Atheism Defined

The word atheism comes from the Greek atheos (ἄθεος), meaning “no god.” It combines the prefix a– (“no”) and theos (“god”), with the suffix -ism indicating a belief or doctrine. In its most literal sense, atheism means “the belief that there is no God or gods.”

The Stanford Encyclopedia of Philosophy explains it this way: “The term ‘atheism’ is standardly used to refer to the proposition that God does not exist (or, more broadly, to the proposition that there are no gods).”

Atheism, then, is not merely “a lack of belief,” but a definite position — a belief that rejects the existence of any divine or supernatural being. Where theism affirms the existence of God, atheism denies it; where agnosticism suspends judgment, atheism makes a clear claim.

Over time, some have attempted to redefine atheism as simply “a lack of belief in gods.” But traditionally, philosophically, and linguistically, atheism has always meant the belief that there is no God. The distinction matters: a lack of belief (agnosticism or non‑theism) is not the same as belief in nonexistence (atheism).

Put simply:

– Theism affirms that God exists.
– Atheism asserts that God does not exist.
– Agnosticism withholds judgment, admitting uncertainty.

These are the only three logical attitudes one can take toward the claim “God exists.” Atheism does not merely reject this claim; it advances a counterclaim — that there is no God.

And because it is a claim, it carries the burden of proof. The assertion that there is no God must therefore be supported by evidence or sound reasoning.

Agnosticism, on the other hand, makes no such claim. It neither affirms nor denies the existence of God, but simply admits, “I do not know.” For that reason, agnosticism requires no evidence — it is a position of suspended judgment rather than declaration.