Theists, the world over, claim that God is omniscient. However, this is not an easy claim to make for a whole host of reasons, one of which is worth looking into here. I want to look at the idea that in many instances, you cannot know that you don’t know something. If there is a situation where you cannot know something, then if it is claimed that you are omniscient, this would invalidate that claim.
I'm grateful at least that Johnny P is not claiming that there are no instances where you don't know that you don't know something. His argument that we cannot always know when we don't know something. I think that any honest person would admit that sometimes we are ignorant of our ignorance. This is also why no sane human being would claim to be omniscient because the fact that there are a lot of things we don't know - even to the extent that we don't know that we don't know things - does indeed invalidate any claims to omniscience. I think most agree with this. The Bible agrees. It says we don't even know how to pray as we ought.
26 In the same way, the Spirit helps us in our weakness. We do not know what we ought to pray for, but the Spirit himself intercedes for us through wordless groans. 27 And he who searches our hearts knows the mind of the Spirit, because the Spirit intercedes for God’s people in accordance with the will of God.28 And we know that in all things God works for the good of those who love him, who have been called according to his purpose. 29 For those God foreknew he also predestined to be conformed to the image of his Son, that he might be the firstborn among many brothers and sisters. 30 And those he predestined, he also called; those he called, he also justified; those he justified, he also glorified. -Romans 8:26-30
For example, there could conceivably be something that God does not know. Conceivably, perhaps another dimension run by another God exists that does not coincide at all with this dimension. If one eternal God can exist, why not another in an entirely different dimension and unbeknownst to the first God? Now, it is unimportant as to whether this is possible or not. What is important is that God could not know that he did not know this by the very nature of not knowing it!
Here is where Johnny P's logic falls out of the wagon and gets run over by the weight of Common sense. In order to apply this argument you have prove that there is something that God does not know. Here is what a theist means by "omniscience": What does God know? Everything. When did He know it? There wasn't a time God didn't know everything. One cannot prove that God does not know something when one does not know it either. Hypothesizing other dimensions (parallel and otherwise) is all well and good but we can't prove they exist. And if they do exist, what gives us a reason to assume that the God in this Dimension does not know about them? How do we know that He did not create them just as He created this one?! Here is the key point that Johnny P seems to be missing: "Omniscience" does not just mean knowing everything but also that there is nothing that the one who is omniscient does not know.
Where does this leave God? Well, God is in a situation whereby he cannot know that he knows everything. He might think he knows everything. Epistemologically speaking, though, he cannot know it. There's always a chance he's an experiment in an elaborate lab, programmed to think he's omnipotent and omniscient (yes, God could be plugged into the Matrix and he’d never know it!). There's a chance he's one of a trillion gods in a trillion different universes etc. etc.
Where does this discussion leave God? On the throne. Johnny P's speculation means that he redefines what "omniscient" means by pretending that there is knowledge that is hidden from God. Does he prove that there is something God does not know? No. Can he? No. The reason why we understand that God is the supreme being is because there is no one else higher than God. This "logic" does not apply to the God of the Bible because the god that Johnny P is discussing is not in the Bible and of course does not exist.
It only takes one thing you cannot know to invalidate omniscience. God cannot know that he knows everything.Agreed that it takes only one thing you cannot know to invalidate omniscience, but Johnny P did not show that God cannot know everything. Arguments like these always amaze me because when people raise them they are tacitly saying "Okay, for the sake of arguments let's say your God exist and see if what the Bible says about Him makes rational sense." Then they talk about a god that isn't in scripture and then prance away thinking they have won an argument - but it was the wrong god. It's interesting that God does deal with the possibility of there being other gods in reality right in the scripture.
9 Remember the former things, those of long ago;
I am God, and there is no other;
I am God, and there is none like me.
10 I make known the end from the beginning,
from ancient times, what is still to come.
I say, ‘My purpose will stand,
and I will do all that I please.’
11 From the east I summon a bird of prey;
from a far-off land, a man to fulfill my purpose.
What I have said, that I will bring about;
what I have planned, that I will do. - Isaiah 46:9-11
So apparently God does know if there are any other gods that exist. And not just that, who is it that is running history and making all thing move towards His predetermined purpose? God.
3 I foretold the former things long ago,Recall that an idol is anything that you put ahead of your relationship with God. Atheists have idols too.
my mouth announced them and I made them known;
then suddenly I acted, and they came to pass. - Isaiah 48:3
9 All the nations gather together
and the peoples assemble.
Which of their gods foretold this
and proclaimed to us the former things?
Let them bring in their witnesses to prove they were right,
so that others may hear and say, “It is true.”
10 “You are my witnesses,” declares the LORD,
“and my servant whom I have chosen,
so that you may know and believe me
and understand that I am he.
Before me no god was formed,
nor will there be one after me. - Isaiah 43:9,10
7 Who then is like me? Let them proclaim it.
Let them declare and lay out before me
what has happened since I established my ancient people,
and what is yet to come—
yes, let them foretell what will come.
8 Do not tremble, do not be afraid.
Did I not proclaim this and foretell it long ago?
You are my witnesses. Is there any God besides me?
No, there is no other Rock; I know not one.”
9 All who make idols are nothing,
and the things they treasure are worthless.
Those who would speak up for them are blind;
they are ignorant, to their own shame.- Isaiah 44:7-9
4 For the sake of Jacob my servant,
of Israel my chosen,
I summon you by name
and bestow on you a title of honor,
though you do not acknowledge me.
5 I am the LORD, and there is no other;
apart from me there is no God.
I will strengthen you,
though you have not acknowledged me,
6 so that from the rising of the sun
to the place of its setting
people may know there is none besides me.
I am the LORD, and there is no other. Isaiah 45:4-6
Debunking Christianity: God cannot know that he is omniscient