From GK Chesterton's essay 'The Anarchist'.
Chesterton was a beautiful prose stylist, and The Man Who Was Thursday is still one of my favourite books ever. Nevertheless, I sympathized with Lucian Gregory more than Gabriel Syme; and I feel that Chesterton's image of the dapper, theory-obsessed anarchist is less effective than it might be. It's possible to ridicule any political philosophy - indeed, any philosophy - by setting as its sole defender a man like Chesterton's Anarchist, a man who can speak for hours without mentioning anything of real-world significance.
If Chesterton had met his other anarchist, Gregory, on that park bench, I suspect he would have had a harder job dismissing him. And regardless, I like to think that today you could reply to Chesterton's question by mentioning Occupy or Tahrir Square (and I'm sure there were equivalents in Chesterton's time.) An army of revolt is not only possible without discipline, it is impossible with discipline. A revolution organized by a central authority is a revolution in the literal sense of the word - it goes around and around, without changing anything.