Left-sorted Bongard Problems have the keyword "side" on the OEBP.
Right-sorted Bongard Problems have the keyword "sideless" on the OEBP.
Here "flipping the sides" of a Bongard Problem does not flip the sides of the example BPs.
Metaconcept implies "sideless".
Adjacent-numbered pages: BP534 BP535 BP536 BP537 BP538  *  BP540 BP541 BP542 BP543 BP544
meta (see left/right), links, keyword, right-self, sideless, invariance, metameta, left-it, feedback
Aaron David Fairbanks