A young activist and highly-educated Cambridge Union debater, Mill would become in time the highest-ranked English thinker of the nineteenth century, the author of the landmark essay On Liberty and one of the most passionate reformers and advocates of his revolutionary, opinionated age. As a journalist he fired off a weekly article on Irish land reform as the people of that nation starved, as an MP he introduced the first vote on women's suffrage, fought to preserve free-speech and opposed slavery, and, in his private life, pursued for two decades a love affair with another man's wife.

To understand Mill and his contribution, Richard Reeves explores his life and work in tandem. His book is a riveting and authoritative biography of a man raised to promote happiness, whose life was spent in the pursuit of truth and liberty for all.