PRESENTATION

in

HUMANITIES 2

(LOGIC)

INVERSION

Short Review:What is CONVERSION?

-it is restraining the truth of the proposition by interchanging the subject and the predicate of the original proposition w/out over extending the quantity or either of the term.

What is OBVERSION?

- is a method of re-expressing truth by changing the quality of the copula so that the affirmative is rendered negative and the negative is rendered affirmative.

What is CONTRA POSITION?

- is a combination of conversion and obversion.

It has a interchangeable subject and predicate.

What is Inversion?

-it is the opposite of

obversion for it uses the

contradictory of the original

subject.

There are TWO (2) types of inversion.

1. First type is called PARTIAL or SIMPLE inversion. The quality is changed , but the predicate is the same as in the original proposition.

2. Second type is called COMPLETE inversion. The quality is unchanged, but the predicate is the contradictory of the original predicate.

Both types consist in the formulation of a new proposition whose subject is the contradictory of the original proposition.

The original proposition is called

the invertend, the new proposition the inverse, and the

process itself inversion.

Steps in Inversion

Simple or Partial

Proposition New proposition.

Subject Use the contradictory of the subject .

Copula Change

Predicate Put the original predicate.

Proposition New Proposition.

Subject Use the contradictory of the subject.

Copula Do not change.

Predicate Use the contradictory of the predicate.

Complete

Models of Inversion

Model in Type 1 (PARTIAL or SIMPLE)

A to O

I to E

A (Affirmative & either universal or singular )

O (Negative & particular)

I (Affirmative & Particular)

E (Negative & Universal or Singular)

NOTE:

Models in Type 2 (COMPLETE)

A to I

E to O

A (Affirmative & either universal or singular )

I (Affirmative & Particular)

E (Negative & Universal or Singular)

O (Negative & particular)

NOTE:

Another type is the OBSERVE of Type 1,

and is therefore sometimes called the “obverted inverse,” as opposed to Type 1

which is called the “simple inverse”.

Examples!!

If you subject an A proposition to the following processes, you

finally get its inverse.

INVERTEND: A. Every S is a P. (“Every cat is an animal.”)

Obvert to: E. No S is a non-P. (“No cat is a non-animal.”)

Convert to: E. No non-P is an S. (“No non-animal is a cat.”)

Obvert to: A. Every non-P is a non-S. (“Every non-animal

is a non-cat”)

Convert to: I. Some non-S is a non-P. (“Some non-cat is non-animal”) => This is inverse, Type 2

Obvert to: O. Some non-S is not a P. (“Some non-cat is not an animal.”) => This is inverse, Type 1

If you subject an E proposition to the following processes, you finally get its inverse. Note that you must convert

first and then obvert.

INVERTEND: E. no S is P. (“No cat is a dog.”)

Convert to: E. No P is an S. (“No dog is a cat.”)

Obvert to: A. Every P is a non-S. (“Every dog is a non- cat.”)

Convert to: I. Some non-S is a P. (“Some non-cat is a dog”) => This is inverse, Type 1

Obvert to: O. Some non-S is non-P. (“Some non-cat is not a non-dog.”) => This is inverse, Type 2

Remember:

The value of studying

inversion lies principally in

the facility it gives us in

recognizing quantitative

relationship of the subject

and predicate. ^-^

The END!!

Submitted by:Group 8

Leader: Orlaine Gamilla

Secretary: Jelyan Garanganao

Members:

Hanjie Sales

Carmela Joy Serantes

Jenalyn Villarosa

Submitted to:Mr. Ursecio Inodeo

For

Watching!!