"For a while these reveries provided an outlet for his imagination; they were a satisfactory hint of the unreality of reality, a promise that the rock of the world was founded securely on a fairy’s wing."

Why, that's a sentence from "The Great Gatsby." Couldn't you tell?

The unreality of reality... the world... founded securely on a fairy’s wing....

So... I Googled "unreality of reality," and the second thing that came up was a Wikipedia article titled "Reality in Buddhism."

Some consider that the concept of the unreality of "reality" is confusing. They posit that, in Buddhism, the perceived reality is considered illusory not in the sense that reality is a fantasy or unreal, but that our perceptions and preconditions mislead us to believe that we are separate from the elements that we are made of. Reality, in Buddhist thought, would be described as the manifestation of karma^{[citation needed]}.

Isn't it always like that? Citation needed!