Concepts in Logic

1. INFERENCE

•    It means “to infer” or to draw out or to get a truth or conclusion from something.
•   It is a process by which one proposition is arrived at and affirmed on the basis of          one or more other propositions accepted as the “starting point.”

2. ARGUMENT 

Any group of propositions of which one is claimed to follow from the  others, which are regarded as providing support or ground for the truth.

Examples:    JOHN is intelligent because he got excellent grades.

                  SHE is beautiful because she has long and shiny hair.

                  SHE is pretty because she is sexy.

3. SYLLOGISM

An instance of a form of reasoning in which a conclusion is drawn (whether validly   or not) from two given or assumed propositions (premises), each of which shares a term with the conclusion, and shares a common or middle term not present in the conclusion.

It is also known as "deductive reasoning".

          Example:       All men are rational.

                              John is a man.

                              Therefore, John is rational.

Logic

Logic (from the Greek λογική logikē)

·      It is the formal systematic study of the principles of valid inference and correct reasoning.

·         Logic is used in most intellectual activities, but is studied primarily in the disciplines of philosophy, mathematics, semantics, and computer science.

·         It examines general forms which arguments may take, which forms are valid, and which are fallacies.

·         In philosophy, the study of logic is applied in most major areas: ontology, epistemology, ethics, metaphysics.

·         In mathematics, it is the study of valid inferences within some formal language.

·         Logic is also studied in argumentation theory.

·         Logic was established as a discipline by Aristotle, who gave it a fundamental place in philosophy. 

Logic as “ars artium”

• It is the "Art of Art"
• It is regarded as an instrument for arriving at a correct and valid inference. 
• It speaks of principles necessary for arriving at a correct and valid inference. 

Logic as “scientia scientiarium”

    Logic is a science of science, since it presents some principles necessary for the attainment of correct and valid inference in a systematic way.

Importance of Logic

1. The proper study of LOGIC develops in us the habit of clear and critical thinking. 

2. It helps us detect fallacious and illogical thinking. 

3. It trains us in the techniques of determining assumptions and implications.