i wish that someday "the map is not the territory" would supersede plato's cave as the most popular philosophical metaphor. we each create models of the world around us, and if there's disagreement, we can check, and reality decides. classical platonism would be that the "territory" is just shadows cast on the walls of the cave, but the map is the Eternal Truth. (and descartes might say we can't know the territory for sure, etc baudrillard etc)
i've always had a bit of a thing for compasses since i was a kid, in part because i have a terrible sense of direction. then sometime in grade school i learned how to find south with a wristwatch and sunlight, one of my favoritest tricks ever. native skills weren't enough, but hey, we're a tool-using species, so there. and magnetic declination for manila is 1 degree 20 minutes west of true north. i looked it up.
back in high school, i played Xenogears (probably my all-time favorite videogame) and while many games would have a little wireframe map in the corner of the screen, Xenogears had a compass. it worked too. i remember an area that was like this huge underground supercollider tunnel, and i just kept running along a long endless corridor curving to the right. but with the compass, ok, i could see that i was in the quadrant from, say, 3 o'clock to 6 o'clock.
greg egan's schild's ladder had a morality-as-geometry metaphor, though i didn't really see the need for the crazy tongs constructions. just use a compass, it's still a valid analogy. a compass helps you orient, dispels a small bit of confusion, lets you know your relationship to objective points of reference.