I can think that you are mistaken, but I have to be ready to give my life to maintain your right to make mistakes. I have to, though, have the right to say that you're mistaken. This is the principal of the liberal society.
我可以认为你错了，但我必须准备好用我的生命来维护你犯错误的权利。不过，我有权利说你错了。这是自由社会的原则。