During World War II allied armies marched into Germany on their way to Berlin. Retreating German soldiers switched road signs and destroyed landmarks in an effort to confuse their enemy. And, to an extent, it worked, for many a G.I. followed a false marker only to end up in the wrong place. That just goes to show the need for landmarks, the importance of reliable signposts by which to steer.

Here locally, landmarks like the courthouse, the river, the college, or the bridge are important in helping us find our bearings. Why, if some villain came in one night and removed our signposts, the next day would become a bewildering jumble of uncertainties, and we'd all be lost. 

The text is about landmarks. It refers to the Jewish custom of setting boundary stones to mark out property. Just as …