Atheism

Atheism is, in the broadest sense, the absence of belief in the existence of deities. Less broadly, atheism is the rejection of belief that any deities exist. In an even narrower sense, atheism is specifically the position that there are no deities. Atheism is contrasted with theism, which, in its most general form, is the belief that at least one deity exists.

The etymological root for the word atheism originated from the Greek (atheos), meaning "without god(s)". In antiquity it had multiple uses such as a pejorative term applied to those thought to reject the gods worshiped by the larger society., it could refer to someone who was was forsaken by the gods or someone who had no commitment to the gods. However, the actual term atheism emerged first in the 16th century. With the spread of freethought, skeptical inquiry, and subsequent increase in criticism of religion, application of the term narrowed in scope. The first individuals to identify themselves using the word atheist lived in the 18th century during the Age of Enlightenment. The French Revolution, noted for its "unprecedented atheism," witnessed the first major political movement in history to advocate for the supremacy of human reason.

Arguments for atheism range from the philosophical to social and historical approaches. Rationales for not believing in deities include arguments that there is a lack of empirical evidence, the problem of evil; the argument from inconsistent revelations, the rejection of concepts that cannot be falsified, and the argument from nonbelief. Although some atheists have adopted secular philosophies (eg. secular humanism), there is no one ideology or set of behaviors to which all atheists adhere. Many atheists hold that atheism is a more parsimonious worldview than theism and therefore that the burden of proof lies not on the atheist to disprove the existence of God but on the theist to provide a rationale for theism.

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