Is this true? In her new book, written with the happiness correspondent of a top US magazine, Oprah Winfrey argues that suffering and effort are vital parts of an enjoyable life.
To be happy you have to be unhappy says Oprah
Talk about it: American talk show host Oprah Winfrey is one of the most influential women in the world. Glossary
Harvard University - One of the oldest and most prestigious universities in the USA.
Thomas Aquinas - One of the most important medieval thinkers. The Italian priest called Aristotle "the Philosopher" and worked to unite pagan Greek philosophy with Christian principles.