A fork of Rural Dictionary
The idea that you are only conscious that you exist, as you are conscious, everything else could be fake, and all a part of your own thoughts, an idea that you only are sure that you exist. Derived from Cogito ergo sum.
Person 1 - "Yo bro do you exist" Philosopher- "I think therefore, I am" Person 1 - "Huh?" Philosopher - "As far as I'm aware, but by that philosophy, you will never know if anything but you exists :)" Person 1 - "...oh"