John Stuart Mill (1806-1873) was a British philosopher with the focus on the political and economical fields. He is now considered one of the 'fathers' of liberalism, defending the conception of individual freedom that faces the unlimited governmental control. Eventually John Mill became a member of the British Parliament. His philosophical works are: 'On Liberty', 'A System Of Logic' and 'Utilitarianism'. 'Utilitarianism' is considered one of the key works of John Stuart Mill as it's titled after his ethic theory of the same name. The Book initially appereared as a series of three articles published in 'Frazer's Magazine' and then reprinted as a single book in 1863. In this work Mill's ideal are revealed through the topics of pain and pleasure, the so-called 'The Greatest Happiness Principle' and others.