Left-sorted Bongard Problems have the keyword "easy" on the OEBP.
Right-sorted Bongard Problems have the keyword "hard" on the OEBP.
"Easy" means easy for human beings to solve, not computers.
"Easy" means easy for human beings, not computers.
Easy Bongard Problems vs. hard Bongard Problems.
"Easy" means relatively easy for humans to solve.