This document provides an introduction to logic, including definitions of key terms like inference, proposition, and truth values. It gives examples of valid logical inferences and explains the basic elements of a proposition - the subject, predicate, and copula. The document also discusses different types of propositions such as categorical, conditional, and disjunctive and provides exercises for identifying subjects, predicates, and copulas in sample propositions.

1. Introduction to Logic
1

2. Outline of Today’s Lecture
 What Logic is
 Inference
 Proposition
 Truth Values
 Type of Propositions
2

3. Examples
All men are mortal.
Socrates is a man.
Therefore Socrates is mortal.
All dogs are animals.
No cats are dog.
Therefore no cats are animals.
3

4. Logic
“Logic is the study of the general
conditions of valid inference (or
of proof).”
4

5. Inference
 “An inference is an inferred
judgment, that is, a judgment drive
from another judgment, or from other
judgments.”
5

6. Examples
1. It seems cloudy outside.
So it might be raining today.
2. It seems cloudy outside.
It might be raining today.
So I should carry my umbrella.
6

7. PROPOSITION
“A judgment of belief when
expressed in language is
commonly called a
proposition.”
 All propositions are either true or false.
7

8. Examples of propositions
 Grass is green.
 The Moon is made of green cheese.
 Sacramento is the capital of California.
8

9. Examples that are not propositions
 Sit down!
 What time is it?
9

10. Three basic elements of an
attributive proposition:
 Subject
 Predicate
 Copula
10

11. Example
Sakib is a cricket player.
Copula
Subject Predicate
11

12. Copula
 Is
 Am
 Are
 Is not
 Am not
 Are not
12

13. S is p.
S+C+P
13

14. Exercise
1. The moon is made of green cheese.
2. Study logic more often, please.
3. The largest state in the United States was once an independent
republic.
4. Cars are useful.
5. Yay, Cardinals!
6. What time is it?
7. The bone was for the dog.
8. The sun is above the clouds.
9. Grass is green.
10. How nice the bird is!
Please find out the proposition, and determine their subject term,
copula and predicate term
14

15. Type of Propositions
 Categorical Proposition
 Conditional or Hypothetical Proposition
 Disjunctive Proposition
15

16. 16
Thank You