"In 'Free Speech', Jacob Mchangama traces the long, contested history of a powerful idea, beginning with its origins in the intellectual ferment of classical Athens, where it enabled the development of the world's first democracy. Through captivating stories of defenders of free speech throughout history, from the eighth century 'Abbasid caliph Abu Ja'far al-Mansur to the anti-lynching crusader Ida B. Wells, Mchangama reveals how the free exchange of knowledge and ideas underlies all scientific and literary achievement, and how it has enabled the advancement of civil rights across the globe. Indeed, he argues, freedom of speech has far more often served the cause of the oppressed than the cause of the oppressors. Yet the temptation to restrict speech, too, is a historical constant, and Mchangama explores how elite entrenchment and anxiety about new technologies can lead even the most dedicated defenders of liberty down this dangerous path. Meticulously researched and deeply humane, Free Speech demonstrates just how much humanity has gained from this essential principle - and just how much we stand to lose if we allow it to erode." (Publisher description)