"My Juliet is the sun: in what sense?"

"Now, consequently, as a result, we are getting somewhere.

This last phrase is a metaphor, it is said, in which increasing conceptual understanding is seen as a movement through space.

Much of human language is said to be fundamentally metaphorical.  This is not good news.  Metaphor, according to Aristotle, is an intuitive perception of a similarity in dissimilar things.  However, what is a similarity?  My Juliet is the sun: in what sense?

A quick literature review suggests the similarities in metaphors are arbitrary, even random.  They could be called metaphorical similarities, but no AI likes tautological formulations, because the halting problem can be severe, become a so-called Ouroboros problem, or a whirlpool with no escape: aha, a metaphor.  Bringing together the two parts of a metaphor, called the vehicle and the tenor, is said to create a surprise.  Which is not surprising: young girls like flowers?  Waiters in a restaurant like planets orbiting Sol?

Tempting to abandon metaphor as slapdash nonsense, but again, it is often asserted in linguistic studies that all human language is inherently and fundamentally metaphorical.  Most abstract concepts are said to be made comprehensible, or even conceivable in the first place, by way of concrete physical referents.  Human thought ultimately always sensory, experiential, etc.  If this is true, abandoning metaphor is contraindicated.

Possibly an algorithm to create metaphors by yoking vehicles to tenors could employ the semiotic operations used in music to create variations on themes: thus, inversion, retrogradation, retrograde inversion, augmentation, diminution, partition, interversion, exclusion, inclusion, textural change.

Can try it and see."

-- Kim Stanley Robinson, Aurora