A problem facing all students who come to study a social science for the first time is that they must do two things simultaneously. They must familiarise themselves with the substance or content of their new subject and, at the same time, they must learn the methodology of the subject. That is, they must become familiar not only with the knowledge and research findings which fill the textbooks but also with the methods by which the knowledge is obtained and organised, that is with the logical basis of the subject itself. The two elements are not separate; they are very closely replaced.
Because we are all familiar with social life through our everyday experiences we may feel that the social sciences are very largely a matter of common-sense. But, as a look at any textbook will quickly indicate, though each of the social sciences is concerned with people in society, each discipline goes beyond common-sense understanding. Each discipline focuses on a particular aspect of social life, each uses particular methods of study and each employs its own set of concepts. It is this set of concepts, the most basic ideas in a subject, which constitutes the 'logical basis of the subject', which enables the social scientist to go beyond everyday common-sense and which distinguishes one discipline from another.