The right and freedom to freely express any opinion without censorship or restraint, including the right to receive or impart information through any medium. Freedom of speech promotes inquiry and assists in the emergence of truth. In many societies, it is believed to be of intrinsic value as an element in individual well-being and self-fulfilment. It implies freedom of conscience and religion, freedom of the press, and free participation in political activity; and is indicative of a free society, rather than an authoritarian one.
Freedom of speech is frequently limited on grounds that fall into two categories. Speech is limited on a procedural basis, restricted based on time, place, and manner on the form and forums of its exercise. Speech is limited on a substantive basis involving restrictions on content, such as libel, slander, incitement to riot, pornography, obscenity, and in cases where copyright or national security is threatened, or contempt of court is involved. In free countries, prior restraint is still not involved in limiting such content.
Pragmatic arguments in opposition of limiting freedom of speech include the contentions that speech can offend or annoy but never harm; or that the harms of speech are outweighed by the benefits and by the avoidance of harms that that its suppression would entail.
Freedom of speech is considered one of the basic human rights, included in the Universal Declaration of Human Rights: "Whereas disregard and contempt for human rights have resulted in barbarous acts which have outraged the conscience of mankind, and the advent of a world in which human beings shall enjoy freedom of speech and freedom of belief and freedom from fear and want has been proclaimed as the highest aspiration of the common people"; and in the European Convention on Human Rights: "Everyone has the right to freedom of expression. This right shall include freedom to hold opinions and to receive and impart information and ideas without interference by public authority and regardless of frontiers"; and guaranteed in the first amendment to the U.S. Constitution: "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press, or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances."
See also: censorship
, freedom of the press
, Amendment I
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind. Were an opinion a personal possession of no value except to the owner; if to be obstructed in the enjoyment of it were simply a private injury, it would make some difference whether the injury was inflicted only on a few persons or on many. But the peculiar evil of silencing the expression of an opinion is, that it is robbing the human race; posterity as well as the existing generation; those who dissent from the opinion, still more than those who hold it. If the opinion is right, they are deprived of 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, On Liberty, 1859
"Restriction of free thought and free speech is the most dangerous of all subversions. It is the one un-American act that could most easily defeat us." - U.S. Supreme Court Justice William O. Douglas
"My definition of a free society is a society where it is safe to be unpopular." - Adlai Stevenson, October 7, 1952
"I disapprove of what you say but I will defend to the death your right to say it." - attributed to Voltaire, from S.G. Tallentyre (Evelyn Beatrice Hall), The Friends of Voltaire, 1907
"One of the few remaining freedoms we have is the blank page. No one can prescribe how we should fill it." - James Kelman, The Guardian, October 12, 1994
"One man's vulgarity is another's lyric." - U.S. Supreme Court Justice John M. Harlan, Cohen v. California (1971)