A.J. Ayer, Theodore Drange, and other philosophers see both atheism and agnosticism as incompatible with ignosticism on the grounds that atheism and agnosticism accept "a deity exists" as a meaningful proposition which can be argued for or against.
Irreligion, which may include atheism, agnosticism, ignosticism, antireligion, skepticism, freethought, antitheism, apatheism, non-belief, secular humanism, and deism, varies in the different countries around the world.