Discover millions of ebooks, audiobooks, and so much more with a free trial

From $11.99/month after trial. Cancel anytime.

Popular Lectures on Logic
Popular Lectures on Logic
Popular Lectures on Logic
Ebook103 pages1 hour

Popular Lectures on Logic

Rating: 0 out of 5 stars

()

Read preview

About this ebook

Crisp, easy-to-understand lectures on logic.

Table of contents:

30 Principles of Logic
Mathematical Logic
Trilingual Logic
101 Principles of Logic
Different kinds of Mathematical Functions: A Dialogue
Fucntions, Bijections and Mapping-relations
Logic and Formal Truth
Relations and Ordinal Numbers
Nine Kinds of Number
Causality
Analyticity
Is Mind an Emergent Property?
Is Time-travel Possible?
What is a Formal Language?
Logic and Inference

LanguageEnglish
Release dateDec 21, 2019
ISBN9781393371373
Popular Lectures on Logic
Author

John-Michael Kuczynski

J.-M. Kuczynski, PhD University of California, Professor (philosophy, mathematics, economics) at Bard, SBCC, and VCU. Award-winning author turned cyber-preneur. In Who's Who in the World since 2002. 1-800-969-6596 to get started right away.

Read more from John Michael Kuczynski

Related to Popular Lectures on Logic

Related ebooks

Mathematics For You

View More

Related articles

Reviews for Popular Lectures on Logic

Rating: 0 out of 5 stars
0 ratings

0 ratings0 reviews

What did you think?

Tap to rate

Review must be at least 10 words

    Book preview

    Popular Lectures on Logic - John-Michael Kuczynski

    30 Principles of Logic

    Excluded Middle

    p or not p

    Either Jim has two cars or Jim does not have two cars. Non-contradiction

    Not both p and not p

    Jim does not both have and not have two cars. Modus Ponens

    If p, and if p entails q, then q.

    If Jim has two cars, and if Jim’s being happy follows from his having two cars, then Jim is happy

    Note: To say that p entails q is to say that q follows from p. Modus Tollens

    If not q, and if p entails q, then not-p.

    If Jim is unhappy, and if Jim’s being happy follows from his having two cars, then Jim does not have two cars

    Contraposition

    p entails q is equivalent with not q entails not p.

    For x is a raven to entail that x is black is for x is non-black to entail that x is a non-raven.

    Double Negation

    p if, and only if, not not p.

    Any given statement is equivalent with the negation of its own negation. Jim has two cars if, and only if, Jim does not not have two cars.

    Note: to say that two statements are equivalent is to say that each entails the other.

    Simplification

    If p and q, then p.

    If Jim has two cars and bill is over 7 ft tall, then jim has two cars Logical Addition

    If p, then either p or q.

    If Jim has two cars, then either Jim has two cars or Bill is over 7 ft tall Additive Identity

    If p, then either p or p.

    If Jim has two cars, then either Jim has two cars or Jim has two cars Multiplicative identity

    If p, then p and p.

    If Jim has two cars, then Jim has two cars and Jim has two cars Transitivity

    If p entails q and q entails r, then p entails r.

    p: Jim has exactly two cars

    q: Jim has an even prime number of cars. r: Jim has a prime number of cars.

    p entails q. q entails r. p entails r.

    Self-equivalence

    p if, and only if, p.

    Any given statement is equivalent with itself.

    Contraction

    p or not-p follows from q.

    No statement does not entail a tautology. Expansion

    If p entails both q and not q, then p is false.

    x is a four-sided triangle entails x has and does not have more than three sides. Therefore, it is false that x is a three-sided triangle

    This law is a consequence of the Law of Non-contradiction, taken in conjunction with modus tollens. it is therefore a derived law

    Generalized Expansion

    If q is a law of logic and p entails not-q, then p is false.

    Explanation: If q is a truth of logic, then q holds in all possible worlds. Therefore, not-q is false in all possible worlds. Therefore, by modus tollens, anything that entails q is false in all possible worlds.

    ––––––––

    Consistency

    If p entails not-p, then not-p.

    No truth is inconsistent with itself.

    p: x is a round square

    q: x has exactly three sides.

    p entails q.

    p also entails not-q.

    Therefore, p entails both q and not-q.

    Given the law of non-contradiction, q and not-q is false. Therefore, by modus tollens, p is false.

    Boolean Modus Ponens

    If all f’s are g’s, then if x is an f, x is also a g.

    This law is an analogue of modus ponens. what modus ponens says about statements, this law says about classes.

    Boolean Modus Tollens

    If all f’s are g’s, then if x is a non-g, x is a non-f

    This law is an analogue of modus tollens. what modus tollens says about statements, this law says about classes.

    Identity of Indiscernibles

    Objects are identical when the same.

    If there is no characteristic that x has that y does not have and no characteristic that y has that x does not have, then x=y

    Indiscernibility of Identicals

    Objects are the same when identical.

    If x and y are the very same object, then there is no characteristic x has that y does not have and no characteristic that y has that x does not have.

    Actuality of Necessity

    What is necessary is actual.

    In other words, if p must be true, then p is true.

    Squares must have four sides; therefore, squares do have four sides.

    Explanation: p is necessarily true if p is true in all possible worlds. if p is true in all possible worlds, then p is true in this world.

    Possibility of Actuality

    What is actual is possible

    In other words, if p is true, then p can be true.

    This law follows from the previous two. Duality (Version 1)

    If p is necessarily true, then not-p is necessarily false.

    Squares have four sides is necessarily true. Therefore, squares do not have four sides is necessarily false.

    Duality (Version 2)

    If p is possible, then p is not necessarily false.

    Jim has two cars is possible. Therefore, Jim has two cars is not necessarily false.

    S5

    If p is unconditionally true, then it is unconditionally the case that p is unconditionally true. Given that squares have four sides is unconditionally true, it follows that squares have four sides is unconditionally true is unconditionally true.

    Distributivity of Necessity

    If p is necessarily true and q is necessarily true, then p and q is necessarily true.

    p: Squares have four sides q: Triangles have three sides

    p is necessarily true, and so is q. Therefore, it is necessarily the case that both p and q. Non-distributivity of Possibility

    Given only that p is possible and that q is possible, it does not follow that they are jointly possible.

    In other words, p and q is possible does not follow from p is possible and q is possible

    p: Jim has more than two cars q: Jim has less than two cars.

    p and q is not possible, even though p is possible and q is possible. Extrusion

    If q is a contradiction, then p or q is equivalent with p.

    Either Jim is wealthy or Squares have three sides is equivalent with Jim is wealthy.

    Absorption

    If q is a tautology, then p and q is equivalent with p.

    Jim is wealthy and Squares have four sides is equivalent with Jim is wealthy. Promiscuity of Necessity

    If p is necessary, then q entails p, for any q.

    Given that squares have four sides is necessary, there is no truth and no falsehood that does not entail it.

    Explanation: If p is necessary, there is no world where not-p is true and a fortiori no world where

    Enjoying the preview?
    Page 1 of 1
    pFad - Phonifier reborn

    Pfad - The Proxy pFad of © 2024 Garber Painting. All rights reserved.

    Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.


    Alternative Proxies:

    Alternative Proxy

    pFad Proxy

    pFad v3 Proxy

    pFad v4 Proxy