# Conditionals IV: Is Modus Ponens Valid?

Save this PDF as:

Size: px
Start display at page:

## Transcription

1 Conditionals IV: Is Modus Ponens Valid? UC Berkeley, Philosophy 142, Spring 2016 John MacFarlane 1 The intuitive counterexamples McGee [2] offers these intuitive counterexamples to Modus Ponens: 1. (a) If a Republican will win the election, then if Reagan will not win, Anderson will win. (b) A Republican will win the election. (c) So, if Reagan will not win, Anderson will win. 2. (a) If that creature is a fish, then if it has lungs, it is a lungfish. (b) That creature is a fish. (c) So, if it has lungs, it is a lungfish. 3. (a) If Uncle Otto doesn t find gold, then if he strikes it rich, he will strike it rich by finding silver. (b) Uncle Otto won t find gold. (c) So, if Uncle Otto strikes it rich, he will strike it rich by finding silver. 2 Some important distinctions We have seen from Stalnaker the importance of distinguishing between two questions: 1. If the premises are true at a world, does the conclusion have to be true at that world? 2. If the premises are accepted (true throughout the context set), does the conclusion have to be accepted? Showing (2) doesn t establish (1). We have already seen several examples of inferences that are acceptance-preserving but not truth-preserving. For example, B, therefore if A, then B. Has McGee given us counterexamples to the claim that Modus Ponens is acceptancepreserving? It seems not. Surely, if it is believed with certainty (or accepted or presupposed) that a Republican will win, we must conclude that if Reagan does not win, Anderson will. But, even if MP is acceptance-preserving, it might not be truth-preserving. Suppose that we have good but not conclusive grounds for accepting the premises; that is, grounds for assigning a high probability. Might we still have conclusive grounds for rejecting the conclusion? We can map our credences as follows (bigger area = larger probability): April 14,

2 2. Some important distinctions Carter Reagan Anderson 1. If a Republican will win the election, then if Reagan will not win, Anderson will win. 2. A Republican will win the election. 3. So, if Reagan will not win, Anderson will win. Not a fish Lungs Fish 1. If that creature is a fish, then if it has lungs, it is a lungfish. 2. That creature is a fish. 3. So, if it has lungs, it is a lungfish. Otto finds gold Otto gets rich Otto finds silver 1. If Uncle Otto doesn t find gold, then if he strikes it rich, he will strike it rich by finding silver. 2. Uncle Otto won t find gold. 3. So, if Uncle Otto strikes it rich, he will strike it rich by finding silver. If we apply Edgington s test for the acceptability of an indicative conditional, this will give us cases where the premises are acceptable to a high degree, but the conclusion is not. This answers the question: 3. If we assign high credence to the premises, must we assign high credence to the conclusion? But note that a No answer to (3) doesn t imply a No answer to (1). Compare (for a 6-sided die): The die will not land 1. The die will not land 2. The die will not land 3. The die will not land 4. The die will not land 5. So, the die will land 6. Here we can have a high credence to each premise but a low credence in their conjunction, and hence a low credence in their conclusion. We might ask instead: April 14,

