Arguments with Quantified Statements M260 3.4. Universal Instantiation If some property is true for everything in a domain, then it is true of any particular.

Slides:



Advertisements
Similar presentations
Rules of Inferences Section 1.5. Definitions Argument: is a sequence of propositions (premises) that end with a proposition called conclusion. Valid Argument:
Advertisements

1 Valid and Invalid arguments. 2 Definition of Argument Sequence of statements: Statement 1; Statement 2; Therefore, Statement 3. Statements 1 and 2 are.
The Foundations: Logic and Proofs
DISCRETE MATHEMATICS I LECTURES CHAPTER 3 Dr. Adam P. Anthony Spring 2011 Some material adapted from lecture notes provided by Dr. Chungsim Han and Dr.
Valid Arguments An argument is a sequence of propositions. All but the final proposition are called premises. The last statement is the conclusion. The.
Discrete Maths 4. Proofs Objectives
Chapter 1 The Logic of Compound Statements. Section 1.3 Valid & Invalid Arguments.
CS128 – Discrete Mathematics for Computer Science
Chapter 1 The Logic of Compound Statements. Section 1.2 – 1.3 (Modus Tollens) Conditional and Valid & Invalid Arguments.
Discrete Mathematics Lecture 2 Logic of Quantified Statements,
Discrete Mathematics Lecture 2 Alexander Bukharovich New York University.
Essential Deduction Techniques of Constructing Formal Expressions and Evaluating Attempts to Create Valid Arguments.
Predicate Calculus Subject / Predicate John / went to the store. The sky / is blue. Propositional Logic - uses statements Predicate Calculus - uses predicates.
Essential Deduction Techniques of Constructing Formal Expressions Evaluating Attempts to Create Valid Arguments.
Copyright © Cengage Learning. All rights reserved.
Discrete Structures Chapter 3: The Logic of Quantified Statements
Harper Langston New York University Summer 2015
Copyright © Curt Hill Rules of Inference What is a valid argument?
CSCI 115 Chapter 2 Logic. CSCI 115 §2.1 Propositions and Logical Operations.
 Predicate: A sentence that contains a finite number of variables and becomes a statement when values are substituted for the variables. ◦ Domain: the.
Week 3 - Monday.  What did we talk about last time?  Predicate logic  Multiple quantifiers  Negating multiple quantifiers  Arguments with quantified.
Week 2 - Friday.  What did we talk about last time?  Predicate logic  Negation  Multiple quantifiers.
(CSC 102) Lecture 7 Discrete Structures. Previous Lectures Summary Predicates Set Notation Universal and Existential Statement Translating between formal.
Chap. 2 Fundamentals of Logic. Proposition Proposition (or statement): an declarative sentence that is either true or false, but not both. e.g. –Margret.
Chapter 2 The Logic of Quantified Statements. Section 2.4 Arguments with Quantified Statements.
Chapter 1 Logic Section 1-1 Statements Open your book to page 1 and read the section titled “To the Student” Now turn to page 3 where we will read the.
Section 1.5. Section Summary Nested Quantifiers Order of Quantifiers Translating from Nested Quantifiers into English Translating Mathematical Statements.
1 Sections 1.5 & 3.1 Methods of Proof / Proof Strategy.
Predicates and Quantified Statements M , 3.2.
2.3Logical Implication: Rules of Inference From the notion of a valid argument, we begin a formal study of what we shall mean by an argument and when such.
Fundamentals of Logic 1. What is a valid argument or proof? 2. Study system of logic 3. In proving theorems or solving problems, creativity and insight.
(CSC 102) Lecture 8 Discrete Structures. Previous Lectures Summary Predicates Set Notation Universal and Existential Statement Translating between formal.
Predicates and Quantified Statements
Chapter 2 The Logic of Quantified Statements. Section 2.1 Intro to Predicates & Quantified Statements.
CompSci 102 Discrete Math for Computer Science January 24, 2012 Prof. Rodger Slides modified from Rosen.
1 Introduction to Abstract Mathematics Chapter 2: The Logic of Quantified Statements. Predicate Calculus Instructor: Hayk Melikya 2.3.
Valid and Invalid Arguments
4.1 Proofs and Counterexamples. Even Odd Numbers Find a property that describes each of the following sets E={…, -4, -2, 0, 2, 4, 6, …} O={…, -3, -1,
Lecture 7 – Jan 28, Chapter 2 The Logic of Quantified Statements.
1 CMSC 250 Chapter 2, Predicate Logic. 2 CMSC 250 Definitions l Subject / predicate John / went to the store. The sky / is blue. l Propositional logic-
Chapter 2 Fundamentals of Logic 1. What is a valid argument or proof?
Dilemma: Division Into Cases Dilemma: p  q p  r q  r  r Premises:x is positive or x is negative. If x is positive, then x 2 is positive. If x is negative,
Arguments with Quantified Statements Lecture 10 Section 2.4 Thu, Jan 27, 2005.
Week 4 - Friday.  What did we talk about last time?  Floor and ceiling  Proof by contradiction.
1 Chapter 2.1 Chapter 2.2 Chapter 2.3 Chapter 2.4 All images are copyrighted to their respective copyright holders and reproduced here for academic purposes.
Lecture 041 Predicate Calculus Learning outcomes Students are able to: 1. Evaluate predicate 2. Translate predicate into human language and vice versa.
Logic: The Language of Philosophy. What is Logic? Logic is the study of argumentation o In Philosophy, there are no right or wrong opinions, but there.
Discrete Mathematical Structures: Theory and Applications 1 Logic: Learning Objectives  Learn about statements (propositions)  Learn how to use logical.
Week 2 - Friday.  What did we talk about last time?  Predicate logic  Negation  Multiple quantifiers.
Deductive Reasoning. Inductive: premise offers support and evidenceInductive: premise offers support and evidence Deductive: premises offers proof that.
Discrete Mathematics Lecture 2 Continuing Logic, Quantified Logic, Beginning Proofs Harper Langston New York University Summer 2016.
Harper Langston New York University Summer 2017
3. The Logic of Quantified Statements
Arguments with Quantified Statements
2. The Logic of Compound Statements Summary
3. The Logic of Quantified Statements Summary
Chapter 3 The Logic of Quantified Statements
Negations of Quantified Statements
CHAPTER 3 THE LOGIC OF QUANTIFIED STATEMENTS.
Copyright © Cengage Learning. All rights reserved.
Logical Inferences: A set of premises accompanied by a suggested conclusion regardless of whether or not the conclusion is a logical consequence of the.
3.5 Symbolic Arguments.
Copyright © Cengage Learning. All rights reserved.
Predicates and Quantifiers
Discrete Mathematics Lecture 4 Logic of Quantified Statements
CPSC 121: Models of Computation
Phil2303 intro to logic.
If there is any case in which true premises lead to a false conclusion, the argument is invalid. Therefore this argument is INVALID.
Introduction to Proofs
If there is any case in which true premises lead to a false conclusion, the argument is invalid. Therefore this argument is INVALID.
Presentation transcript:

