I believe a society is best maintained by people who are consonant with its foundational ideas and values, and therefore people's ways of thinking need to evolve in lockstep with society itself...
I agree, and therefore I mostly identify as an incrementalist. However, for society to budge at all, I also believe the rhetoric needs to be honest, and therefore radical. And looking at history we see that power is never given away voluntarily, so the journey to the left has always been punctuated by direct action, protest, and, unfortunately, violence. I can only hope we can collectively find a better way...