The duty and the right to express one's opinion freely may be meaningless—and on occasion even injurious to the best interests of the society—if those opinions are not based on sound thought, which, in its turn, presupposes the possession of sound knowledge.

we should not assume that experts are the only ones who have a right to express themselves on questions affecting the organization of society.

People can tell you to keep your mouth shut, but that doesn't stop you from having your own opinion.

...[S]ome of the opinions which people entertain should be respected, and others should not.

Everyone is entitled to his own opinion, but not his own facts.

Remember that everyone has opinions and they are often bad. Opinions are easy to produce; everyone has plenty of them and most people are eager to share them — even to fight for them. Unfortunately many are worthless or even harmful, including a lot of your own.

Opinions need a willing ear.

In my ugly, elitist opinion we are not all entitled to voice our opinions, we are entitled to pass along our informed opinions.

Remember that all is opinion.

Nowadays public opinion is not the sum of private opinions. On the contrary, private opinions are an echo of public opinion.

The opinion which other people have of you is their problem, not yours.

"Everyone, they say, is entitled to his opinion".

If there are any persons who contest a received opinion, or who will do so if law or opinion will let them, let us thank them for it, open our minds to listen to them, and rejoice that there is some one to do for us what we otherwise ought, if we have any regard for either the certainty or the vitality of our convictions, to do with much greater labour for ourselves.

But every difference of opinion is not a difference of principle.