 Mill's "comptes rendus" of his daily economy lessons helped his father in writing "Elements of Political Economy" in 1821, a textbook to promote the ideas of Ricardian economics; however, the book lacked popular support.Ricardo, who was a close friend of his father, used to invite the young Mill to his house for a walk in order to talk about political economy.At the age of fourteen, Mill stayed a year in France with the family of Sir Samuel Bentham, brother of Jeremy Bentham.