3 3. Direct assessments 4. If we assign high credence to the conjunction of the premises, must we assign high credence to the conclusion? In McGee s cases, do we assign a high credence to the conjunction of the premises? Well, here there are only two premises. Assume that A and A B are probabilistically independent. Then the probability of their conjunction is the product of their probabilities. If we have 0.9 credence in both, then, our credence in their conjunction should be 0.81, which is still fairly high. Note also that the (a) premise in each of McGee s examples seems to be something we might believe with credence 1. 3 Direct assessments Instead of asking about whether it would be okay to infer the conclusions from the premises in McGee s examples, we might try assessing the truth values of the premises and conclusions in different scenarios. It is important to keep in mind here that, on most semantics for the indicative conditional, it will be highly contextually sensitive. For example, on Stalnaker s view, the truth of if A then B can depend on (a) what respects of similarity are contextually relevant and (b) on what has been presupposed (what the context set is). For example, as we have seen, if B is presupposed and A is compatible with what is presupposed, then A B is guaranteed to be true. (The closest A-world will have to be in the context set, and so it will be a B world.) But if B is not presupposed, A B can be false, even if B is true. Now let s suppose that, shortly before the 1980 election, Sarah uttered (1a) and (1b). Suppose that the context set governing her conversation at this time includes worlds where Reagan, worlds where Carter, and worlds where Anderson. As far as she is presupposing, any of the candidates could win. Did she speak truly in uttering (1a)? Plausibly, yes. She knew that Anderson and Reagan were the only Republican candidates. Did she speak truly in uttering (1b)? We know that she did, since Reagan, a Republican, did win the election. Did she speak truly in uttering (1c)? That is harder to answer, since the truth conditions of indicative conditionals are disputed. But let s think about it from the standpoint of Stalnaker s view. What was the closest world to the actual world where Reagan did not win? Presumably it was a world where Carter won, not a world where Anderson did. So (1c) was false, in Sarah s context. Granted, if it had been accepted in Sarah s context that a Republican would win, then (1c) would have been true in her context, because there would be no worlds in the context set where Carter. But let s imagine a case where this is not accepted. (Imagine either that Sarah is not making an assertion in uttering (1b), or that she is making an assertion, but her conversational partners don t accept it.) April 14,

4 4. Modus ponens vs exportation But hold on! We know that on Stalnaker s semantics, modus ponens is valid. If A and A B are both true at a world, B has to be true at that world. And now we re saying that Stalnaker s semantics agrees with McGee that (1c) is false, in the imagined context. So what s going on? Stalnaker will have to deny that either (1b) or (1a) expresses a truth. (1b) is undeniably true, so he will have to reject (1a). If we think about Stalnaker s semantics, it s easy to see that it doesn t vindicate our intuition that Sarah s utterance of (1a) is true. Consider the actual world. It s a world where a Republican will win the election. So (1a) is true at that world if (1c) is true at that world. We have just seen that (1c) is not true at that world, since the closest world where Reagan does not win is a world where Carter. So (1a) is not true either. McGee would say: This doesn t show that we don t have a counterexample to modus ponens. It just shows that Stalnaker s semantics is not right. For clearly (1a) is true in the imagined context. 4 Modus ponens vs exportation McGee argues that if we want a counditional that is stronger than the material conditional and weaker than strict implication, we need to choose between modus ponens and Exportation (A B) C A (B C ) He gives the argument with a great deal of rigor [2, pp ]. The basic idea, though, is very simple (it is similar to an idea from Allan Gibbard s [1]): 1. Suppose A B. 2. (A B) A logically implies B. (fact) 3. So, ((A B) A) B. (StrImp: If φ logically implies ψ, then φ ψ is true) 4. So, (A B) (A B). (Exportation) 5. So, A B. (Modus ponens for from 1 and 4) So, if we have exportation and StrImp, the material conditional implies the indicative! We can fix this by: (a) giving up the assumption that is weaker than strict implication and stronger than. (b) giving up exportation. (c) giving up modus ponens. McGee argues that we should choose (c). Exportation is plausible across the board, he thinks arguing inductively from some examples! Can you think of counterexamples? McGee notes that Stalnaker s semantics does not seem to endores exportation. What would Stalnaker s semantics say about the following two conditionals? April 14,

5 REFERENCES REFERENCES (1) If Reagan hadn t won the election and a Republican had won, it would have been Anderson. (2) If Reagan hadn t won the election, then if a Republican had won, it would have been Anderson. References [1] Allan Gibbard. Two Recent Theories of Conditionals. In: IFS: Conditionals, Belief, Decision, Chance, and Time. Ed. by William L. Harper, Robert Stalnaker, and Glenn Pearce. 1981, pp [2] Vann McGee. A Counterexample to Modus Ponens. In: Journal of Philosophy 82 (1985), pp April 14,

### Exercise 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

### The 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.

### Modus Ponens Defended

Modus Ponens Defended Justin Bledin June 26, 2014 Abstract: Is modus ponens for the indicative conditional valid? McGee [1985] famously presents several alleged counterexamples to this rule of inference.

