What is atheism? Atheism is:
- The lack of belief in a god or gods or supernatural beings and
- The belief that a god or gods or supernatural beings do not exist.
The “lack of belief” in a god or gods or the supernatural is a (theoretically) neutral position that is narrowly balanced between the belief in a god and the belief that god does not exist. It is the most fundamental definition of atheism and the one that people sometimes take in an effort to avoid an argument about the nature of god.
But as a practical matter – people rarely lack an opinion about the nature of god. Atheists ultimately conclude that a god or gods or supernatural beings do not exist. This is because it is not possible to walk through the world for any period of time and not form an opinion based on the evidence at hand.
If one sees the evidence and starts believing in a god, they are no longer an atheist. They are a theist. If they see the evidence and come to the conclusion there are no gods – they are atheists (with an opinion).