In this paper, I argue that we can usefully distinguish between two types of metaphor creativity, the poetic and the prosaic. Following from Bakhtin's distinction for language more generally, the prosaic concerns the ordinary and everyday use of language, whereas the poetic involves the deliberate crafting of language. The prosaic is unfinalisable, dialogic and shared; the poetic is completed, non-dialogic and distanced. Creativity in each case is different in nature.
To elaborate the distinction between poetic metaphor creativity and prosaic metaphor creativity, I present data from studies of the discourse dynamics of metaphor in conversations and in composing poetry. Prosaic metaphor creativity is shown in action as people develop their own and other people's metaphors in the flow of talk. The strategies they use to do this reveal something about the affordances of metaphor that are exploited in poetic metaphor creativity. In analogy with 'found art', prosaic metaphor creativity in conversation yields what we might call 'found poetic metaphors'; it is argued that a poetic process is still involved but that it has shifted from the creating to the finding. Drawing on published reflections by poets Seamus Heaney and Mark Doty, I illustrate how poetic metaphor creativity deliberately intensifies symbolism and enriches affordances for metaphorical remindings and connections, while resisting conventionality.