Winner of Thunderdome 2018-2019: Day 4. See the prompt here.

Open a human up, and there’s just another one inside. Like dolls on a shelf in a shop you wandered into by chance, in a place where your tongue is not spoken, and thus hardly seems real.
The first layer is the mask—constructed, a work of art, a work of fiction. It declares to the world: I am me.
But you are not you.
Inside is a second you, a realer you. This one the self might recognize, though the world would not. This one’s in charge, or so it tells itself. It watches through the eye-blanks of the mask, and thinks itself very wise.
Peel it away. It is arrogant, and unneeded. Go deeper.
The third you is a mess. It is all things at once and yet it is nothing. A taxonomy of selves. Different flavors of blood to pour into the veins. Today, I think I’ll try man. Tomorrow it may not suit me.
The fourth is foundational, and unrecognizable. A house is more than just the wooden frame, though the whole project may collapse without it. Maybe these are bones, or something far older.
Discard them.
The fifth you is smaller and wispier than a ghost. When exposed to harsh light, it may fall away to ash, so you must protect it. This one has been with us from the very beginning, and with a voice lighter than mist, it reminds you of your impermanence.
You could root around for a soul, but you won’t find one. If there is a soul, it is untouchable.
Now to put it all back together. What, have you forgotten where the pieces go? A terrible scientist, this—who can dissect and not mend. Your patient is waiting.
Dolls stacked within dolls. It’s as hopeless as that.