Oh I didn't realise sorry. In that case then, it's possible. I'm almost certain there are smarter and better "beings" out there somewhere, but even they  must have some sort of limit to something

Fuckin magnets!!! How do they work?

More importantly :

can an incandescent omnipotent and invincible being cook a pizza so ho that even he cannot eat it ?

Its the fundamental difference between having an objective and a subjective view. In our world, I can say that I don't know what I don't know becuase I have a perspective that is limited by both time and place. There might always be some unobserved instance that I cannot view. An omniscient being, by definition, must exist outside time and space. The reason it knows everything is because it can observe all possible states of the world from a "distanced" perspective (I always though Nagel's "view from nowhere" was an apt discription). The reason there are no constraints on its knowledge is the fact that all observations are in its frame of reference at one time.

In terms of the quote you provided, its focusing on the justification aspect of knowledge. The problem is that not all knolwledge can be justified. This was realized as far back as Aristotle. You would essentially have an infinite chain of argumentation where you keep searching for a justification for each subsequent justification. This is what has led to the idea of foundationalism-the idea that our knowledge is grounded on foundational truths, untestable beliefs (the obvious ones being the rules of logic) that we take as self-evident. The same thing would happen if you kept asking an omniscient being to justify thier knowledge-the argument has to end at some point and would rest on a foundational view of knowledge.

I could say some more, but I think two paragraphs are good for now. : )

An all-knowing being knows everything by definition. Knowing everything, it therefore knows that there is nothing that it does not know. If it did not know that it did not know everything, there would be a thing that it did not know, and so then, such a being would not be an omniscient being; rather, such a being would be a step below an omniscient being, who must, by definition, know everything, including that it does indeed know everything, perceiving with perfect understanding that all of the contents of its knowledge are not contradictory, including this thought element. Such a being would not even question its perfect knowledge, understanding that its perfect knowledge of all is entire and that there could neither exist nor subsist anything apart from this knowledge.

Your attempt at a contradiction was itself a contradiction. Thread ended.

Your question contains within it a contradiction and so the premise is false.

That's the joke....

Well said. That was essentially my other criticism. Asking an omniscient being to admit that it doesn't know something is actually asking that being to contradict its nature. Its essentially asking a being to know everything but not know everything at the same time.

My honest, and deeply thought out evaluation on this topic is the following......

Some people think way too much.

Thank you zarx

and a little hommage to a the forbidden simpsons episode where Homer asks Flanders if god would be able to "heat a pizza so hot that even he could not eat it".