the issue is really whether the Self is all that exists or not.

and how would you know if it wasn't?

as he says, "we have reason to believe" the Self isn't everything.

thats already a leap.

but a generally accepted one.

so if we accept for the moment that there are "reasons to believe"

what is the nature of that Other? what order does it have and how is it known?

you know, philosophy.