohr (1885 1962) to Einstein: You are not thinking. You are merely being logical. Reason is one of the four ways of knowing: Perception Language Emotion
More informationThe Little Logic Book Hardy, Ratzsch, Konyndyk De Young and Mellema The Calvin College Press, 2013
The Little Logic Book Hardy, Ratzsch, Konyndyk De Young and Mellema The Calvin College Press, 2013 Exercises for The Little Logic Book may be downloaded by the instructor as Word documents and then modified
More informationExposition of Symbolic Logic with KalishMontague derivations
An Exposition of Symbolic Logic with KalishMontague derivations Copyright 200613 by Terence Parsons all rights reserved Aug 2013 Preface The system of logic used here is essentially that of Kalish &
More informationThe Problem of Induction and Popper s Deductivism
The Problem of Induction and Popper s Deductivism Issues: I. Problem of Induction II. Popper s rejection of induction III. Salmon s critique of deductivism 2 I. The problem of induction 1. Inductive vs.
More informationReplies to Hasker and Zimmerman. Trenton Merricks. Molinism: The Contemporary Debate edited by Ken Perszyk. Oxford University Press, I.
Replies to Hasker and Zimmerman Trenton Merricks Molinism: The Contemporary Debate edited by Ken Perszyk. Oxford University Press, 2011. I. Hasker Here is how arguments by reductio work: you show that
More information1.6 Validity and Truth
M01_COPI1396_13_SE_C01.QXD 10/10/07 9:48 PM Page 30 30 CHAPTER 1 Basic Logical Concepts deductive arguments about probabilities themselves, in which the probability of a certain combination of events is
More informationI. What is an Argument?
I. What is an Argument? In philosophy, an argument is not a dispute or debate, but rather a structured defense of a claim (statement, assertion) about some topic. When making an argument, one does not
More informationCosmological arguments for the Existence of God Gerald Jones Dialogue Issue 26 April 2006
Cosmological arguments for the Existence of God Gerald Jones Dialogue Issue 26 April 2006 In its most basic form, a cosmological argument attempts to understand and answer the question 'Why is there a
More informationMITOCW Lec 2 MIT 6.042J Mathematics for Computer Science, Fall 2010
MITOCW Lec 2 MIT 6.042J Mathematics for Computer Science, Fall 2010 The following content is provided under a Creative Commons license. Your support will help MIT OpenCourseWare continue to offer high
More informationReductio ad Absurdum, Modulation, and Logical Forms. Miguel LópezAstorga 1
International Journal of Philosophy and Theology June 25, Vol. 3, No., pp. 5965 ISSN: 2333575 (Print), 23335769 (Online) Copyright The Author(s). All Rights Reserved. Published by American Research
More informationDoes God exist? The argument from evil
Does God exist? The argument from evil One of the oldest, and most important, arguments against the existence of God tries to show that the idea that God is allpowerful and allgood contradicts a very
More informationPractice Test Three Fall True or False True = A, False = B
Practice Test Three Fall 2015 True or False True = A, False = B 1. The inclusive "or" means "A or B or both A and B." 2. The conclusion contains both the major term and the middle term. 3. "If, then" statements
More informationLogic: Deductive and Inductive by Carveth Read M.A. CHAPTER IX CHAPTER IX FORMAL CONDITIONS OF MEDIATE INFERENCE
CHAPTER IX CHAPTER IX FORMAL CONDITIONS OF MEDIATE INFERENCE Section 1. A Mediate Inference is a proposition that depends for proof upon two or more other propositions, so connected together by one or
More informationLay75879_ch01 11/17/03 2:03 PM Page x
Lay75879_ch01 11/17/03 2:03 PM Page x McGrawHill Higher Education Layman: The Power of Logic, 3e CHAPTER 1 / Page x Lay75879_ch01 11/17/03 2:03 PM Page 1 McGrawHill Higher Education Layman: The Power
More informationLawrence Brian Lombard a a Wayne State University. To link to this article:
This article was downloaded by: [Wayne State University] On: 29 August 2011, At: 05:20 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer
More informationLogic and Argument Analysis: An Introduction to Formal Logic and Philosophic Method (REVISED)
Carnegie Mellon University Research Showcase @ CMU Department of Philosophy Dietrich College of Humanities and Social Sciences 1985 Logic and Argument Analysis: An Introduction to Formal Logic and Philosophic
More informationSuppressed premises in real life. Philosophy and Logic Section 4.3 & Some Exercises
Suppressed premises in real life Philosophy and Logic Section 4.3 & Some Exercises Analyzing inferences: finale Suppressed premises: from mechanical solutions to elegant ones Practicing on some reallife
More informationDescartes and Foundationalism
Cogito, ergo sum Who was René Descartes? 15961650 Life and Times Notable accomplishments modern philosophy mind body problem epistemology physics inertia optics mathematics functions analytic geometry
More informationTruth and Molinism * Trenton Merricks. Molinism: The Contemporary Debate edited by Ken Perszyk. Oxford University Press, 2011.
