"An enquiry into the nature and cause of the wealth of Nations" is authored by :

Adam Smith

Adam Smith is regarded as the founding father of modern economics (it was known as political economy at that time). He was a Scotsman and a professor at the University of Glasgow. Philosopher by training, his well known work "An Enquiry into the Nature and Cause of the Wealth of Nations" (1776) is regarded as the first major comprehensive book on the subject.