So me and the wife were talking the other day about conspiracy theories and delusions. Conspiracy theories are basically out there ideas that people believe in regardless of how real or plausible they really are. So when does believing in conspiracy theories start to become delusions? Who draws the line? Not all people who believe in conspiracy theories are delusion and not all delusional people are conspiracy theories nuts.

The wife thinks the plausibility of the conspiracy theory is what determines if it's a delusion or not. For example, it's completely plausible that the gov't could have killed JFK. Where as believing in Elvis, Tupoc, and Michael Jackson are still alive together somewhere in seclusion is probably a delusion.

What about believing in the matrix? Is that a delusion? Is it really plausible? Who determines if it's plausible?

So my question is, when do y'all think a healthy belief in conspiracy theories actually become delusions? Or is believing in conspiracy theories just a delusion to begin with? What's y'all thinking?