"I" is just the one who says "I"

A pure performative entity.

The Lacanian subject of the enunciation.

The Cartesian cogito is the subject of the unconscious.

Slavoj Zizek

"The Cartesian subject versus the Cartesian Theater"

in Cogito and the Unconscious

(Slavoj Zizek ed,), Durham, Duke University Press, 1998, chapter 9.