### Ten miners are trapped either in shaft A or in shaft B, but we

c. c THE JOURNAL OF PHILOSOPHY volume cvii, no. 3, march 2010 c. c IFS AND OUGHTS * Ten miners are trapped either in shaft A or in shaft B, but we do not know which. Flood waters threaten to flood the

### Chapter 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

### TWO VERSIONS OF HUME S LAW

DISCUSSION NOTE BY CAMPBELL BROWN JOURNAL OF ETHICS & SOCIAL PHILOSOPHY DISCUSSION NOTE MAY 2015 URL: WWW.JESP.ORG COPYRIGHT CAMPBELL BROWN 2015 Two Versions of Hume s Law MORAL CONCLUSIONS CANNOT VALIDLY

### Justified Inference. Ralph Wedgwood

Justified Inference Ralph Wedgwood In this essay, I shall propose a general conception of the kind of inference that counts as justified or rational. This conception involves a version of the idea that

### Practical Conditionals

Practical Conditionals Jamie Dreier This is a very drafty draft, so please don t cite it. Introduction Sometimes we are under conditional requirements to do things. We can express them like this: If p,

### Modal disagreements. Justin Khoo. Forthcoming in Inquiry

Modal disagreements Justin Khoo jkhoo@mit.edu Forthcoming in Inquiry Abstract It s often assumed that when one party felicitously rejects an assertion made by another party, the first party thinks that

### Factual detachment and speaker endorsement

Factual detachment and speaker endorsement Cleo Condoravdi Stanford University Joint work with Sven Lauer, Zukunftskolleg, University of Konstanz Logic Colloquium University of Connecticut May 1, 2015

### G.E. Moore A Refutation of Skepticism

G.E. Moore A Refutation of Skepticism The Argument For Skepticism 1. If you do not know that you are not merely a brain in a vat, then you do not even know that you have hands. 2. You do not know that

### Philosophical 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

### 1. My thesis: the conditionals of deliberation are indicatives

12.0, 34.8, 42.9 The Conditionals of Deliberation KEITH DEROSE Practical deliberation often involves conditional judgements about what will (likely) happen if certain alternatives are pursued. It is widely

### Conditionals, Predicates and Probability

Conditionals, Predicates and Probability Abstract Ernest Adams has claimed that a probabilistic account of validity gives the best account of our intuitive judgements about the validity of arguments. In

### An alternative understanding of interpretations: Incompatibility Semantics

An alternative understanding of interpretations: Incompatibility Semantics 1. In traditional (truth-theoretic) semantics, interpretations serve to specify when statements are true and when they are false.

### The Logic of Confusion. Remarks on Joseph Camp s Confusion: A Study in the Theory of Knowledge. John MacFarlane (University of California, Berkeley)

The Logic of Confusion Remarks on Joseph Camp s Confusion: A Study in the Theory of Knowledge John MacFarlane (University of California, Berkeley) Because I am color blind, I routinely wear mismatched

### HANDBOOK (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

### Intuition as Philosophical Evidence

Essays in Philosophy Volume 13 Issue 1 Philosophical Methodology Article 17 January 2012 Intuition as Philosophical Evidence Federico Mathías Pailos University of Buenos Aires Follow this and additional

### Is Logic a Normative Discipline?

Is Logic a Normative Discipline? John MacFarlane June 14, 2017 Conference on the Normativity of Logic University of Bergen Please do not cite or circulate without permission I Is logic a normative discipline?

### 4.1 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

### Instrumental Normativity: In Defense of the Transmission Principle Benjamin Kiesewetter

Instrumental Normativity: In Defense of the Transmission Principle Benjamin Kiesewetter This is the penultimate draft of an article forthcoming in: Ethics (July 2015) Abstract: If you ought to perform

### RALPH WEDGWOOD. Pascal Engel and I are in agreement about a number of crucial points:

DOXASTIC CORRECTNESS RALPH WEDGWOOD If beliefs are subject to a basic norm of correctness roughly, to the principle that a belief is correct only if the proposition believed is true how can this norm guide

### Introduction 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

### University of Groningen. Between "If" and "Then." Krzyzanowska, Karolina

University of Groningen Between "If" and "Then." Krzyzanowska, Karolina IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the

