The traditional definition of metaphor is based on similarity. Jakobson associated metaphor with semantic similarity (and metonymy with semantic contiguity). According to Wiktionary, metaphor is “The use of a word or phrase to refer to something other than its literal meaning, invoking an implicit similarity between the thing described and what is denoted by the word or phrase.” Yet similarity is often deemed an inadequate basis for defining metaphor since it does not capture the fundamental and generic role of metaphor in the production of meaning in language.
Here I would like to do the obvious Lacanian thing to do (which surprisingly nobody seems to have done) and associate similarity with the imaginary aspect of metaphor. Similarity is not simply a deceptive and wrong basis for defining metaphor, instead it succeeds in designating the deceptive and imaginary aspect of metaphor.
There is also a symbolic aspect of metaphor that is orthogonal to the imaginary similarity. In the Wiktionary definition above, this symbolic aspect is signified by this phrase: “something other than its literal meaning” or “not literal” in short.
A metaphor superficially evokes an imaginary similarity, but simultaneously the same metaphor unconsciously makes a symbolic gesture in the field of literality to create new meaning. However, this truly significant symbolic gesture is concealed and negated by the imaginary similarity that occupies the conscious perception of meaning. Here’s a matheme to represent these two aspects of metaphor:
We can easily translate this structure into Lacan’s L Schema:
When the subject’s use of a metaphoric signifier invokes the Other of language, two simultaneous events take place:
1) Similar: In the field of conscious meaning, an imaginary similarity is evoked between the metaphoric signified and the subject’s intended meaning.
2) Literal: In the field of unconscious signification, a gesture is made to create new symbolic associations of literality.
Since the evocation of similarity represses the gesture of literality, we officially state and accept that metaphors are “not literal” even though they are unconsciously so.
Finally, let us examine this structure in Lacan’s famous paternal metaphor which substitutes the Name-of-the-Father for the mother’s desire. The conscious meaning of the nuclear family is occupied by the imaginary similarity of the paternal metaphor that says:
“The mother is like the father.”
But the truly significant gesture that founds the family is given by the symbolic literality of the paternal metaphor that says:
“The mother likes the father.”