LOGIC 1 (EDUCTION) OBVERSE AND CONVERSE

EDUCTION

In an immediate inference, the conclusion is drawn from only one proposition. Eduction are those forms of immediate inference in which, from a given proposition we deduce another proposition differing from it in subject, in predicate on in both. The truth of the conclusion is implied by the truth of the premise.

There are seven kinds of eduction :

Two of these are fundamental and the remaining five are arrived the operation of there two kind. The basic eduction are conversion.

1)     Conversion :

Conversion is the position of terms in a proposition however logic is concerned only so far as the truth of the inferred proposition from the truth of the given proposition. Thus the conversion is the process of immediate inference in which from the given proposition we infer another proposition having the predicate of the original proposition as it subject and having the subject of the original proposition as its predicate. The position of the term in converse is

                 

ORIGINAL	S	P
CONVERSE	P	S

                       

ORIGINAL (CONVERTEND)		CONVERSE	SIMPLE OR AS PER ACCIDENT
A	ALL S IS P	SOME P IS S (I)	CONVERSE PER ACCIDENT
E	NO S IS P	NO P IS S (E)	SIMPLE CONVERSE
I	SOME S IS P	SOME P IS S (I)	SIMPLE CONVERSE
O	SOME S IS NOT P	NONE

                        Eg.:      Original          -           A- All husband are hen- pecked

                                    Converse        -           Some hen-pecked men are husband

                        Eg.:      Original          -           E – No ghost is beautiful

                                    Converse        -           No beautiful being is a ghost.

                        Eg.:      Original          -           I – some girls are as dark as Bipasha.

                                    Converse        -           Some beings as dark as Bipasha are girls.

2)     OBVERSION:

Obversion is the process of inference in which the subject of the inferred proposition is since as that of the original proposition but the predicate is contradictory of the original predicate. The quality of the proposition also changes. The given proposition is called the obvertant and the inferred proposition is called the obverse.

                       

                                   

ORIGINAL	S	P
CONVERSE	S	P

ORIGINAL (OBVERTEND)		OBVERSE
A	ALL S IS P	E	NO S IS NON – P
E	NO S IS P	A	ALL S IS NON – P
I	SOME S IS P	O	SOME S IS NOT NON – P
O	SOME S IS NOT P	I	SOME S IS NON – P

                                    Eg.:      Original          -           A – All journalist are pessimist.

                                                Obverse         -           E – No journalist are non pessimist.

                                                Original          -           E – No singers are good musicians.

                                                Obverse         -           All singers are non good musicians.

                                                Original          -           Some Indian are rich.

                                                Obverse         -           some Indian are non rich.

                                                Original          -           Some Americans are not blonde.

                                                Obverse         -           Some Americans are not non blonde.

SOLVE THE OBVERSE AND CONVERSE PROPOSITION (THE PROBLEM / SUMS ARE GIVEN ACCORDING TO THE PATTERN OF UNIVERSITY QUESTION PAPERS

Do as directed: 3

1) State the material obverse relation of

“ Men are strong . “

2) What is inference by converse relation of

„ X is younger than Y‟

3) What is the observe of

„Some eggs are rotten „

Reduce the sentence to logical form and state its obverse and converse “Every equilateral triangle is an

equiangular triangle.