Truth and Molinism * Trenton Merricks Molinism: The Contemporary Debate edited by Ken Perszyk. Oxford University Press, 2011. According to Luis de Molina, God knows what each and every possible human would
More informationEthical Consistency and the Logic of Ought
Ethical Consistency and the Logic of Ought Mathieu Beirlaen Ghent University In Ethical Consistency, Bernard Williams vindicated the possibility of moral conflicts; he proposed to consistently allow for
More informationA Judgmental Formulation of Modal Logic
A Judgmental Formulation of Modal Logic Sungwoo Park Pohang University of Science and Technology South Korea Estonian Theory Days Jan 30, 2009 Outline Study of logic Model theory vs Proof theory Classical
More informationA Critique of Friedman s Critics Lawrence A. Boland
Revised final draft A Critique of Friedman s Critics Milton Friedman s essay The methodology of positive economics [1953] is considered authoritative by almost every textbook writer who wishes to discuss
More informationA Brief Introduction to Key Terms
1 A Brief Introduction to Key Terms 5 A Brief Introduction to Key Terms 1.1 Arguments Arguments crop up in conversations, political debates, lectures, editorials, comic strips, novels, television programs,
More informationWhat we want to know is: why might one adopt this fatalistic attitude in response to reflection on the existence of truths about the future?
Fate and free will From the first person point of view, one of the most obvious, and important, facts about the world is that some things are up to us at least sometimes, we are able to do one thing, and
More informationRelativism and the Nature of Truth
Relativism and the Nature of Truth by Roger L. Smalling, D.Min Truth exists Any other premise is selfinvalidating. Take, for instance, the thought: Truth does not exist. Is that statement a truth? If
More informationA. Problem set #3 it has been posted and is due Tuesday, 15 November
Lecture 9: Propositional Logic I Philosophy 130 1 & 3 November 2016 O Rourke & Gibson I. Administrative A. Problem set #3 it has been posted and is due Tuesday, 15 November B. I am working on the group
More informationFaith indeed tells what the senses do not tell, but not the contrary of what they see. It is above them and not contrary to them.
19 Chapter 3 19 CHAPTER 3: Logic Faith indeed tells what the senses do not tell, but not the contrary of what they see. It is above them and not contrary to them. The last proceeding of reason is to recognize
More informationThe Problem of Major Premise in Buddhist Logic
The Problem of Major Premise in Buddhist Logic TANG Mingjun The Institute of Philosophy Shanghai Academy of Social Sciences Shanghai, P.R. China Abstract: This paper is a preliminary inquiry into the main
More informationIntroduction to Philosophy. Spring 2017
Introduction to Philosophy Spring 2017 Elements of The Matrix The Matrix obviously has a lot of interesting parallels, themes, philosophical points, etc. For this class, the most interesting are the religious
More informationChapter 3: Basic Propositional Logic. Based on Harry Gensler s book For CS2209A/B By Dr. Charles Ling;
Chapter 3: Basic Propositional Logic Based on Harry Gensler s book For CS2209A/B By Dr. Charles Ling; cling@csd.uwo.ca The Ultimate Goals Accepting premises (as true), is the conclusion (always) true?
