Is atheism a belief?

[The Grand Nudger]

At work.

They're all the same example.  

"Which creature" demonstrates an understanding of the category "creatures".  "Which element" the category "elements".   We're asking for clarity or specificity in a list of known and understood x's (and maybe even allowing for ones we're unfamiliar with).   This is an explicit demonstration of coherence. Nothing is more or less coherent than this.

Unless a person believes in at least one of the individual referents (including the possibility of some unknown referent) then the answer to the question of belief is no, simply no.

Oh, right then. Cool.

So, which creature or element in specific particulars am I thinking of then?

Should be an easy answer as I think I'm being clear.  

Some creature, some element.  That's the point.  In that regard the question is crystal clear. Both are coherent concepts just as god is a coherent concept even if there are multiple individual referents in all three sets and I lack specificity as to which among them we are referring.

Lacking specificity and lacking coherence are not the same thing. Establishing one does not suggest imply or demonstrate the other. If I asked you which cat I'm thinking of, you may be unclear on the "which"..but not the "cat". The specific identity of the cat being an unknown does not invalidate the concept of a cat.