" Mental progress stops when the mind is
blocked on its path, and a new mental path is needed. Imagination is the formation
of an image, something that the mind can “see,” and which therefore provides a
form of knowledge. Imagination can be understood via this metaphor as the power
to arrive at knowledge by constructing an image, say, an image that allows one to
overcome blockage by reperceiving the situation unconventionally. We say, for
example, “Use your imagination to find some way around this impasse. "

― George Lakoff , More than Cool Reason: A Field Guide to Poetic Metaphor