Implicit and explicit atheism

Some varieties of atheism

	on left	Implicit "negative" / "weak" / "soft" atheists who lack a belief in gods without explicitly denying the concept, includes very young children, those who are unacquainted with the concept or are truly undecided.
	on right	Explicit "negative" / "weak" / "soft" atheists who do not believe that gods exist necessarily.
	on right	Explicit "positive" / "strong" / "hard" atheists who firmly believe that gods do not exist.

Note: Areas in the diagram are not meant to indicate relative numbers of people.

Implicit atheism and explicit atheism are types of atheism. In George H. Smith's Atheism: The Case Against God, "implicit atheism" is defined as "the absence of theistic belief without a conscious rejection of it", while "explicit atheism" is "the absence of theistic belief due to a conscious rejection of it". Explicit atheists have considered the idea of deities and have rejected belief that any exist. Implicit atheists, though they do not themselves maintain a belief in a god or gods, have not rejected the notion or have not considered it further.