Symbolic Logic Overview PDF
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This document provides an introduction to symbolic logic, including definitions, types of statements, logical connectives, and examples. It covers concepts like negation, conjunction, disjunction, conditional, and biconditional statements. Truth tables are also used to illustrate the concept of logical expressions.
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SYMBOLIC LOGIC OVERVIEW 2. Inverse: ∼p → ∼q 1. Definition: 3. Contrapositive: ∼q → ∼p o Symbolic Logic: A system using Example: "She is allowed to join the volleyb...
SYMBOLIC LOGIC OVERVIEW 2. Inverse: ∼p → ∼q 1. Definition: 3. Contrapositive: ∼q → ∼p o Symbolic Logic: A system using Example: "She is allowed to join the volleyball team only if symbols and variables to represent she knows how to receive the ball." statements and logical operations. Converse: If she knows how to receive the ball, o Statement: An assertion that is either then she is allowed to join the volleyball team. true or false. Inverse: If she does not know how to receive the 2. Types of Statements: ball, she is not allowed to join. o Simple Statement: Does not contain other statements as parts. Contrapositive: If she is not allowed to join, then she does not know how to receive the ball. o Compound Statement: Contains two or TRUTH TABLES more simple statements combined using logical connectives. A truth table summarizes the possible truth values of logical expressions. 3. Logical Connectives: o Negation (∼): "Not p" – Indicates the Negation: opposite truth value of p. o p | ∼p o Conjunction (∧): "p and q" – Both p and o T|F q must be true. o F|T o Disjunction (∨): "p or q" – Either p, q, or both must be true. Conjunction (p ∧ q): o Conditional (→): "If p, then q" – If p is o p|q|p∧q true, q must also be true. o T|T|T o Biconditional (↔): "p if and only if q" – p and q are both either true or false o T|F|F EXAMPLES OF COMPOUND STATEMENTS o F|T|F Given: o F|F|F h: Harry is not happy. Disjunction (p ∨ q): v: Harry is going to watch a volleyball game. o p|q|p∨q r: It is going to rain. o T|T|T s: Today is Sunday. o T|F|T Write the following: o F|T|T a: Today is Sunday and Harry is not happy → s ∧ o F|F|F ∼h b: Today is Sunday, and Harry is not going to COMPOUND STATEMENTS AND EQUIVALENCE watch volleyball → s ∧ ∼v Statements are equivalent if they have the same c: If it is going to rain, then Harry is not going to truth values. watch volleyball → r → ∼v Parentheses are used to clarify the order in which connectives are applied in compound statements. CONDITIONAL STATEMENTS AND THEIR FORMS Example Truth Table: Construct for (p ∨ q) ∧ ∼p. A conditional statement (p → q) has variations: 1. Converse: q → p PATTERNS OVERVIEW SYMMETRY 1. Definition: 1. Reflection Symmetry (Mirror Symmetry): o A pattern is a recurring, regular o A figure that can be divided into two structure or design found in nature, identical halves. human-made designs, or abstract ideas. Patterns can be modeled 2. Translation Symmetry: mathematically. o Repeated units that maintain the same o Investigating patterns helps establish figure, seen in natural structures like logical connections, make honeycombs. generalizations, predict future events, and possibly control outcomes. SEQUENCES 1. Arithmetic Sequence: KINDS OF PATTERNS o A sequence where the difference between consecutive terms is constant. 1. Patterns of Visuals: 2. Geometric Sequence: o Found in nature, like seeds, pinecones, branches, and leaves. o A sequence where the ratio between consecutive terms is constant. o Self-similar replication in plants such as 3. Harmonic Sequence: trees and ferns. 2. Patterns of Flow: o A sequence derived from the reciprocals of an arithmetic sequence. o Seen in the movement of water, the 4. Fibonacci Sequence: growth of trees, and meandering rivers. 3. Patterns of Movement: o Each term is the sum of the two preceding ones (e.g., 1, 1, 2, 3, 5, 8,...). o Rhythmic patterns in walking (left-right steps) and complex movements in THE GOLDEN RATIO animals and insects (horse walk, bird The Fibonacci sequence is closely related to the flight). Golden Ratio (approximately 1.618), which 4. Patterns of Rhythm: appears in natural patterns, architecture, and art. o Basic patterns like heartbeats or breathing, repetitive in nature, similar to the rhythm of a body’s internal processes. 5. Patterns of Texture: o Qualities we sense through touch, such as bristly, rough, smooth, or hard surfaces. 6. Geometric Patterns: o Repeated shapes in a predictable manner, like hexagonal patterns in honeycombs or patterns on cacti and succulents.