### Lecture 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

### Seeing Through The Veil of Perception *

Seeing Through The Veil of Perception * Abstract Suppose our visual experiences immediately justify some of our beliefs about the external world, that is, justify them in a way that does not rely on our

### Saying too Little and Saying too Much. Critical notice of Lying, Misleading, and What is Said, by Jennifer Saul

Saying too Little and Saying too Much. Critical notice of Lying, Misleading, and What is Said, by Jennifer Saul Umeå University BIBLID [0873-626X (2013) 35; pp. 81-91] 1 Introduction You are going to Paul

### How to Embed Epistemic Modals without Violating Modus Tollens

How to Embed Epistemic Modals without Violating Modus Tollens Joseph Salerno Saint Louis University, Saint Louis Jean Nicod Institute, Paris knowability@gmail.com May 26, 2013 Abstract Epistemic modals

### Saying too Little and Saying too Much Critical notice of Lying, Misleading, and What is Said, by Jennifer Saul

Saying too Little and Saying too Much Critical notice of Lying, Misleading, and What is Said, by Jennifer Saul Andreas Stokke andreas.stokke@gmail.com - published in Disputatio, V(35), 2013, 81-91 - 1

### Boghossian & 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

### Scepticism, Rationalism and Externalism

Scepticism, Rationalism and Externalism Brian Weatherson This paper is about three of the most prominent debates in modern epistemology. The conclusion is that three prima facie appealing positions in

### b) 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

### Semantic Minimalism and Nonindexical Contextualism

Semantic Minimalism and Nonindexical Contextualism John MacFarlane (University of California, Berkeley) Abstract: According to Semantic Minimalism, every use of "Chiara is tall" (fixing the girl and the

### MCQ 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 ------------.

### From Necessary Truth to Necessary Existence

Prequel for Section 4.2 of Defending the Correspondence Theory Published by PJP VII, 1 From Necessary Truth to Necessary Existence Abstract I introduce new details in an argument for necessarily existing

### How and How Not to Take on Brueckner s Sceptic. Christoph Kelp Institute of Philosophy, KU Leuven

How and How Not to Take on Brueckner s Sceptic Christoph Kelp Institute of Philosophy, KU Leuven christoph.kelp@hiw.kuleuven.be Brueckner s book brings together a carrier s worth of papers on scepticism.

### Why there is no such thing as a motivating reason

Why there is no such thing as a motivating reason Benjamin Kiesewetter, ENN Meeting in Oslo, 03.11.2016 (ERS) Explanatory reason statement: R is the reason why p. (NRS) Normative reason statement: R is

### DEFEASIBLE A PRIORI JUSTIFICATION: A REPLY TO THUROW

The Philosophical Quarterly Vol. 58, No. 231 April 2008 ISSN 0031 8094 doi: 10.1111/j.1467-9213.2007.512.x DEFEASIBLE A PRIORI JUSTIFICATION: A REPLY TO THUROW BY ALBERT CASULLO Joshua Thurow offers a

### Basic 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

### According to what Parsons (1984) has

AMERICAN PHILOSOPHICAL QUARTERLY Volume 38, Number 2, April 2001 FREE ASSUMPTIONS AND THE LIAR PARADOX Patrick Greenough I. OVERVIEW According to what Parsons (1984) has dubbed the Standard Solution of

### Are Some Modus Ponens Arguments Deductively Invalid?

Are Some Modus Ponens Arguments Deductively Invalid? DOUGLAS N. WALTON University of Winnipeg Abstract: This article concerns the structure of defeasible arguments like: 'If Bob has red spots, Bob has

### REDUCING REASONS JOURNAL OF ETHICS & SOCIAL PHILOSOPHY BY MATTHEW SILVERSTEIN VOL. 10, NO. 1 FEBRUARY 2016

BY MATTHEW SILVERSTEIN JOURNAL OF ETHICS & SOCIAL PHILOSOPHY VOL. 10, NO. 1 FEBRUARY 2016 URL: WWW.JESP.ORG COPYRIGHT MATTHEW SILVERSTEIN 2016 Reducing Reasons REASONS ARE CONSIDERATIONS THAT FIGURE in

