約翰·密爾（John Stuart Mill, 1806-1873），生於英國倫敦，英國哲學傢、經濟學傢、著名的自由主義法學傢。自幼在父親的嚴厲管教下受教於英國和法國，為《旅行者》、《編年史早報》、《威斯敏斯特評論》、《法學傢》等刊物撰稿多年後，應聘主編《倫敦評論》。在此期間的著述後被收入《論文集》中（1859）。密爾主要著作有《邏輯方法》（1843）、《政治經濟學原理》（1848）、《婦女屈從》（1869）、《論自由》（1859）、《代議製政府》（1861）等。其中《代議製政府》是西方第一部論述代議製的專著，是密爾政治思想特彆是國傢理論的一部重要著作。約翰.密爾的代議製理論主要包括代議製政府的形式、職能、民主製、選舉權、議會以及地方代錶機關和民族等問題。

Since its first publication in 1859, few works of political philosophy have provoked such continuous controversy as John Stuart Mill's "On Liberty", a passionate argument on behalf of freedom of self-expression. This classic work is now available in this volume which also includes essays by scholars in a range of fields. The text begins with a biographical essay by David Bromwich and an interpretative essay by George Kateb. Then Jean Bethke Elshtain, Owen Fiss, Judge Richard A. Posner and Jeremy Waldron present commentaries on the pertinence of Mill's thinking to early 21st century debates. They discuss, for example, the uses of authority and tradition, the shifting legal boundaries of free speech and free action, the relation of personal liberty to market individualism, and the tension between the right to live as one pleases and the right to criticize anyone's way of life.