I have never known much good done by those who affected to trade for the Public good.
A. public.
B. good.
Explanation:
Adam smith in the famous passage from the Wealth of Nations says that the butcher who is just following his interest and doing his work sets a goods example to the society and promotes it more effectively without intentionally focusing on it.
He is just doing his work. The author never knew that so much good can be done by those who while serving the society or doing something for public good can do.