### On Truth At Jeffrey C. King Rutgers University

On Truth At Jeffrey C. King Rutgers University I. Introduction A. At least some propositions exist contingently (Fine 1977, 1985) B. Given this, motivations for a notion of truth on which propositions

### An Inferentialist Conception of the A Priori. Ralph Wedgwood

An Inferentialist Conception of the A Priori Ralph Wedgwood When philosophers explain the distinction between the a priori and the a posteriori, they usually characterize the a priori negatively, as involving

### Safety, sensitivity and differential support

https://doi.org/10.1007/s11229-017-1645-z S.I.: THE EPISTEMOLOGY OF ERNEST SOSA Safety, sensitivity and differential support José L. Zalabardo 1 Received: 28 March 2017 / Accepted: 21 November 2017 The

### Validity of Inferences *

1 Validity of Inferences * When the systematic study of inferences began with Aristotle, there was in Greek culture already a flourishing argumentative practice with the purpose of supporting or grounding

### A Solution to the Gettier Problem Keota Fields. the three traditional conditions for knowledge, have been discussed extensively in the

A Solution to the Gettier Problem Keota Fields Problem cases by Edmund Gettier 1 and others 2, intended to undermine the sufficiency of the three traditional conditions for knowledge, have been discussed

### 2.3. Failed proofs and counterexamples

2.3. Failed proofs and counterexamples 2.3.0. Overview Derivations can also be used to tell when a claim of entailment does not follow from the principles for conjunction. 2.3.1. When enough is enough

### Squeezing arguments. Peter Smith. May 9, 2010

Squeezing arguments Peter Smith May 9, 2010 Many of our concepts are introduced to us via, and seem only to be constrained by, roughand-ready explanations and some sample paradigm positive and negative

### PHILOSOPHY 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

### tempered expressivism for Oxford Studies in Metaethics, volume 8

Mark Schroeder University of Southern California December 1, 2011 tempered expressivism for Oxford Studies in Metaethics, volume 8 This paper has two main goals. Its overarching goal, like that of some

### 9 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

### MODUS PONENS AND MODUS TOLLENS: THEIR VALIDITY/INVALIDITY IN NATURAL LANGUAGE ARGUMENTS

STUDIES IN LOGIC, GRAMMAR AND RHETORIC 50(63) 2017 DOI: 10.1515/slgr-2017-0028 Yong-Sok Ri Kim Il Sung University Pyongyang the Democratic People s Republic of Korea MODUS PONENS AND MODUS TOLLENS: THEIR

### Suppressed 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 real-life

### COMPARING CONTEXTUALISM AND INVARIANTISM ON THE CORRECTNESS OF CONTEXTUALIST INTUITIONS. Jessica BROWN University of Bristol

Grazer Philosophische Studien 69 (2005), xx yy. COMPARING CONTEXTUALISM AND INVARIANTISM ON THE CORRECTNESS OF CONTEXTUALIST INTUITIONS Jessica BROWN University of Bristol Summary Contextualism is motivated

### WHY WE REALLY CANNOT BELIEVE THE ERROR THEORY

WHY WE REALLY CANNOT BELIEVE THE ERROR THEORY Bart Streumer b.streumer@rug.nl 29 June 2017 Forthcoming in Diego Machuca (ed.), Moral Skepticism: New Essays 1. Introduction According to the error theory,

### Relevance. 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

### An argument against descriptive Millianism

An argument against descriptive Millianism phil 93914 Jeff Speaks March 10, 2008 The Unrepentant Millian explains apparent differences in informativeness, and apparent differences in the truth-values of

### 1.6 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

### Why Is a Valid Inference a Good Inference?

Philosophy and Phenomenological Research Philosophy and Phenomenological Research doi: 10.1111/phpr.12206 2015 Philosophy and Phenomenological Research, LLC Why Is a Valid Inference a Good Inference? SINAN

### 6: 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

### Epistemic Modals and Epistemic Modality

Epistemic Modals and Epistemic Modality Brian Weatherson and Andy Egan 1 Epistemic Possibility and Other Types of Possibility There is a lot that we don t know. That means that there are a lot of possibilities

