In The Way We Think, Gilles Fauconnier and Mark Turner argue that the human capacity to do Conceputal Blending is at the heart of creativity, imagination, language etc.. They provide a wealth of detail and examples to support this claim.

In this view, phenomena that had been hard to cope with in classical linguistics, such as counterfactuals and metaphor, are seen as cases of a more general human cognitive capacity, Conceptual Blending.