Three Acts of the Mind Mental Act: Verbal Expression: Simple - PDF document

Three Acts of the Mind Mental Act: Verbal Expression: • Simple Apprehension • Term • Judgment • Proposition • Deductive Inference • Syllogism Slide 5-1 The Four Logical Statements The four logical statements The quantifier Quality Quantity Distinguishing universal statements Slide 5-2 1

Judgment is the act by which the intellect unites by affirming , or separates by denying . Slide 5-3 The classification of propositions Slide 5-4 2

The Four Statements of Logic: A: All S is P I: Some S is P E: No S is P O: Some S is not P Slide 5-5 affirmo The A statement affirms something about all of S, namely, P. All S is P Slide 5-6 3

Examples of A Statements All men are mortal All cars are fast All boys are rude All girls are pretty Slide 5-7 affirmo The I statement affirms something about some S’s, namely P. Some S is P Slide 5-8 4

Examples of I Statements Some men are mortal Some cars are fast Some boys are rude Some girls are pretty Slide 5-9 nego The E statement denies something about all S, namely P. No S is P Slide 5-10 5

Examples of E Statements No men are mortal No cars are fast No boys are rude No girls are pretty Slide 5-11 nego The O statement denies something about some S’s, namely P. Some S is not P Slide 5-12 6

Examples of O Statements Some men are not mortal Some cars are not fast Some boys are not rude Some girls are not pretty Slide 5-13 The Four Elements of a Proposition Quantifier Subject-term Predicate-term Copula Slide 5-14 7

The Four Kinds of Quantifier All Some No Some … not Slide 5-15 The Quality of a Proposition affirmative negative Slide 5-16 8

Affirmative Propositions A: All men are mortal I: Some men are happy Slide 5-17 Negative Propositions E: No men are gods O: Some men are not happy Slide 5-18 9

The Quantity of Propositions Universal Particular Slide 5-19 Universal Propositions A: All men are mortal E: No men are gods Slide 5-20 10

Quantity and Quality of Quantity and Quality of the Four Categorical the Four Categorical Statements Statements Quality Affirmative Negative Universal A E Quantity Particular I O Slide 5-21 Particular Propositions I: Some men are happy O: Some men are not happy Slide 5-22 11

Quantity and Quality of Quantity and Quality of the Four Categorical the Four Categorical Statements Statements Quality Affirmative Negative Universal A E Quantity Particular I O Slide 5-23 Distinguishing Universal Statements The general rule is that, in statements that do not contain a quantifier, all is intended unless some is clearly indicated. Slide 5-24 12

Distinguishing Universal Statements Frogs are ugly = All frogs are ugly BUT Men are setting sail = Some men are setting sail Slide 5-25 Terms in which the subject is an individual are universal Socrates is a man Slide 5-26 13

The Four Logical Statements The four logical statements The quantifier Quality Quantity Distinguishing universal statements Slide 5-27 14