See @leftright.
All "updown" Problems are @handed.
Left-sorted Bongard Problems have the keyword "updown" on the OEBP.
Visual Bongard Problems such that flipping over horizontal axis (up/down) can switch an example's side vs. visual Bongard Problems whose examples' sorting does not change under such a transformation.
Visual Bongard Problems such that flipping over horizontal axis (up/down) can switch an example's side vs. not so.
See left-BP535 for "leftright".
All "updown" Problems are "handed" (left-BP552).
Handed visual Bongard Problems such that flipping over horizontal axis (left/right) can switch an example's side vs. not so.
Aaron David Fairbanks