[spyrosg]

I'll keep amalgamating viewpoints and ideas, as I don't see the usefulness of the distinction so far.

As you say, for the renaissance, the change in viewpoints were caused by the conditions of the time. The power of social change ultimately lies in big changes in the physical world, not in civilised humans and their thinking and arguing.

As I mentioned, that last idea seems to me to be just a covert way to pretend we have any control, when we are actually rather effete and incapable of shaping the world into what we'd like.

You mentioned the western revolutionary sentiment of the sixties in another answer. If you believe Strauss and Howe (http://www.fourthturning.com/), they didn't have a choice. That generation believed whatever humans believe when they are put into the conditions they were in, repeating a pattern with little self-consciousness.

edit: the power of change -> the power of social change