 In his spare time he also enjoyed reading about natural sciences and popular novels, such as "Don Quixote" and "Robinson Crusoe".His father's work, "The History of British India" was published in 1818; immediately thereafter, at about the age of twelve, Mill began a thorough study of the scholastic logic, at the same time reading Aristotle's logical treatises in the original language.In the following year he was introduced to political economy and studied Adam Smith and David Ricardo with his father, ultimately completing their classical economic view of factors of production.