More informationDoes the Third Man Argument refute the theory of forms?
Does the Third Man Argument refute the theory of forms? Fine [1993] recognises four versions of the Third Man Argument (TMA). However, she argues persuasively that these are similar arguments with similar
More informationThirty  Eight Ways to Win an Argument from Schopenhauer's "The Art of Controversy"...per fas et nefas :)
Page 1 of 5 Thirty  Eight Ways to Win an Argument from Schopenhauer's "The Art of Controversy"...per fas et nefas :) (Courtesy of searchlore ~ Back to the trolls lore ~ original german text) 1 Carry
More informationLOGICAL FALLACIES/ERRORS OF ARGUMENT
LOGICAL FALLACIES/ERRORS OF ARGUMENT Deduction Fallacies Term Definition Example(s) 1 Equivocation Ambiguity 2 types: The word or phrase may be ambiguous, in which case it has more than one distinct meaning
More informationLemon Bay High School AP Language and Composition ENC 1102 Mr. Hertz
Lemon Bay High School AP Language and Composition ENC 1102 Mr. Hertz Please take out a few pieces of paper and a pen or pencil. Write your name, the date, your class period, and a title at the top of the
More informationAlice E. Fischer. CSCI 1166 Discrete Mathematics for Computing February, 2018
Alice E. Fischer CSCI 1166 Discrete Mathematics for Computing February, 2018 Alice E. Fischer... 1/28 1 Examples and Varieties Order of Quantifiers and Negations 2 3 Universal Existential 4 Universal Modus
More informationA GNOSTIC CHRISTIANITY
Oct. 9, 2014; 4 pm. Seminar at the Department for the Study of Religions, University of Szeged, Petőfi Sándor avenue 3034, Petőfi building, first floor, room II. A GNOSTIC CHRISTIANITY Some developing
More informationThree Kinds of Arguments
Chapter 27 Three Kinds of Arguments Arguments in general We ve been focusing on Moleculananalyzable arguments for several chapters, but now we want to take a step back and look at the big picture, at
More informationDescartes Method of Doubt
Descartes Method of Doubt Philosophy 100 Lecture 9 PUTTING IT TOGETHER. Descartes Idea 1. The New Science. What science is about is describing the nature and interaction of the ultimate constituents of
More informationStatistical Syllogistic, Part 1
University of Windsor Scholarship at UWindsor OSSA Conference Archive OSSA 4 May 17th, 9:00 AM  May 19th, 5:00 PM Statistical Syllogistic, Part 1 Lawrence H. Powers Follow this and additional works at:
More informationLogical (formal) fallacies
Fallacies in academic writing Chad Nilep There are many possible sources of fallacy an idea that is mistakenly thought to be true, even though it may be untrue in academic writing. The phrase logical fallacy
More informationCosmological Argument
Theistic Arguments: The Craig Program, 2 Edwin Chong February 27, 2005 Cosmological Argument God makes sense of the origin of the universe. Kalam cosmological argument. [Craig 1979] Kalam: An Arabic term
More informationI Don't Believe in God I Believe in Science
I Don't Believe in God I Believe in Science This seems to be a common world view that many people hold today. It is important that when we look at statements like this we spend a proper amount of time
More information6: DEDUCTIVE LOGIC. Chapter 17: Deductive validity and invalidity Ben Bayer Drafted April 25, 2010 Revised August 23, 2010
6: DEDUCTIVE LOGIC Chapter 17: Deductive validity and invalidity Ben Bayer Drafted April 25, 2010 Revised August 23, 2010 Deduction vs. induction reviewed In chapter 14, we spent a fair amount of time
More informationDenying the Antecedent as a Legitimate Argumentative Strategy: A Dialectical Model
Denying the Antecedent as a Legitimate Argumentative Strategy 219 Denying the Antecedent as a Legitimate Argumentative Strategy: A Dialectical Model DAVID M. GODDEN DOUGLAS WALTON University of Windsor
More information10 CERTAINTY G.E. MOORE: SELECTED WRITINGS
10 170 I am at present, as you can all see, in a room and not in the open air; I am standing up, and not either sitting or lying down; I have clothes on, and am not absolutely naked; I am speaking in a
More informationAn alternative understanding of interpretations: Incompatibility Semantics
An alternative understanding of interpretations: Incompatibility Semantics 1. In traditional (truththeoretic) semantics, interpretations serve to specify when statements are true and when they are false.
