...isn't theism also a disbelief? A disbelief or lack of belief in the non-existence of God or gods.
It seems like the 'lack of belief' part is kind of sloppy, because you could end up calling an agnostic a 'theistic atheist', or an 'atheistic theist', since an agnostic lacks beliefs in both directions.
'Agnostic' seems the better term if you're emphasizing lack of belief.
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