Adam Smith represents classical, Alfred Marshal represents the neo-classical school of thoughts and the moderns are represented by Lionel Robbins.
Adam smith (1723-1790) who is known as a father of economics, in his work "An enquiry into the causes and nature of wealth of nations" defined economics first time in 1776. He, defining economics said that:
The above mentioned book of Smith has been divided into four parts; Consumption, production, exchange and distribution of wealth. He came up with an opinion that the wealth, goods and services are produced in every country in accordance with the laws. Concerning the exchange and with regard to distribution of wealth, he developed some laws for mutual exchange and with regard to distribution of wealth. The concept of wealth given by Smith was misinterpreted as well as misunderstood therefore, Ruskin and Carlyle, the renowned social reformers of their own time, declared economics a dismal (negative) branch of knowledge. They said that Smith's definition motivates the people for "wealth worship and make them selfish". Wealth is the mean to reach the end not the end in itself. ...Show more