Man is inquisitive. He wants to understand the world around him. Man’s reflection on life, nature and society has resulted in formation of ideas.
This rational endeavour has indeed helped for the growth of knowledge. This process is going on from the early phase of human civilization to our age of technological sophistication.
The knowledge that man acquires in an age is handed down to the posterity. That becomes possible because man is capable to communicate through language.
That is why what were composed thousands years back are even available to us now and we are able to read and understand the mind of the people living in that remote past.
Thus man’s rational capacity and the ability to speak language have helped him to develop knowledge on very many fields.
Man is bestowed with sense organs- and the intellectual capacity to comprehend the environment around him. By sense experience man learns many things about the physical world. By perceiving things, events and processes and mentally comprehending them he develops systematic body of knowledge which is called science.
Science is a systematic body of classified empirical knowledge. Physics, chemistry, astronomy etc. are different branches of natural science. As nature is vast and unlimited there are different specializations in the field of natural science.
Each branch of natural science studies and explores some invariant laws that operate in a particular area of nature. Physics, for example, explores the fundamental relationships between matter and energy, chemistry is concerned with the composition of substances and their reactions with one another, astronomy studies nature, position and motion of heavenly bodies, so on and so forth Of course there many areas of natural science which are complementary to each other.
There is no watertight compartment between different areas of natural science, rather they collectively ma system.
Man, too, we know, is a social being. Human society has passed through various evolutionary changes. It has become stable in the long process of historical development. Man has also become interested to study his society in a systematic way.
Consequent upon this study there are different branches of social science. Economics, political science, sociology etc. are branches of social science trying to interpret and explain the differed social aspects of human life and behaviour. As there are different areas of social interaction social sciences study those making mutual specializations.
Natural science and social science constitute the realm of physical science. Unlike physical science there is another branch of knowledge, which covers different areas of mathematics. Mathematics is a formal science in which theorems are necessarily brought out from the axioms, which are considered as self-evident.
The relation between an axiom and its theorem or theorems is only implication or necessitation at an abstract level. That is the structural character of formal science, says mathematics, is that of axiomatic deductive. Algebra, geometry, calculus etc. are some of the major branches of mathematics.
All these areas of knowledge- physical science and formal science- are founded on some methodological device. In each sphere of science some process of reasoning is applied to obtain accurate knowledge.
Our knowledge in these spheres- whether obtained directly indirectly or inferentially- assumes some process of reasoning. That is, any systematic or methodological knowledge is bound to adopt some definite procedure and employ some reasoning.
The process, procedure or reasoning applied in a system of study ordinarily does not come within that system to be investigated. There is another area to consider and examine the different procedures or reasoning that is applied to have specialized knowledge of science.
A physical scientist applies some reasoning, methodology and procedure to build up his system or reach some generalizations. But he is not theoretically concerned with the methodology that he applies. This can be explained by an analogical example.
A common man communicates his ideas or feelings through the language he has learnt. He makes intelligible communication by following the conventional rules of a language that he has learnt. A lay man or even an illiterate person finds no difficulty to make intelligible communication by following certain rules of grammar. For any intelligible linguistic communication presupposes some rules of grammar.
A linguist or grammarian, on the other hand, studies the rules of grammar of a language at a theoretical plane which a common man presupposes or applies in practice without being theoretically conscious of them. Somebody may be using some rules without being conscious of them but they can be explained at a theoretical level.
Similarly the methodology or procedure that is used in different areas of science is not analytically elucidated by the scientist. He has a practical understanding or implicit mastery of the procedure that is necessary for his system of knowledge to be formulated. But such procedures and the process of reasoning are analyzed and explained theoretically by a logician.
A logician is not interested in making empirical generalization nor does he investigate the cause of a phenomenon. Such enterprise is carried out by a scientist dealing with empirical phenomena. But a logician on the other hand investigates the valid forms of reasoning and the theoretical procedure underlying any valid generalization.
While exploring the valid forms of reasoning at theoretical plane logic also studies the auxiliary processes connected with reasoning. Logic, therefore, can be taken as a reflective enquiry or in philosophical terms a second order activity. Its procedure is analytical or conceptual but not empirical.
Not only in intellectual pursuit but even in practical life we draw conclusion and usually make inference. Drawing conclusion, making inference, formulating arguments etc. are normal rational activities of a person.
In the morning after getting up if one finds the ground is wet. he infers rain at night. On the road if I see a crowd and a vehicle lying 1 imagine an accident. After seeing two bodies with some facial resemblance I assume that they are brothers.
In such numerous occasions we very often make inference in practical life. But whether an inference is sound, appropriate or not requires understanding of the rules of valid reasoning.
Thus, logic is primarily concerned with the valid forms of reasoning. It lays bare the fundamental principles underlying the valid forms of arguments. In any branch of knowledge or even in the practical commerce of life we make inference and present argument.
We draw conclusion on the basis of some evidence. When a conclusion is drawn form some evidence there is an inference. An inference is a mental process and its manifestation in language is called an argument.
In other words when an inference is expressed in language it is called argument. Logic as a system of study deals primarily with criteria for the evaluation of arguments with a view to determining the conditions of their validity.
Classical logic centres round two areas such as Deductive Logic and Inductive Logic. Deductive logic received a systematic elaboration in Aristotle (384-322 BC). Inductive logic on the other hand had a late theoretical emergence.
Although there were some scattered ideas about induction in the writings of some ancient and medieval writers, Francis Bacon (1561-1626) gave a systematic presentation of inductive logic. After Bacon there are a number of great thinkers who have made significant contribution to inductive logic.
Before going to discuss the nature, problem and procedure of induction, a brief discussion on deductive logic i.e. the nature of deduction will throw insight to understand the perspectives of induction and the nature of logic as well.