Oliver Wendell Holmes Jr. said this quote
“ Certitude leads to violence. This is a proposition that has an easy application and a difficult one. The easy application is to ideoologues, dogmatists, and bullies--people who think that their rigtness justifies them in imposing on anyone who does not happen to suscribe to their particular ideology, dogma or notion of turf. If the conviction of rightness is powerful enough, resistance to it will be met, sooner or later by force. There are people like this in every sphere of life, and it is natural to feel that the world would be a better place without them! ”