Shankara chari and te dactina, mutistotra he s visam, anagarituliam, nijantar gatam, like a city. In the fictional universe, there is a sense of isiness associated wi reality. Reality and isiness are the same thing. And this isness is in everything that we experience. Just like all the waves and ripples in that beautiful lake water is. Even a num, something like an abstract concept like a number, is in some sense, even fictional entities.
Inspired by the 15th chapter of the Ashtavakra Gita, Swami Sarvapriyananda gives a discourse on the nature of the Self.