Non-religion

Irreligion (adjective form: non-religious or irreligious) is the absence, indifference, rejection of, or hostility towards religion.

Irreligion may include some forms of theism, depending on the religious context it is defined against; for example, in 18th-century Europe, the epitome of irreligion was deism.

According to the Pew Research Center's 2012 global study of 230 countries and territories, only 16% of the world's population is not affiliated with a religion, while 84% are affiliated. According to their projections, the non-religious, though temporarily increasing, will ultimately decline significantly by 2050 because of lower reproductive rates and ageing.

In 1993, the UN's human rights committee declared that article 18 of the International Covenant on Civil and Political Rights "protects theistic, non-theistic and atheistic beliefs, as well as the right not to profess any religion or belief." The committee further stated that "the freedom to have or to adopt a religion or belief necessarily entails the freedom to choose a religion or belief, including the right to replace one's current religion or belief with another or to adopt atheistic views." Signatories to the convention are barred from "the use of threat of physical force or penal sanctions to compel believers or non-believers" to recant their beliefs or convert.

Most Western democracies protect the freedom of religion, and it is largely implied in respective legal systems that those who do not believe or observe any religion are allowed freedom of thought.

A noted exception to ambiguity, explicitly allowing non-religion, is Article 36 of the Constitution of the People's Republic of China (as authored in 1982), which states that "No state organ, public organization or individual may compel citizens to believe in, or not to believe in, any religion; nor may they discriminate against citizens who believe in, or do not believe in, any religion." Article 46 of China’s 1978 Constitution was even more explicit, stating that "Citizens enjoy freedom to believe in religion and freedom not to believe in religion and to propagate atheism."

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