John Stuart Mill (1806 - 1873) was an English philosopher political economist feminist and civil servant. One of the most influential thinkers in the history of liberalism he contributed widely to social theory political theory and political economy. Mill's conception of liberty justified the freedom of the individual in opposition to unlimited state control. He was a proponent of utilitarianism and contributed significantly to the theory of the scientific method. He was a member of the Liberal Party and the first MP to call for women's suffrage.