Atheism

Atheism is the denial of the existence of God.[1]

Atheism, as an explicit position, can be either the affirmation of the nonexistence of gods, or the rejection of theism. It is also defined more broadly as synonymous with any form of nontheism, including the simple absence of belief in deities.

Many self-described atheists are skeptical of all supernatural beings and cite a lack of empirical evidence for the existence of deities. Others argue for atheism on philosophical, social or historical grounds. Although many self-described atheists tend toward secular philosophies such as humanism and naturalism, there is no one ideology or set of behaviors to which all atheists adhere; and some religions, such as Jainism and Theravada Buddhism, do not require belief in a personal god.[2]

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[1] Stanford Encyclopedia of Philosophy and the Routledge Encyclopedia of Philosophy,
[2] Wikipedia