i.e. BPs whose "world" is left examples for BP537.
Bongard Problems whose "world" is Meta Bongard Problems vs. other Bongard Problems.
i.e. BPs that sort all BPs that are left examples for BP537.
Bongard Problems whose "world" is Meta Bongard Problems.
i.e. BPs that sort what fits in BP537.
Bongard Problems that sort Bongard Problems that sort Bongard Problems.
i.e. BPs that sort BPs in BP537.
i.e. BPs that sort BP537.
This is the keyword "metameta" on the OEBP.