Freedom of thought

For instance, the United States Bill of Rights contains the famous guarantee in the First Amendment that laws may not be made that interfere with religion "or prohibiting the free exercise thereof".

[7] In European tradition, aside from the decree of religious toleration by Constantine I at Milan in 313, the philosophers Themistius, Michel de Montaigne, Baruch Spinoza, John Locke, Voltaire, Alexandre Vinet, and John Stuart Mill and the theologians Roger Williams and Samuel Rutherford have been considered major proponents of the idea of freedom of conscience (or "soul liberty" in the words of Williams).

[9] During her reign, however, a number of books published by theorist Giordano Bruno spurred controversy, mentioning topics banned by the Catholic Church such as the possibility of an infinite universe.

Unwilling to recant these ideas, Bruno was eventually burned as a heretic in Rome by the Italian Inquisition, in turn becoming a martyr for free thought.

[10] Oliver Cromwell is described by Ignaz von Döllinger as "the first among the mighty men of the world to set up one special religious principle, and to enforce it so far as in him lay: ...

Examples of effective campaigns against freedom of expression are the Soviet suppression of genetics research in favor of a theory known as Lysenkoism, the book-burning campaigns of Nazi Germany, the radical anti-intellectualism enforced in Cambodia under Pol Pot and in Nazi Germany under Adolf Hitler, the strict limits on freedom of expression imposed by the Communist governments of the People's Republic of China and Cuba or by Capitalist dictatorships such as those of Augusto Pinochet in Chile and Francisco Franco in Spain.