From Libertarian Wiki

John Stuart Mill (20 May 1806 – 8 May 1873), English philosopher, political theorist, political economist, civil servant and Member of Parliament, was an influential libertarian thinker of the 19th century whose works on liberty justified freedom of the individual in opposition to unlimited state control. He was an exponent of utilitarianism, an ethical theory developed by Jeremy Bentham, although his conception of it was very different from Bentham's. He clearly set forth the premises of the scientific method.