Before I started graduate school, an invention was the work of a scientist, engineer, or eccentric tinkerer. It involved knobs, wires, dials and levers. It was man-made object (generic specificity intended) that was primarily technological: if not mechanical, then electronic.
In my occasional exposures to rhetoric, invention (or, more often, inventorio) is described as the stage when a writer (or orator) brainstorms ideas before structuring them into an argument. In composition, this has come to be associated with prewriting. But prewriting had a particular orderliness imposed on it: outlines, graphic organizers and diagrams were often suggested as ways to organize disorderly thoughts in the same way that an inventor drafted blueprints or meticulously labeled parts.
I have come to see invention as synonymous with creativity or imagination. In place of a metal box with dials and knobs I see a dancer improvising steps, a chef combining familiar ingredients in new ways, a poets walking through a woods, her focus divided between the landscape surrounding her and the words forming a chain of sound and meaning in the recesses of her mind. Invention becomes a playful activity, a mode of living, that invites joy and wonder and occasionally feels miraculous, but is open to every person with the capacity for curious dreaming.