Let's say that there is a file system containing all this content.
Let's then say that you have your own computer (your soul) which is networked into the file system (via the christ mind which connects the souls).
Let's say that because the system is "open", other souls also can hook themselves up to the file system (via the christ mind).
And let's also say the system is so open that anyone who connects themselves to the file system also becomes "part of" the system, and their system is open, and so it allows access to their own computer by the main filesystem and also by all the other computers (souls).
In this open environment (heaven/sonship), I can access a file, say a pdf file, on the file system, and have full access to it. I can read the whole file. Simultaneously, you and other souls can access the same pdf file, and have full access to it, and share it, at the same time, and read the whole thing without limits.
Similarly I can access YOU, the file on your own computer (soul), and fully access everything about you and share "what you are", including any "creations" which you might have stored "inside" your own computer (within your being).
And as such in this open state, the entirety of creation is accessible to everyone simultaneously, fully, and without restrictions. Everything is shared. No-one is denied access. Everyone can access everything fully, even if others are accessing the same content, at the same time. Our access overlaps.
Consider the separation idea, or the ego. What would happen if you suddenly became selfish, and decided that you wanted access to one of the files on the file system, to have the same full access you had before, BUT... with a condition.
The condition is, that no-one else is allowed to access it at the same time as you. You want exclusive rights. You want ownership. You want the content to be isolated. You want to keep others away from the content and not share it with them. And to do this you have to put a "wall" of some kind around the little piece of content to a) keep you inside of it where you can access the content, and b) keep others outside of it so they can't access it.
Now, let's say that rather than you doing this with a file on the main filesystem, you instead try to do this with your own computer (soul). Let's say you try to make it so that you have access to your self, but other souls don't. That the main file system is also deprived access from your computer, and no-one is allowed to share what's on your computer. You want a "private" system.
So you put up a wall around your computer (the body, around the mind) to try to keep you in and others out, so that you can have exclusive rights and possession of what is "inside" you and reject what now seems to be "outside you" (the rest of the network/sonship). You're now being selfish. You've put yourself into lockdown. You have shut yourself off from SHARING with the whole, from the network, and from the main filesystem, and so all you are left with is what's inside your own system.
In this state now, you are still basically the soul, the self, which you were before this happened. In this act, you did not actually invent a self. You already were a self, when you were sharing the filesystem, as God intended. Openly. But now that you put a wall around yourself, this makes "your self" become "separate". It's like you unplugged your computer from the network so that no-one else could share what you have.
So this produces "a self which has BECOME separate", which previously was not separate. This is what "the separate self" means. THIS *SELFISHNESS* is the EGO. Not the idea of a self or soul.... the idea of a self or soul that has become trapped in isolation due to the walls its put up, the blocks to awareness, which have disconnected and disassociated itself from sharing with the whole networked system. So now you are a perfect being surrounded by limitation. The limitation needs to be removed, not your SELF.
In fact, in order to "wake up" from the state, you need to plug your self back into the network (sonship) and re-join with the whole system (heaven), by plugging your computer (soul) back into the network via a cable (christ mind) so that you can share the whole system again. And this also means the whole system now has access to YOU as well, because you are part of the content. Literally this means that a part of the sonship, a part of creation, which was orphaned, is now returning to the whole, so that the whole can now SHARE IT and access it and therefore benefit from and enjoy it (you) just as much as you enjoy others.
So you see just like with computers, which host NON-PHYSICAL content, Heaven also hosts non-physical content. And in that kind of system it's possible for us to SHARE and have simultaneous access with everyone else, without anyone being limited or restricted or shut out in any way. This is the nature of Heaven, God's creation. It's all based on openness and sharing by many individual souls who ALL have FULL access to the WHOLE of everything all at once.
Your soul has full access to everything, and to the ego that would mean "there is nothing left" for anyone else. But to God, your full access means everyone else ALSO can share and have everything. Just not exclusively. There is no exclusivity, isolation, SPECIALNESS or selfishness in heaven. It's a totally 100% open shared system of freedom.
ACIM: "The ego is the idea of selfishness. The soul is the idea of self fullness."