philosophy, cultural-identity, historyPossible Duplicate:
Historically speaking, is there someone that is recognized as the first atheist?
When was the first time the believing in deities emerged as a formulated concept?
The term itself originates (perhaps even re-originates) in the 16th century, though what we would recognize modern 'positive' atheism doesn't properly emerge until the 18th century.
Note that the basic position of not-believing-in-theism is almost certainly as old as the position of theism itself.
(You may wish to look at Wikipedia's article on the history of atheism.)
Sometime back in the primordial soup… It probably took a while for a creature to evolve enough imagination to start ascribing natural phenomena to some kind of supernatural being.
But, if you mean consciously - then probably just as long as theism has been around (“I don’t believe that the Lord Ug causes fire”).
As a concept, it has to go back at least to Biblical times, since Psalm 14:1 says, in part, “The fool hath said in his heart, ‘[there is] no god.’” (KJV translation).
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