### Some Unsound Arguments for Incompatibilism

Some Unsound Arguments for Incompatibilism Andrew M. Bailey Biola University December 2005 - 1-0. INTRODUCTION In this paper, I contend that several arguments for the incompatibility of determinism and

### Theories of propositions

Theories of propositions phil 93515 Jeff Speaks January 16, 2007 1 Commitment to propositions.......................... 1 2 A Fregean theory of reference.......................... 2 3 Three theories of

### ASSESSOR RELATIVISM AND THE PROBLEM OF MORAL DISAGREEMENT

The Southern Journal of Philosophy Volume 50, Issue 4 December 2012 ASSESSOR RELATIVISM AND THE PROBLEM OF MORAL DISAGREEMENT Karl Schafer abstract: I consider sophisticated forms of relativism and their

### Philosophy 5340 Epistemology Topic 4: Skepticism. Part 1: The Scope of Skepticism and Two Main Types of Skeptical Argument

1. The Scope of Skepticism Philosophy 5340 Epistemology Topic 4: Skepticism Part 1: The Scope of Skepticism and Two Main Types of Skeptical Argument The scope of skeptical challenges can vary in a number

### Pragmatic Considerations in the Interpretation of Denying the Antecedent

University of Windsor Scholarship at UWindsor OSSA Conference Archive OSSA 8 Jun 3rd, 9:00 AM - Jun 6th, 5:00 PM Pragmatic Considerations in the Interpretation of Denying the Antecedent Andrei Moldovan

### Do we have knowledge of the external world?

Do we have knowledge of the external world? This book discusses the skeptical arguments presented in Descartes' Meditations 1 and 2, as well as how Descartes attempts to refute skepticism by building our

### Some Counterexamples to Causal Decision Theory 1 Andy Egan Australian National University

Some Counterexamples to Causal Decision Theory 1 Andy Egan Australian National University Introduction Many philosophers (myself included) have been converted to causal decision theory by something like

### Two Paradoxes of Common Knowledge: Coordinated Attack and Electronic Mail

NOÛS 0:0 (2017) 1 25 doi: 10.1111/nous.12186 Two Paradoxes of Common Knowledge: Coordinated Attack and Electronic Mail HARVEY LEDERMAN Abstract The coordinated attack scenario and the electronic mail game

### CLASSIC INVARIANTISM, RELEVANCE, AND WARRANTED ASSERTABILITY MANŒUVERS

CLASSIC INVARIANTISM, RELEVANCE, AND WARRANTED ASSERTABILITY MANŒUVERS TIM BLACK The Philosophical Quarterly 55 (2005): 328-336 Jessica Brown effectively contends that Keith DeRose s latest argument for

### Consequentialism and Moral Rationalism

Forthcoming in Oxford Studies in Normative Ethics Consequentialism and Moral Rationalism DOUGLAS W. PORTMORE IN THIS PAPER, I make a presumptive case for moral rationalism: the view that agents can be

### What is Logical Validity?

What is Logical Validity? Whatever other merits proof-theoretic and model-theoretic accounts of validity may have, they are not remotely plausible as accounts of the meaning of valid. And not just because

### Epistemic two-dimensionalism and the epistemic argument

Epistemic two-dimensionalism and the epistemic argument Jeff Speaks November 12, 2008 Abstract. One of Kripke s fundamental objections to descriptivism was that the theory misclassifies certain a posteriori

### Denying 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

### Analogical Argument Schemes and Complex Argumentation

and Complex Argumentation ANDRÉ JUTHE Myrvägen 26 747 32 Alunda, Sweden Affiliation: University of Amsterdam, The Netherlands andre.juthe@gmail.com Abstract: This paper addresses several issues in argumentation

### Constructing the World

Constructing the World Lecture 1: A Scrutable World David Chalmers Plan *1. Laplace s demon 2. Primitive concepts and the Aufbau 3. Problems for the Aufbau 4. The scrutability base 5. Applications Laplace

