Logical Reasoning and Syllogisms to find correct Conclusions

Tuesday, March 21, 2017

The word 'Logic' is derived from the Greek term 'logos' meaning both 'thought' and 'the word expressing thought'. That means logic is the science of expressing thoughts in the form of language/statements.

Statements :-

  • Statements are the propositions about something or someone(Subject).
There are 3 parts of any statement in Syllogism :-
  1. Subject :- This is the one about which something is said.
  2. Predicate :- This is the quality or properties of Subject.
  3. Copula :- This is the connective word of Subject and Predicate.
All fans are chairs.
{1. All fans = Subject(S), 2. Chairs = Predicate(P), 3. are = Copula}

Classification of Statements:-

Statements are further classified in 4 parts:-
  1. Universal Affirmative Statement{All(S) are (P)} :- The statement in which subject is distributed but predicate is not distributed.       Example:- All roses are marigolds.
  2. Universal Negative Statement{No(S) are (P)} :- The statement in which both subject and predicate are distributed is known as Universal Negative Statement.         Example:- No roses are marigolds.
  3. Particular Affirmative Statement{Some(S)are (P)} :- In this type of statement non of the subject or predicate is distributed. Example:- Some roses are roses.
  4. Particular Negative Statement {Some(S) are not (P)} :- These statements in which only predicate is distributed but subject is not.   Example:- Some roses are not marigolds.
  • Syllogism is a topic in which we have to derive conclusions from two statements called as

  • Syllogism was introduced by a famous philosopher Aristotle.

Terms :-
  1. Major Term :- This is the Predicate of the conclusion.
  2. Middle Term :- This is the word common in both the premises.
  3. Minor Term :- This the subject of conclusion.
Major and Minor Premise :-
Of the two premises, the major premise is that in which the middle term is the subject and the minor premise is that in which the middle term is the predicate.