Transposition (p > q) : : ( ~ q > ~ p) Negate both statements

Slides:



Advertisements
Similar presentations
3.4 More on the Conditional
Advertisements

Proofs using all 18 rules, from Hurley 9th ed. pp Q > (F > A) 2. R > (A > F) 3. Q ∙ R / F ≡ A (J ∙ R) > H 2. (R > H) > M 3. ~(P v.
04 March 2009Instructor: Tasneem Darwish1 University of Palestine Faculty of Applied Engineering and Urban Planning Software Engineering Department Introduction.
1 Introduction to Abstract Mathematics Valid AND Invalid Arguments 2.3 Instructor: Hayk Melikya
Use a truth table to determine the validity or invalidity of this argument. First, translate into standard form “Martin is not buying a new car, since.
John Rosson Thursday February 15, 2007 Survey of Mathematical Ideas Math 100 Chapter 3, Logic.
2.2 Conditional Statements. Goals Identify statements which are conditional Identify the antecedent and consequent of a conditional statement Negate conditional.
Logic 2 The conditional and biconditional
Today’s Topics n Symbolizing conditionals and bi-conditionals n Other complex symbolizations. n Unless.
Logic 3 Tautological Implications and Tautological Equivalences
Syllabus Every Week: 2 Hourly Exams +Final - as noted on Syllabus
Propositional Logic. Negation Given a proposition p, negation of p is the ‘not’ of p.
Adapted from Discrete Math
CSCI2110 – Discrete Mathematics Tutorial 8 Propositional Logic Wong Chung Hoi (Hollis)
Propositions and Truth Tables
Propositions and Truth Tables. Proposition: Makes a claim that may be either true or false; it must have the structure of a complete sentence.
Mathematical Structures A collection of objects with operations defined on them and the accompanying properties form a mathematical structure or system.
7.4 Rules of Replacement II Trans, Impl, Equiv, Exp, Taut.
Philosophy 200 substitution rules. Substitution Sometimes, when you translate a statement from English to SL, you translate it in a form that is less.
DeMorgan’s Rule DM ~(p v q) :: (~p. ~q)“neither…nor…” is the same as “not the one and not the other” ~( p. q) :: (~p v ~q) “not both…” is the same as “either.
Mathematical Structures for Computer Science Chapter 1.2 Copyright © 2006 W.H. Freeman & Co.MSCS SlidesFormal Logic.
Today’s Topics Review of Sample Test # 2 A Little Meta Logic.
Transposition (p > q) : : ( ~ q > ~ p) Negate both statements when switching order of antecedent and consequent If the car starts, there’s gas in the tank.
Lecture Propositional Equivalences. Compound Propositions Compound propositions are made by combining existing propositions using logical operators.
 What are conditionals & biconditionals?  How do you write converses, inverses, and contrapositives?
Chapter Four Proofs. 1. Argument Forms An argument form is a group of sentence forms such that all of its substitution instances are arguments.
1 Introduction to Abstract Mathematics Expressions (Propositional formulas or forms) Instructor: Hayk Melikya
assumption procedures
Propositional Logic Symbolic logic If A, then B A  B Capital letters stand for simple sentences A simple sentence is an affirmative single statement “It’s.
Symbolic Logic ⊃ ≡ · v ~ ∴. What is a logical argument? Logic is the science of reasoning, proof, thinking, or inference. Logic allows us to analyze a.
Introduction to Logic Lecture 13 An Introduction to Truth Tables By David Kelsey.
Learning Objectives  To define a proposition  To form a compound proposition using connectives  To determine the truth values of compound propositions.
 To combine propositions using connectives  To construct the truth table of a given compound proposition  To define de Morgan Law for logic  To define.
Thinking Mathematically Logic 3.4 Truth Tables for the Conditional and Biconditional.
Discrete Mathematics Lecture # 4. Conditional Statements or Implication  If p and q are statement variables, the conditional of q by p is “If p then.
1.(p  q) 2. (r  s) 3. p v r  q v s 4. (p  q)  (r  s) conj. 1,2 5. q v sC.D. 3,4.
1 Introduction to Abstract Mathematics Proof Methods , , ~, ,  Instructor: Hayk Melikya Purpose of Section:Most theorems in mathematics.
Conditional statement or implication IF p then q is denoted p ⇒ q p is the antecedent or hypothesis q is the consequent or conclusion ⇒ means IF…THEN.
Today’s Topics Argument forms and rules (review)
1 Propositional Proofs 1. Problem 2 Deduction In deduction, the conclusion is true whenever the premises are true.  Premise: p Conclusion: (p ∨ q) 
Law of logic Lecture 4.
Simple Logic.
March 23 rd. Four Additional Rules of Inference  Constructive Dilemma (CD): (p  q) (r  s) p v r q v s.
Chapter 1 – Part 3 ELEMENTARY LOGIC
2. The Logic of Compound Statements Summary
CSNB 143 Discrete Mathematical Structures
Today’s Topics Symbolizing conditionals and bi-conditionals
Logic.
Natural Deduction: Using simple valid argument forms –as demonstrated by truth-tables—as rules of inference. A rule of inference is a rule stating that.
A v B ~ A B > C ~C B > (C . P) B / ~ B mt 1,2 / B ds 1,2
Double Negation p :: ~ ~p 1.A > ~ (B . C) 2. B . C ~ ~ ( H v K) ~ H
Information Technology Department
7.1 Rules of Implication I Natural Deduction is a method for deriving the conclusion of valid arguments expressed in the symbolism of propositional logic.
Chapter 3 Introduction to Logic © 2008 Pearson Addison-Wesley.
Chapter 3 Introduction to Logic 2012 Pearson Education, Inc.
Natural Deduction 1 Hurley, Logic 7.4.
Malini Sen WESTERN LOGIC Presented by Assistant Professor
Discrete Mathematics and Its Applications Kenneth H
1. (H . S) > [ H > (C > W)]
Natural Deduction Hurley, Logic 7.2.
Statements of Symbolic Logic
Section 3.3 Truth Tables for the Conditional and Biconditional
Section 2.2 Definitions and Biconditional Statement
Truth Tables for the Conditional and Biconditional
1.3 Propositional Equivalences
Natural Deduction Hurley, Logic 7.3.
Let Q be the question Let A be “the native is a knight”
Conditional Statements Section 2.3 GEOMETRY
Chapter 8 Natural Deduction
Truth Tables for Conditional and Biconditional Statements
Presentation transcript:

