1. Religion & Spirituality
categorical proposition
<Back to Last Page >     <Glossary Index>

 Related Terms
• proposition

 

Definition:
A categorical proposition is a proposition which relates two classes to each other (through a direct assertion of agreement or disagreement between them), both of which are delineated with a categorical term. There are only four forms of a categorical proposition:

All S are P.
No S are P.
Some S are P.
Some S are not P.

The first, All S are P, is a universal affirmative. The second, No S are P, is a universal negative. The third, Some S are P, is a particular affirmative. The fourth, Some S are not P, is a particular negative.

The classes are represented by the letters, S and P. The categorical terms are the quantifiers: All, No, Some.

Categorical propositions are usually divided up into four groups: A, E, I and O:

A: All S are P (One category is a subset of another)
E: No S are P (The two categories do not intersect)
I: Some S is/are P (The two categories intersect)
O: Some S is/are not P (One category is not a subset of another)

A key issue is the nature of distribution. A category is said to be distributed if the proposition refers to every member of the category. The first term is distributed in A propositions; the second is distributed in O propositions; both are distributed in E propositions; and none are distributed in I propositions.

One distinguishing feature of categorical propositions is quantity:

  1. Universal propositions (A, E) refer to all members of the class designated by its subject term.
  2. Particular propositions (I, O) refer just to some members of the class designated by its subject term.

Another distinguishing feature of categorical propositions is quality:

  1. Affirmative propositions (A, I) express a relationship of inclusion between members of the classes designated by its terms.
  2. Negative propositions (E, O) express a relationship of exclusion between members of the classes designated by its terms.

Also Known As: none

Alternate Spellings: none

Common Misspellings: none

Related Resources:

What is the Logic and the Philosophy of Language?
The two fields Logic and the Philosophy of Language are often treated separately, but they are nevertheless close enough that they are presented together here. Logic is the study of methods of reasoning and argumentation, both proper and improper. The Philosophy of Language, on the other hand, involves the study of how our language interacts with our thinking.

What is Philosophy?
What is philosophy? Is there any point in studying philosophy, or is it a useless subject? What are the different branches of philosophy - what's the difference between aestheitcs and ethics? What's the difference between metaphysics and epistemology?

<Back to Last Page >     <Glossary Index>
You can opt-out at any time. Please refer to our privacy policy for contact information.

Discuss in my forum

©2014 About.com. All rights reserved.