Arguments with Quantified Statements M

Universal Instantiation If some property is true for everything in a domain, then it is true of any particular thing in the domain.

Example All human beings are mortal. Socrates is a human being. Therefore Socrates is mortal.

Simplify r k+1 r r k+1 r = r k+1 r 1 = r (k+1)+1 = r k+2 Uses universal truths

Universal Modus Ponens For all x, if P(x) then Q(x) P(a) for a particular a Therefore Q(a)

Example If a number is even, then its square is even. K is a particular number that is even Therefore k 2 is even.

Formal version hummm

Prove that the sum of two even integers is even do it here

Universal Modus Tollens For all x, if P(x) then Q(x). ~Q(a) for some particular a Therefore ~P(a)

Example All human beings are mortal. Zeus is not mortal. Therefore Zeus is not a human being.

Valid Argument Form No matter what predicates are substituted for the predicate symbols in the premises, if the premise statements are all true then the conclusion is also true. An argument is valid if its form is valid.

Use Diagrams for Zeus and Felix All human beings are mortal. Zeus is not mortal. Therefore Zeus is not a human being.

Use Diagrams for Zeus and Felix All human beings are mortal. Felix is mortal. Therefore Felix is a human being.

Converse Error For all x, if P(x) then Q(x). Q(a) for a particular a. Therefore P(a) INVALID

Inverse Error For all x, if P(x) then Q(x). ~P(a) for a particular a. Therefore ~Q(a) INVALID

No No polynomials have horizontal asymptotes This function has a horizontal asymptote. Therefore this function is not a polynomial

Rewrite For all x, if x is a polynomial, then x does not have a horizontal asymptote. Use Universal Modus Tollens.