Ghosts in DST, what are they?

[Pop Guy]

Can the mind survive without a body? And if so, then why does a body "exist"? If in the fantastic vision of Don't Starve the ghosts are real, why do these souls "reincarnate"?
Perhaps the phantom condition is a condition of perpetual pain that only a body of "flesh and blood" can soothe?
Perhaps "incarnation" is a punishment from some wicked sadistic god, similar to "Them"?
Personally I don't think Klei ever asked himself these almost philosophical questions, but I have my own theory that I think is quite interesting.
Ghosts in Don't Starve aren't really ghosts. Let me explain: Shadows, we can guess, are not really ethereal "shadows": they have physical limits when they appear; they can be hurt, they can interfere with the physical world. But being from another dimension, it is as if our senses could only perceive its mirage. Like a shadow hidden by a veil, in fact.
What if ghosts were also "partial" manifestations of human bodies trapped in another dimension? We know that there are other realities beyond the Constant, countless distorted realms where leviathans dwell. What if Abigail and the ghosts can't be brought back to life because they just aren't really dead?
What can wait eternally is not dead, and after strange eons even death can die...

[thegreatJash]

They are souls lost from their body.

[Russian_Philin]

To be honest, I think that ghosts are just the restless souls of dead people that THEY have dragged into this terrible world. Graves, I think, are probably the graves of the people who died in the San Francisco earthquake. Or THEY kidnapped a lot more people from behind a hole (Maxwell's mysterious artifact and portals) in two worlds, so many died and couldn't survive.
Or I have another guess. All the ghosts and graves are THEIR failed attempts to find the physical shell. I understand that THEY can't physically affect the world, so THEY use living beings as a shell. They could experiment with it for a long time.
In general, these are just my thoughts.