http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0016782

Here's a fascinating paper by Lera Boroditsky about how subtle metaphors influence the way we think about situations. Iirc, participants were asked to read a sentence about crime; in some versions, crime was described as a "virus", and in others crime was described as a "beast". People were then asked how they would stop the crime; the people who heard the different metaphors responded in different ways, but they were not conscious of how much the metaphor had influenced their response.