Of the 33 secrets, I think this one, "Try living for a week on $2 a day", may hold the very secret to our survival as a species.
Contemplating . . .
. . . are there any creatures other than Human's who depend upon a monetary system to acquire their most basic survival needs such as food and shelter?
. . . is this unique to us?
. . . is currency exchange an evolution or a devolution in the behavior of living organisms?