It's a dark January evening, and in an anonymous townhouse near Paddington station, a man is talking about how to stage a revolution.

A young Iranian asks a question: "The youth in Iran are very disillusioned by the brutality of the violence used against them ... It has stopped all the street protest," she says. "What would you say to them? How can they get themselves organized again?"

The man thinks for a moment. He's an unlikely looking radical -- slightly stooped with white hair, his bent frame engulfed by the low chair he's sitting in.

When he opens his mouth to speak, all eyes in the room are fastened on him.

"You don't march down the street towards soldiers with machine guns. ... That's not a wise thing to do.

"But there are other things that are much more extreme. ... You could have everybody stay at home.

"Total silence of the city," he says lowering his voice to a whisper, punctuating the words with his bent hands, as if he's wiping out the noise himself.

"Everybody at home." The man's eyes scan the room. "Silence," he whispers again.

"You think the regime will notice?"

He looks around the room, nodding almost imperceptibly. On the wall behind his head hangs a huge print of the Hiroshima atomic bomb mushrooming into the sky.

This is political scientist Gene Sharp, and explosive ideas are his specialty.......