Science is a systematic body of classified knowledge. While a branch of natural science explores the invariable laws that operate in a particular area of nature a branch of social science studies human behavior and social interaction in some sphere of society.
Natural science and social science constitute the physical science as different from formal science.
But each branch of science applies some method, procedure and process of reasoning to reach its conclusions. These are not studied by science but analysed at a different sphere.
Logic primarily examines the valid forms of reasoning and the procedure underlying any valid generalization. It deals with the criteria for the evaluation of arguments.
Classical logic centres around two areas such as Deductive Logic and Inductive Logic. Deduction and induction.
In a valid deductive argument the conclusion necessarily follows from the premises. There is a relation of implication between the premise and the conclusion. In deductive reasoning the thrust in on formal consistency. Deductive logic explores the forms of valid reasoning.
Inductive logic examines the conditions for appropriate generalization. Science makes generalization on the basis of observation of exception less regularities of nature.
Inductive generalization involves a leap. So a generalization is only probable. Probability admits of degrees.
The deductive procedure is applied in mathematics but the inductive method is applied in physical science.
Deduction and induction are two different processes and their sphere of application is also different.
Some incorrect or misleading views with regard to the relationship between deduction and induction are-
a) Deduction is prior to induction or induction is prior to deduction.
b) One is fundamental than the other.
c) Deduction is a descending process and induction is an ascending process.
d) Induction and deduction are essentially similar and their difference is only with regard to their starting point.
PRIMARY INDUCTION AND SECONDARY INDUCTION:
In primary induction a generalization is made on the basis of observation of facts. In secondary induction theories are formulated having greater explanatory power. The generalization in primary induction has empirical instantiation but the generalization in secondary induction is a non-instantial hypothesis.
PROCEDURE OF INDUCTION:
The procedure of induction is the basis of scientific knowledge. The procedure of induction passes through the different stages like-
a) Observation of facts including definition, analysis and elimination by varying the circumstances;
b) Formation of hypothesis to explain a phenomenon;
d) Verification by appealing to facts;
e) The generalization must be coherent with a system.
PROBLEM OF INDUCTION:
A generalization is like a universal phenomenon of nature covering unlimited cases. It ranges over unobserved and unlimited number of instances. The problem of induction is how to bridge the leap between the observed and limited cases to the unobserved and j unlimited cases.
Aristotle justifies induction by deductive procedure and Mill solves the problem of induction by appealing to the law of uniformity of nature and the law of causation.