The labor movement had been pretty much killed in the 1920s, almost destroyed. It revived in the 1930s and made a huge difference. By the late 1930s the business world was already trying to find ways to beat it back.

Some of the most moving experiences I've had are just in black churches in the South, during the Civil Rights Movement, where people were getting beaten, killed, really struggling for the most elementary rights.

We should therefore be opposed to institutional barriers to that freedom: Military dictatorships, for example. Or states run by a Central Committee.

We could not bring democracy to South Vietnam at a cost that we were willing to accept. So it was a disaster. That' is the left extreme.

Some of the younger people afford hope for the future. I am not opposed to reform initiatives. For example, if you can build up enough popular support in the United States to put through a reasonable health care program or to support the rights of the working people against the version of NAFTA which was rammed through, these can be good things.

If you go to one demonstration and then go home, that's something, but the people in power can live with that. What they can't live with is sustained pressure that keeps building, organisations that keep doing things, people that keep learning lessons from the last time and doing it better the next time.

Physics and those parts of other fields that grow out of physics - chemistry, the structure of big molecules - in those domains, there is a lot of progress. In many other domains, there is very little progress in developing real scientific understanding.