In: Anatomy and Physiology
Analyze each categorical proposition by doing the following:
Identify the subject term and predicate term of
each proposition; identify each categorical proposition (
A-proposition; E-proposition;
I-proposition; O-proposition);
identify the correct quantity ( universal or
particular); identify the correct quality (
affirmative or negative); identify the correct
distribution (subject term distributed; predicate term
distributed; both terms distributed; or neither term
distributed).
Categorical proposition 21
Some space heaters are not safe products.
Reference: Ref 5-21
The categorical proposition is an:
A. |
A-proposition |
|
B. |
E-proposition |
|
C. |
O-proposition |
|
D. |
I-proposition |
categorical proposition, or categorical statement, is a proposition that asserts or denies that all or some of the members of one category (the subject term) are included in another (the predicate term).
The Ancient Greeks such as Aristotleidentified four primary distinct types of categorical proposition and gave them standard forms (now often called A, E, I, and O). If, abstractly, the subject category is named S and the predicate category is named P, the four standard forms are:
Surprisingly, a large number of sentences may be translated into one of these canonical forms while retaining all or most of the original meaning of the sentence. Greek investigations resulted in the so-called square of opposition, which codifies the logical relations among the different forms; for example, that an A-statement is contradictory to an O-statement; that is to say, for example, if one believes "All apples are red fruits," one cannot simultaneously believe that "Some apples are not red fruits." Thus the relationships of the square of opposition may allow immediate inference, whereby the truth or falsity of one of the forms may follow directly from the truth or falsity of a statement in another form.