[murrayh]

Sorry, I should have explained myself.

The literal interpretation of the challenge is a paradox. The contradiction is that a secret is no longer a secret once revealed (hence my comment).

I don't think that is what you were trying to convey. You do raise a valid point, but without any supporting evidence, it is thoroughly unconvincing. The absence of X is not enough to conclude that X does not exist (especially when X is being purposefully hidden, as in this case).

NOTE: I am not disagreeing with you. I don't know whether or not secret rich people exist.