Freedom of thought

Freedom of thought (also called the freedom of conscience or ideas) is the freedom of an individual to hold or consider a fact, viewpoint, or thought, independent of others' viewpoints. It is different from and not to be confused with the concept of freedom of speech or expression.

Freedom of thought is the precursor and progenitor of—and thus is closely linked to—other liberties, including freedom of religion, freedom of speech, and freedom of expression. Though freedom of thought is axiomatic for many other freedoms they are in no way required for it to operate and exist. Conception of a freedom or a right does not guarantee its inclusion, legality, or protection via a philosophical caveat. It is a very important concept in the western world and nearly all democratic constitutions protect these freedoms. For instance, the 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". U.S. Supreme Court Justice Benjamin Cardozo reasoned in Palko v. Connecticut (1937):

Freedom of thought... is the matrix, the indispensable condition, of nearly every other form of freedom. With rare aberrations a pervasive recognition of this truth can be traced in our history, political and legal.

Such ideas are also a vital part of international human rights law. In the Universal Declaration of Human Rights (UDHR), which is legally binding on member states of the International Covenant on Civil and Political Rights (ICCPR), freedom of thought is listed under Article 18:

Everyone has the right to freedom of thought, conscience and religion; this right includes freedom to change his religion or belief, and freedom, either alone or in community with others and in public or private, to manifest his religion or belief in teaching, practice, worship and observance.

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