But when we consider the analogy between water waves and sound propagation, we are trying to build an isomorphism between two internal models. Implicitly, we are acting as if our model of water waves can be used to modify and improve our model of sound. Metaphors and analogies move novices', childrens' and experts' mental models into to the unknown. The use of metaphor and analogy is therefore a weak, or general heuristic, dependent on mental models of the source and target domains for its success. Let us consider an example.
Experts frequently use analogies to build bridges from the known to the unknown.
This metaphor is powerful, but researchers need to remember it is a metaphor. An even more common metaphor is that brain corresponds to mind. Metaphors are only dangerous when they are confused with Truth. For example, the computer I am using to write this contains portions of my memory, in the form of references, related articles, diagrams, and schedules. I could argue that important aspects of my mind are not in my brain.