Metaphor requirements

When I teach, I use examples from grocery stores to explain wayfinding principles. It works really well.

This metaphor works wonderfully. People almost immediately make the jump to pointing out additional things grocery stores do to improve wayfinding.

You know where it doesn’t work? Europe. Urban European grocery stores are totally different, and they don’t do any of the same things, so they’re no good for teaching wayfinding.

Metaphors work for teaching or improving usability when a familiar, concrete source domain’s characteristics have significant overlap with a new, abstract target domain.

American grocery stores don’t help teach wayfinding principles in Europe because they aren’t familiar to a European audience. Urban European grocery stores don’t help teach wayfinding principles in Europe because they don’t have enough overlap with the principles to illustrate it well. To go a different direction, color theory might be familiar to a group of people, but it won’t help teach wayfinding, because it’s not concrete enough.

For a metaphor to work, you’ve got to have all three: Familiarity, concreteness, and overlap.

Q: I got “familiarity, concreteness, and overlap” from somewhere, and I now cannot find the source.