Unbelievers believe that God un-exists
"un-exists" is an odd term to use here. "Unbelievers believe that God does not exist" would be more sensible.
There's little to be gained by labelling people one way or the other.
Which I think is the most salient point here! We want things to fit into neat, tidy categories but they rarely do (particularily when it comes to beliefs and other parts of the human experience.
HBD
Whoever calls me ignorant shares my own opinion. Sorrowfully and tacitly I recognize my ignorance, when I consider how much I lack of what my mind in its craving for knowledge is sighing for... I console myself with the consideration that this belongs to our common nature. - Francesco Petrarca
"Nothing is easier than to persuade people who want to be persuaded and already believe." - another Petrarca gem.
Ignorance is a most formidable opponent rivaled only by arrogance; but when the two join forces, one is all but invincible.
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