This prompts thinking about @left-self and @right-self keywords.

This prompts thinking about @left-self and @right-self keywords.

BPs in BP788 are ambiguous examples.

This prompts thinking about +self and -self keywords (BP517).

BPs in BP788 are ambiguous examples.

This prompts thinking about +self and -self keywords (BP517).

Meta Bongard Problems fitting in their own world vs. other meta Bongard Problems.

Bongard Problems with world "bp" (left-BP524) or world "metabp" (left-BP527) always fit on the left side here.