Few philosophers have had a greater impact on the modern world than John Stuart Mill. World leaders, political parties and academics have all taken inspiration from his pioneering concepts. In On Liberty, Mill wrote a classic defence of liberalism, human rights and utilitarianism. Applying his theories to politics, On Liberty is a magnificent examination the nature of state and society. First published in 1859, Mill's libertarian ideas continue to exert an incredible influence on politics and philosophy today.