Phi002-Lesson 9
Phi002-Lesson 9
Phi002-Lesson 9
Teachers’ Guide
Lesson 9
A. Productivity
LESSON PREVIEW/REVIEW
Tip:
Hey there! Today! You are about to learn Logical opposition. Often, we find ourselves making
1) Introductionconclusions
(2 mins) about what can no longer be true because of what we already know about certain things.
Besides, at times, we find ourselves confronted with two statements which seem to either prove or
disprove the truth of SQUARE OF
each other. This OPPOSITIONS
judgement is called oppositional inference. Let’s get to know
more! Have a Good day!
Section:
Direction: Using the diagram of the Square of Oppositions above, identify what type of opposition the following
pair/relation of propositions. Write your answers on the “What I Know” column.
B. MAIN LESSON
Logical Opposition/ Aristotelian Square–it refers to the relationship existing between two proposition having the same subject
and the same predicate but differ in quantity or in quality or both quantity or quality. Simply, it refers to the relationship
among A, E, I propositions, and O.
Section:
Kinds of Opposition
1. Contradiction –Propositions having the same subject term and same predicate term but are different in both about their
quality and quantity.
Rules of Contradictories:
If one is true, the other is false.
If one is false, the other is true.
2. Contrary – when proposition have the same subject term, the same predicate term, and are all of universal qualities
yet are different in quality.
Rules of Contrary:
If one is true, the other is false.
If one is false, the other is doubtful.
Both can be false at the same time, but never true at the same time.
2) Activity 3.1: Skill-building Activities (with answer key) (18 mins + 2 mins checking)
Direction: Give the contradictory and contrary proposition of the following by changing the given statements
below.
Ex. All monkeys are primate. Some monkeys are not primate. No monkeys are primate.
No whales are reptiles. Some whales are reptiles. All whales are reptiles
No Christians are Muslims. Some Christians are Muslims. All Christians are Muslims.
All police are arrogant. Some police are not arrogant. No police are arrogant.
No Cocians are Ateneans. Some Cocians are Ateneans. All Cocians are Ateneans.
Activity 3.2: Skill-building Activities (with answer key) (18 mins + 2 mins checking)
Section:
Directions:
A B C
E
A B C
A
Direction: Provide two examples of Oppositions and apply the rules of contradictory.
Rule # 1 A-O Ex. If every Filipino is Asian (TRUE), then some Filipino are not Asian (False).
Rule # 2 I-E Ex. If some cows are writers (FALSE), then no cows is a writer (True).
Section:
Directions: Give the contradictory and contrary opposites to each of the following propositions; and if the
original proposition is true, state whether its opposition is true, false, or doubtful.
2. No man is an island.
C. LESSON WRAP-UP
You are done with the session! Let's track your progress