Philosophy and literary criticism go wrong when we refuse to acknowledge that things are there, that the world is real. "I think, therefore I am" implies that to think is not a transitive verb. But it is. You can't "think" in a vacuum any more than you can breathe in a vacuum. You cannot breathe without air and you cannot think without thinking about something. Therefore, if "I am thinking", then both "I am" and "it is". Anything other than that leads to a slow madness.
This applies to the odd little argument over at the Christian Shakespeare. If a thing cannot be known for itself, then the things related to that thing cannot be known, and the things related to those things cannot be known, ad infinitum.
Perhaps when God told Moses that He (God) was called I Am, He was speaking to the modern age. God exists, and therefore everything is real. "He is, therefore we are."
But all of that narcissistic onanistic self-aggrandizing solipsism is simply Unreal.