The "art of words" has certainly effected huge social change. This is self-evident if you include political commentary and philosophy (Common Sense, Wealth of N

The "art of words" has certainly effected huge social change. This is self-evident if you include political commentary and philosophy (Common Sense, Wealth of Nations, Federalist Papers, Communist Manifesto, etc.). If you restrict it to fiction, a common example is 1906 novel The Jungle by Upton Sinclair. If you're talking about art like paintings, plays, music, etc., I don't have any examples off the top of my head. However, I think it's a truism that art is often the first/only safe place to criticize the powerful. I don't know if that's really art effecting change as much as art giving a voice to underlying forces for change.