This project assumes we can know things that are not really knowable for everyone. It starts with gender and birthplace, both tricky questions in some situations.
So maybe we get to assume we have some oracle that helps us simplify the hard questions.
At that stage, it's easy. Begin with, "Assume we build a list of people sorted by time of birth (with some arbitrary tiebreakers, like proximity of birthplace to Barbados, or darkness of hair color...)."
Question 1: Are you on the top half or bottom half of this list?
Question 2: Are you on the top quarter or bottom quarter of the half?
Question 1: Are you north of an east-west line that perfectly divides the population in half?
(proceed to continue to divide each section in half.)
Of course, determining the position of those lines is damn near impossible. And as soon as someone hops on a plane, the whole thing comes crashing down.
I like it. Maybe "were you north of an east-west line" when this list was made.
I guess it gets tricky when people are born.
Wait a minute, just realized this whole question breaks down if we don't recycle numbers from the dead back to the newly born... and there's no guarantee that all of the dead will sufficiently resemble all of the newborns. I want my money back. :)
So maybe we get to assume we have some oracle that helps us simplify the hard questions.
At that stage, it's easy. Begin with, "Assume we build a list of people sorted by time of birth (with some arbitrary tiebreakers, like proximity of birthplace to Barbados, or darkness of hair color...)."
Question 1: Are you on the top half or bottom half of this list?
Question 2: Are you on the top quarter or bottom quarter of the half?
Question 3: ...