We, human beings, are rational animals. As rational beings we seek reasons for our beliefs. It is of course true that we do not always provide reasons for our convictions. But we do recognise the importance of providing reasons or justifications in support of what we claim to be true. The activity of providing reasons for a claim is called reasoning.

This reasoning, as expressed in language, is called argument. In other words, an argument is a piece of reasoning which consists of a claim together with the reasons in support of that claim. An argument is a sequence of sentences, where one of the sentences is the conclusion (or the claim), and the sentences which provide the reasons are the premises.

Note that the sentences expressing reasons are called premises. And the sentence expressing the claim is called the conclusion. Thus, a sequence of premises together with a conclusion is called an argument. Consider the following example:

(1) If logic were difficult then many students would not like logic.


(2) In fact, many students like logic.

(3) Therefore, logic is not difficult.

This is an argument consisting of three sentences of which (1) and (2) are premises and is the conclusion. In this argument (3) expresses the claim “Logic is not difficult” and in support of this claim the two other sentences (1) and (2) are advanced as evidences. The sentences (1) and (2) together provide the justification for accepting the truths expressed are sentence.

Our intellectual or cognitive activity is argumentative in nature. Scientific activities, a paradigm case of intellectual activities, are essentially reason-governed. Arguments are the heart and soul of every science. By the method of rational enquiry science discovers truths, establishes hypothesis and formulates laws.


No genuine scientific activity can afford to neglect arguments in the pursuits of knowledge. Like that of scientific activities, in our everyday life also, we normally seek reasons for our beliefs and actions. When our beliefs and actions are not grounded on proper reasons our life often becomes miserable.

Suppose someone argues that Ashok is hones because he is well-dressed. This is not a good argument, as the evidence cited in favour of the premise does not provide justification of the claim. Being well-dressed is not at all a reason for believing in the honesty of Ashok, because, there are many well-dressed persons who are not honest. Thus, one who trusts Ashok to be honest on such a wrong ground might land himself in trouble.

We have already noticed that an argument is a sequence of sentences of which one sentence is claimed to be true on the basis of the rest of the sentences. We also noted that the sentence whose truth is being claimed is the conclusion and the sentences that provide the justification for the claim are the premises of the argument. Here we are using the word argument in a board sense to include both good and bad arguments, In other words, whenever some claim is made on the basis of some evidence, we call it an argument. If the evidences justify the claim, we call it a good argument, otherwise it is not.

Logic is a study of the methods and principles of correct or good arguments. It teaches us how to construct good arguments and detect mistakes in our arguments.


The knowledge of logic enables us to increase clarity, consistency and cogency of reasoning in our intellectual as well as everyday life. It also helps us to recognise fallacies or errors in our speech and writings.

The knowledge of the principles of good reasoning helps us to avoid logical errors that otherwise would creep into our thoughts causing confusions and puzzles. From this we cannot however claim that a logician or a reasonably good logician cannot commit any logical error.

A logician, as a human being, may commit logical mistake or even argue wrongly. This is quite possible. What we are claiming is that a person with the knowledge of logic is better equipped to avoid errors in. arguments and argue more efficiently than what he or she would have done without knowledge of logic. Logical thinking is a skill that can be acquired by the study of logic.

Logic promotes rational thinking, critical attitude and thereby help us to form a scientific world view. Therefore, it is desirable that one should know the basic principles of good argument. The knowledge of this would place one in a comparatively better position to understand the situation, evaluate beliefs and take correct decisions.


Logic also teaches us to appreciate the good arguments and criticise the bad ones advanced by others. Since logic, in general, deals with arguments, let us continue Mir analysis of the notion of an argument.