Atheism is not a single position
In everyday English, an atheist is often described as someone who believes that no deity exists. In broader philosophical and contemporary usage, atheism can also mean the absence of belief in any deity, without requiring a confident claim that no deity exists.
The word therefore tells us something about a person’s position regarding deities, but it does not by itself describe their ethics, politics, personality, community life or view of science. Atheists may hold many different positions on those subjects.
Why definitions vary
Terms connected with religion often develop different meanings in everyday speech, academic writing and within communities themselves. A definition that is useful in one discussion may be too narrow in another. For that reason, careful writing should state which meaning is intended rather than assume that every atheist uses the word in the same way.
The same principle applies to related terms such as “theist,” “agnostic,” “religion” and “worldview.” People may use these labels differently, and some prefer not to use a label at all.
Word history
Atheism comes through English from Greek roots: a-, meaning “without” or “not,” and theos, meaning “deity.” The basic linguistic sense is therefore connected with being without a belief in a deity. Etymology can illuminate a word’s history, but it does not settle every modern definition.
A spectrum of positions
People’s views about deities can be described in several ways. The categories below overlap in ordinary use, and they should not be treated as a complete map of every person’s outlook.
Theism
Belief in one or more deities.
Strong atheism
The considered view that no deity exists.
Weak atheism
No belief in a deity, without necessarily claiming certainty.
Agnosticism
A view that knowledge of whether a deity exists is unavailable, uncertain or unresolved.
Indifference
Little practical concern about whether deities exist.
Methodological atheism
Studying a subject without assuming a deity in the method of inquiry.
Atheism and religion
Some atheists reject describing atheism as a religion because it lacks belief in a deity, while others use “religion” broadly for systems of meaning, practice or community. This is a disagreement about the definition of religion, not a reason to assign a single identity to all atheists.
Atheists may develop moral commitments, philosophies of life, ceremonies and communities. Those features can be studied without assuming that atheism itself has one universal structure.
Reading with precision
When discussing atheism, ask what the writer means: absence of belief, denial of deities, uncertainty, or a wider non-theistic worldview. Clarifying the definition usually prevents unnecessary disagreement.
Related reading
For comparison, see agnosticism, humanism, basic information about religion and the glossary. The guide to confusing terms discusses why familiar religious words can carry different meanings.