### 1 Chapter 6 (Part 2): Assessing Truth Claims

1 Chapter 6 (Part 2): Assessing Truth Claims In the previous tutorial we saw that the standard of acceptability of a statement (or premise) depends on the context. In certain contexts we may only require

### Chapter 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 truth-value of a given truth-functional compound proposition depends

### Contradictory Information Can Be Better than Nothing The Example of the Two Firemen

Contradictory Information Can Be Better than Nothing The Example of the Two Firemen J. Michael Dunn School of Informatics and Computing, and Department of Philosophy Indiana University-Bloomington Workshop

### VARIETIES OF SKEPTICISM. Jonathan Vogel Amherst Collge and Harvard University

VARIETIES OF SKEPTICISM Jonathan Vogel Amherst Collge and Harvard University 1. Skepticism as an underdetermination problem Skepticism about the external world is a philosophical problem, but there are

### Denying the antecedent and conditional perfection again

University of Windsor Scholarship at UWindsor OSSA Conference Archive OSSA 10 May 22nd, 9:00 AM - May 25th, 5:00 PM Denying the antecedent and conditional perfection again Andrei Moldovan University of

### CRITICAL 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)

### Are Practical Reasons Like Theoretical Reasons?

Are Practical Reasons Like Theoretical Reasons? Jordan Wolf March 30, 2010 1 1 Introduction Particularism is said to be many things, some of them fairly radical, but in truth the position is straightforward.

### 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

### The distinction between truth-functional and non-truth-functional logical and linguistic

FORMAL CRITERIA OF NON-TRUTH-FUNCTIONALITY Dale Jacquette The Pennsylvania State University 1. Truth-Functional Meaning The distinction between truth-functional and non-truth-functional logical and linguistic

book symposium 651 Burge, T. 1986. Intellectual norms and foundations of mind. Journal of Philosophy 83: 697 720. Burge, T. 1989. Wherein is language social? In Reflections on Chomsky, ed. A. George, Oxford:

### Statistical 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:

### IN DEFENSE OF TRUTH-VALUE

CHAPTER 4 IN DEFENSE OF TRUTH-VALUE NTV owes much of its popularity, as well as its birth, to E.W. Adams --somewhat ironically, since his paper kicked off the contemporary literature on the truth conditions

### Theory of Knowledge. 5. That which can be asserted without evidence can be dismissed without evidence. (Christopher Hitchens). Do you agree?

Theory of Knowledge 5. That which can be asserted without evidence can be dismissed without evidence. (Christopher Hitchens). Do you agree? Candidate Name: Syed Tousif Ahmed Candidate Number: 006644 009

### McDowell and the New Evil Genius

1 McDowell and the New Evil Genius Ram Neta and Duncan Pritchard 0. Many epistemologists both internalists and externalists regard the New Evil Genius Problem (Lehrer & Cohen 1983) as constituting an important

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.

### Intrinsic Properties Defined. Peter Vallentyne, Virginia Commonwealth University. Philosophical Studies 88 (1997):

Intrinsic Properties Defined Peter Vallentyne, Virginia Commonwealth University Philosophical Studies 88 (1997): 209-219 Intuitively, a property is intrinsic just in case a thing's having it (at a time)

### Handout 2 Argument Terminology

Handout 2 Argument Terminology 1. Arguing, Arguments, & Statements Open Question: What happens when two people are in an argument? An argument is an abstraction from what goes on when people arguing. An

### THE TRANSMISSION OF KNOWLEDGE AND JUSTIFICATION

THE TRANSMISSION OF KNOWLEDGE AND JUSTIFICATION STEPHEN WRIGHT ABSTRACT. This paper explains how the notion of justification transmission can be used to ground a notion of knowledge transmission. It then

### Religious Experience. Well, it feels real

Religious Experience Well, it feels real St. Teresa of Avila/Jesus 1515-1582 Non-visual experience I was at prayer on a festival of the glorious Saint Peter when I saw Christ at my side or, to put it better,

### Responses to the sorites paradox

Responses to the sorites paradox phil 20229 Jeff Speaks April 21, 2008 1 Rejecting the initial premise: nihilism....................... 1 2 Rejecting one or more of the other premises....................