Transposition (p > q) : : ( ~ q > ~ p) Negate both statements when switching order of antecedent and consequent If the car starts, there’s gas in the tank :: If there’s no gas in the tank, the car won’t start

Implication (p > q) : : (~ p v q) Lets you replace a “v” with a “>” and vice versa, as long as you negate the first statement. If you want to get better at violin you have to practice : : either you don’t want to get better at violin or else you’ll practice. V > P ~V v P Either you register by Oct 4 or else you can’t vote : : If you don’t register by Oct 4, you can’t vote R v ~C ~R > ~C

Tautology (p v p) : : p (p . p) : : p Eliminates or introduces redundancies F > G F v G / G 3. ~F > G IMP 1 4. ~G > F TRANS 3 5. ~G > G HS 4,1 6. G v G IMP 5 7. G TAUT 6

Exportation [(p . q) > r] : : [( p > (q > r)] If two conditions together imply a statement, then if the one is true, then the other implies the statement, and vice versa. If Kerry wins Ohio and Pennsylvania, then he’ll win the election : : If Kerry wins Ohio, then if he wins Pennsylvania, then he’ll win the election

Material Equivalence EQ (p  q) : : [( p > q) . (q > p)] Biconditional interpretation “if and only if” means “necessary and sufficient condition for” ( p  q) : : [( p . q) v (~p . ~q)] Equivalency interpretation They are the same : : Either they are both true or they are both false They are the same : : Either both or neither

(P > R) . (R >P) P > Q R > (S . T) ~R > ~Q S > ( T > P) / P  R 5. Q > R TRANS 5 6. P > R HS 1,5 7. (S . T) > P EXP 4 8. R > P HS 2,7 9. (P > R) . (R > P) CONJ 6, 8 10. P  R EQ 9

1. A / ~B > A 2. A v B ADD 1 3. B v A COMM 2 4. ~B > A IMP 3

[p v (q .r)] :: [(p v q) . (p v r)] 7. 3 III, 24 (M .N) v ( O . P) (N v O) > ~P / N (M . N) v ( O . P) p v (q . r) 3. [(M . N) v O] . [( M . N) v P] DIST 1 4. (M . N) v O SIMP 3 5. O v ( M . N) COMM 4 6. (O v M) . (O v N) DIST 5 7. O v N COMM, SIMP 6 8. N v O COMM 7 9. ~ P MP 2,8 10 . (M . N) v P COMM, SIMP 3 11. M . N COMM, DS 9, 10 12. N COMM, SIMP 11