A Boundary is wise to keep — A fence between makes love more keen.

The Boundary is requisite to conflict — spatial boundaries are evident in every finite conflict.

A Boundary is, in political geography, an imaginary line between two nations, separating the imaginary rights of one from the imaginary rights of the other.

A Boundary is a divider, real or imagined, designed to enforce civility. See "failure".

The Bridge is not always possed of an other side. Crossing is all that matters.

A Bridge is literally a bridge through space and time.

A Bridge is a hallway

A Bridge has no allegiance to either side.