Metaphorical transfer is the process by which properties that belong literally to one domain are applied metaphorically to another, enabling expression in Goodman's technical sense. Sadness belongs literally to conscious beings—it is a state of human emotional experience. A painting cannot be literally sad; paintings do not have emotional states. But a painting can be metaphorically sad—it can possess sadness as a transferred property from the emotional domain to the visual domain, and it can exemplify that metaphorically possessed property by highlighting the formal features (grey tonality, downward compositional movement, spatial emptiness) through which the transfer is effected. The transfer depends on conventions that establish which formal properties in the metaphorical domain correspond to which qualities in the literal domain. The conventions are learned through immersion in aesthetic practice—centuries of looking at grey paintings and finding them expressive of somber emotions install the association between grey and sadness. The transfer is not natural or automatic; it is culturally constructed, historically variable, and requires perceptual education to be perceived. But once perceived, it provides understanding of the emotional quality through the specific symbolic means by which it is expressed—understanding that is irreducible to verbal description or scientific analysis.
Goodman developed the metaphorical-transfer account of expression to replace the Romantic transmission model, which treated artworks as vehicles for communicating the artist's emotions to the audience. The transmission model is psychologistic—it locates aesthetic value in mental states rather than in symbolic functions—and it is empirically questionable (artists often produce works expressing emotions they are not currently feeling, and audiences often perceive expressive qualities that do not match the artist's emotional state at the time of production). Goodman's alternative: expression is a property of the work, not of the artist. The work is metaphorically sad because it possesses and exemplifies formal properties that convention associates with sadness. The artist's emotional state is irrelevant to the work's expressive achievement, in the same way that a tailor's feelings about red are irrelevant to whether the swatch exemplifies redness.
In the AI age, metaphorical transfer can operate at the conventional level without the experiential grounding that gives expression its cognitive depth. A diffusion model can generate images with formal properties that convention associates with emotional qualities—it can produce grey, weighted, spatially empty compositions that viewers perceive as sad. The transfer operates because the model has absorbed the conventional associations from its training data—millions of images tagged or described in ways that correlate visual properties with emotional labels. But the correlation is statistical, not experiential. The model has not lived through sadness, has no embodied knowledge of what sadness is, possesses no purposes that would determine why expressing this particular configuration of sadness in this particular visual form is worth doing. The transfer achieves surface expression—the viewer perceives sadness—without the depth expression that requires grounding in the worldmaker's lived engagement with the emotion being expressed.
The result is expression that is conventionally correct but existentially empty—form that has been optimized for the appearance of expressive rightness without the experiential substance that makes expression cognitively valuable rather than merely perceptually effective. The viewer who perceives sadness in an AI-generated image is not perceiving wrongly—the metaphorical transfer is operating as convention specifies. But the viewer may be attributing to the image a depth of expressive achievement that the image's productive process did not involve, because the depth depends on the image being embedded in a worldmaking project grounded in lived experience, and AI-generated images, unless directed by a human worldmaker with such grounding, possess the form of expression without the existential weight that makes expression matter.
Metaphorical transfer is analyzed in Languages of Art, Chapter II, section 5, building on Goodman's earlier 'On Likeness of Meaning' (1949) and 'On Some Differences About Meaning' (1953). The framework integrated his work on metaphor with his analysis of exemplification to provide a non-psychologistic account of how artworks can possess and refer to emotional qualities. The analysis has been challenged by theorists who argue it cannot account for the phenomenology of emotional engagement with art, but it has proven influential in cognitive approaches to aesthetics and in philosophical accounts of how formal properties carry affective content.
Properties transfer from literal to metaphorical domains. Sadness exists literally in human consciousness and metaphorically in visual/sonic properties—enabling artworks to possess emotional qualities they cannot literally have.
Transfer is conventional. Which formal properties correspond to which emotional qualities is established by cultural convention, learned through perceptual education, historically variable.
Grounding in experience matters. Deep expression requires that the metaphorical transfer be grounded in the worldmaker's lived experience of the emotion—convention without grounding produces surface expression without cognitive depth.
AI achieves convention without grounding. Models can deploy formal properties that convention associates with emotions, producing perceptually effective expression that lacks the existential weight genuine expression requires.