John Stuart Mill

 

 

             Strange it is, that men should admit the validity of the arguments for free discussion, but object to their being "pushed to an extreme"; not seeing that unless the reasons are good for an extreme case, they are not good for any case. Strange that they should imagine that they are not assuming infallibility when they acknowledge that there should be free discussion on all subjects which can possibly be doubtful, but think that some particular principle or doctrine should be forbidden to be questioned because it is so certain, that is, because they are certain that it is certain. To call any proposition certain, while there is any one who would deny its certainty if permitted, but who is not permitted, is to assume that we ourselves, and those who agree with us, are the judges of certainty, and judges without hearing the other side.

 

 On Liberty