This is a joke about building castles in the air, which means “To create dreams, hopes, or plans that are impossible, unrealistic, or have very little chance of succeeding”.
So, what’s the difference between a neurotic, a psychotic and a psychiatrist?
A neurotic is the person who builds a castle in the air.
A psychotic is the person who lives in it.
And a psychiatrist is the person who collects the rent.
Sounds pretty accurate to me, what do you think?
Image used under a Collective Commons License from https://www.pikrepo.com/nvvse/brown-concrete-castle-under-blue-sky-during-daytime