 It is easy to lose sight of metaphorical pretense. We may mistake the model for a real instance of what it models, drift from make believe to outright belief, confuse the mask with the face beneath it, take literally what was originally meant metaphorically. Turbayne seems to think this happened to Berkeley and his mechanist rivals. They set out to offer metaphors but ended up propounding theories; they lost track of their own “as ifs” and became victims of their own insights.