The history of intellectual growth and discovery clearly demonstrates the need for unfettered freedom, the right to think the unthinkable, discuss the unmentionable, and challenge the unchallengeable. To curtail free expression strikes twice at intellectual freedom, for whoever deprives another of the right to state unpopular views necessarily also deprives others of the right to listen to those views.

No generalization is wholly true—not even this one.

Even a dog distinguishes between being stumbled over and being kicked.

I think that we should be eternally vigilant against attempts to check the expression of opinions that we loathe and believe to be fraught with death, unless they so imminently threaten immediate interference with the lawful and pressing purposes of the law that an immediate check is required to save the country.

To be civilized is to be potentially master of all possible ideas, and that means that one has got beyond being shocked, although one preserves one's own moral aesthetic preferences.

I think it not improbable that man, like the grub that prepares a chamber for the winged thing it never has seen but is to be - that man may have cosmic destinies that he does not understand.

It is perfectly easy to be original by violating the laws of decency and the canons of good taste.