Ai Weiwei is the most famous Chinese artist living today. As an activist, he calls attention to human rights violations on an epic scale; as an artist, he expands the definition of art to include new forms of social engagement. In a country where free speech is not recognized as a right, the police have beaten him up, kept him under house arrest, bulldozed his newly-built studio and subjected him to surveillance. He is viewed as a threat to "harmonious society." The West did not invent revolutionaries. China has an illustrious history of dissidents, anti-authoritarian originals and eccentrics, from the drunken monks of pre-history to counter-culture artists living in today's Beijing. Ai himself is from this long line of free-thinkers and writers, marginalized both by the right and left. From smashing an ancient vase to reciting the names of children who died due to government negligence, Ai's dramatic actions highlight the widening gap between the ideal and the real in Chinese society. He is also one of the earliest conceptual artists to use social media - Instagram and Twitter, in particular - as one of his primary media.