Standard Form

Because there are two possible qualities and two possible quantities, there are just four standard logical forms for categorical propositions, no matter how complex their subject and predicate terms may be. These four forms are:

AFFIRMATIVE
NEGATIVE
UNIVERSAL
A: All S are P E: No S is P
PARTICULAR
I: Some S are P O: Some S are not P
The letters A, E, I, and O are the traditional labels for the four standard forms.


Comprehension Questions

1 Is the following proposition universal or particular?
Not any of you came to my assistance.
a) universal
b) particular
2 Is the following proposition universal or particular?
Not every cow is brown.
a) universal
b) particular
3 Is the following proposition universal or particular?
Three out of four dogs prefer DogTime Treats.
a) universal
b) particular
4 Is the following proposition affirmative or negative?
All noble deeds are rare.
a) affirmative
b) negative
5 Is the following proposition affirmative or negative?
Some nondogs are cats.
a) affirmative
b) negative
6 Is the following proposition affirmative or negative?
Some living things are nonplants.
a) affirmative
b) negative
7 What kind of proposition is the following?
No man is an island.
a) universal affirmative (A)
b) universal negative (E)
c) particular affirmative (I)
d) particular negative (O)
8 What kind of proposition is the following?
Every general is fighting the previous war.
a) universal affirmative (A)
b) universal negative (E)
c) particular affirmative (I)
d) particular negative (O)
9 What kind of proposition is the following?
Some liars can fool all of the people.
a) universal affirmative (A)
b) universal negative (E)
c) particular affirmative (I)
d) particular negative (O)
10 What kind of proposition is the following?
Some who are famous are not infamous.
a) universal affirmative (A)
b) universal negative (E)
c) particular affirmative (I)
d) particular negative (O)


Square of Opposition

© Copyright 1998, W.W. Norton & Co.