Metaphor allows us to think about, draw conclusions about, or experience one thing in terms of something else. Metaphor maps not only attributes and relationships but inference patterns from the source domain to the target. These mappings are not random but have a specific structure that shape interpretation and inference. This structure is best expressed as a set of narrative relationships with inherent expectations, possibilities, and hoped for outcomes. One helpful shorthand for these narrative relationships comes from a Lithuanian-born French structuralist named A. J. Greimas.
Greimas’ Actantial Model
The narrative structure expressed by this “actantial model” organizes material in the source domain and then maps this narrative structure, with attendant presuppositions and inference patterns, onto the target domain. The effect of this cross-domain mapping is to reorganize and highlight some aspects of the target domain while minimizing other aspects. Metaphor allows us to reason through one thing in terms of something else through this mechanism of cross-domain mapping.
Cross-Domain Mapping and Narrative Structure
We don’t map random lists of characteristics from the source to the target; rather, the relationships, possibilities, and hoped for outcomes in the source map as relationships, possibilities, and hoped for outcomes to the target. That’s why metaphor is never completely exhaustible or reducible to s simple list of propositions.
Though metaphor interpretation is open, it is not random. The narrative structure implied by the metaphor shapes how the metaphor is understood and what inferences are sanctioned by the metaphor. We map narrative structure from the source to the target. Metaphors that share the same language may have very different narrative structures. The differences between “I am Jesus’ Little Lamb” and “Behold, the lamb of God who takes away the sin of the world!” is not merely a matter of vocabulary, but of narrative strucutre.
For a more detailed description of Greimas’ actantial model and how the dynamics it expresses can be used for metaphor theory, please see chapter 2 of my PhD dissertation, Chapter 2 A Narrative Approach to Metaphor.