More informationA BRIEF INTRODUCTION TO LOGIC FOR METAPHYSICIANS
A BRIEF INTRODUCTION TO LOGIC FOR METAPHYSICIANS 0. Logic, Probability, and Formal Structure Logic is often divided into two distinct areas, inductive logic and deductive logic. Inductive logic is concerned
More informationThe problems of induction in scientific inquiry: Challenges and solutions. Table of Contents 1.0 Introduction Defining induction...
The problems of induction in scientific inquiry: Challenges and solutions Table of Contents 1.0 Introduction... 2 2.0 Defining induction... 2 3.0 Induction versus deduction... 2 4.0 Hume's descriptive
More informationIntroductory Matters
1 Introductory Matters The readings in this section take up some topics that set the stage for discussion to follow. The first addresses the value of philosophy, the second the nature of truth, and the
More informationWorksheet Exercise 1.1. Logic Questions
Worksheet Exercise 1.1. Logic Questions Date Study questions. These questions do not have easy answers. (But that doesn't mean that they have no answers.) Just think about these issues. There is no particular
More informationSymbolic Logic. 8.1 Modern Logic and Its Symbolic Language
M08_COPI1396_13_SE_C08.QXD 10/16/07 9:19 PM Page 315 Symbolic Logic 8 8.1 Modern Logic and Its Symbolic Language 8.2 The Symbols for Conjunction, Negation, and Disjunction 8.3 Conditional Statements and
More informationSpinoza, Ethics 1 of 85 THE ETHICS. by Benedict de Spinoza (Ethica Ordine Geometrico Demonstrata) Translated from the Latin by R. H. M.
Spinoza, Ethics 1 of 85 THE ETHICS by Benedict de Spinoza (Ethica Ordine Geometrico Demonstrata) Translated from the Latin by R. H. M. Elwes PART I: CONCERNING GOD DEFINITIONS (1) By that which is selfcaused
More informationMoral Argument. Theistic Arguments: The Craig Program, 4. Edwin Chong. God makes sense of the objective moral values in the world.
Theistic Arguments: The Craig Program, 4 Edwin Chong March 13, 2005 Moral Argument God makes sense of the objective moral values in the world. March 2005 2 1 The Argument If God does not exist, objective
More informationBoghossian & Harman on the analytic theory of the a priori
Boghossian & Harman on the analytic theory of the a priori PHIL 83104 November 2, 2011 Both Boghossian and Harman address themselves to the question of whether our a priori knowledge can be explained in
More informationExercise Sets. KS Philosophical Logic: Modality, Conditionals Vagueness. Dirk Kindermann University of Graz July 2014
Exercise Sets KS Philosophical Logic: Modality, Conditionals Vagueness Dirk Kindermann University of Graz July 2014 1 Exercise Set 1 Propositional and Predicate Logic 1. Use Definition 1.1 (Handout I Propositional
More informationChristCentered Critical Thinking. Lesson 7: Logical Fallacies
ChristCentered Critical Thinking Lesson 7: Logical Fallacies 1 Learning Outcomes In this lesson we will: 1.Define logical fallacy using the SEEI. 2.Understand and apply the concept of relevance. 3.Define,
More informationAlan Shlemon. Stand to Reason
Tactics in the Defending Faith Alan Shlemon Stand to Reason www.str.org Ambassadors for Christ 2 Corinthians 5:20 Knowledge: an accurately formed mind Wisdom: an artful method Character: an attractive
More information