> “Reality is that which, when you stop believing in it, doesn’t go away.”

Funny thing is that it seems to apply to intersubjective phenomena too. For example, a "limited liability corporation" is made entirely out of shared delusions of people, but is a real thing under this quote, in the sense that it remains even if you or I stop believing in it. However, if sufficiently many people stop believing at once, it will go away.

(And so will things like money, rule of law, or civilization.)