My awkward name for the theory of metaphor based on an assumption that language is about conveying truth statements from one brain to another.
A summary of John Searle's essay "Metaphor" in Andrew Ortony (ed.), *Metaphor and Thought 
* (2/e), 1993.
The setup is an imaginary conversation where Dawn is telling me about Helper T cells , part of the grotesquely complicated immune system.
A model for the activation of Helper T Cells. Public Domain 
.
Let's pretend that, when she finished, I said “That went completely over my head.”
That seems like a crazy way to say “I didn’t understand anything you just said.” Searle provides a description of what my brain does with the original statement: a fairly mechanistic process.
First, normal conversations have rules. One of the rules is that what you say should be relevant, isn’t a non-sequitur. So Dawn’s brain, hearing “That went completely over my head,” has a “huh?” moment. “Why is Brian babbling about things flying over his head?” Because I’m a norm-following conversational partner – that’s what first attracted Dawn to me – her brain knows that I mean to convey to her something that’s true and relevant by using something untrue and irrelevant. Essentially, I’ve set her a puzzle to solve. She solves the problem by thinking about properties of the fictional situation, and wondering how similar properties might apply to the actual situation.
So, “over my head” means “not in my head,” which implies “not in my brain,” which means the message wasn’t received, which means understanding wasn’t achieved.
Searle devotes only one paragraph of a 28 page essay to explaining why I would want to make Dawn go through all this.
“The expressive power that we feel is part of good metaphors is largely a matter of two features. The hearer has to figure out what the speaker means – he has to contribute more to the communication than just passive uptake – and he has to do that by going through another and related semantic content from the one which is communicated. And that, I take it, is what Dr. Johnson meant when he said metaphor gives us two ideas for one.”
Boom, end of essay
In other words, I’m giving Dawn work to (1) make her pay attention and (2) to remind her that objects can move through the air roughly horizontally, and sometimes pass above a fixed point of reference, such as a head.
The first seems rude, and the second pointless, so I don’t buy it. I favor Conceptual Metaphor.