At present, due to continuous change in the economic activities of human life, and due to the contradictory definitions of economics, many disagreements are found in the economists regarding the nature and extent of economics. 

Prof Keynes has included three elements in the scope of economics.

1. Subject matter of economics 

2. Nature or characterstics of economics 

3. Relationship between economics and other sciences

The subject matter of economics is divided into five parts : 

1. Consumption 

2. Production 

3. Exchange 

4. Distribution 

5. Public finance.

Nature or Behaviour of Economics : The following issues are included in the study of nature/behaviour of economics.

i. Nature of Economics as a Science : Science is such a systematic and complete study of knowledge which interprets the relationship between cause and effect. Science performs substantial analysis of an incident, studies it systematically and on that basis, it forecasts and makes prediction regarding any fact. Likewise, economics uses a scientific procedure to understand the relation between the causes and consequences of economic activities and for the formation of economics principles and regulations. It also has the capability of interpreting economics events in a correct and appropriate way and also has the power to make predictions. Therefore economics is science due to all these features.

ii. Nature of Economics as normative or positive : In the form of positive science, economics tells about the relationship between causes and consequences. It interprets that-What is this ? Why is it so? How does it happen? It cannot tell anything about the merits or demerits, correctness or defects of economic activities. This is based on discretion or on prudence.

While as a Normative science it analyzes the facts associated with policies, i.e. what ought to be done? What should be done in a particular condition? In the form of normative science, economics throws light on the merits and demerits of economic activities and actions.

iii. Economics as an art : Achieving an objective with skill is art. Art provides us practical knowledge. It not only analyzes the problem, but also provides solutions, and only an economist can take decision on the problems which are purely of economic nature. Major objective of economics is to maximize the welfare of an individual or the society. Policies which are adopted by the government or an economist to achieve a fixed objective will be considered as an art.

If economics is studied in the form of art, then this will facilitate the examination of economic principles and it will also be helpful in finding out whether the principle is correct or not, by which it becomes possible to implement that principle.

iv. Both Science and Art : Economics is a science as well as an art. In the form of science, economics is not only a positive science, but a also is normative science. Economics performs a study of both theoretical as well as practical aspects of a topic. Theoretical aspect is associated with science and practical aspect is associated with art. Theoretical economics is a science and practical economics is an art.