Scope note: This symmetric property allows the instances of E53 Place which share common borders to be related as such. This property is purely spatial, in contrast to Allen operators, which are purely temporal. Examples: - Scotland (E53) borders with England (E53) In First Order Logic: P122(x,y) ⊃ E53(x) P122(x,y) ⊃ E53(y) P122(x,y) ⊃ P122(y,x)