[T]he peculiar evil of silencing the expression of an opinion is, that it is robbing the human race . . . those who dissent from the opinion, still more than those who hold it. If the opinion is right, they are deprivedvof the opportunity of exchanging error for truth: if wrong, they lose, what is almost as great a benefit, the clearer perception and livelier impression of truth, produced by its collision with error. John Stuart Mill
1869