BPs whose left-sorted examples exhibit the following property: if a square region of any left-sorted example is replaced with any other left-sorted example, the resultant image is also sorted left vs. BPs whose left-sorted examples do not exhibit this property.

BPs whose left-sorted examples exhibit the following property: if a square region of any left-sorted example is replaced with any other left-sorted example the resultant image is also sorted left vs. BPs whose left-sorted examples do not exhibit this property.

Leo Crabbe