Moho: “If anything, the bumper sticker asks people to examine their own prejudices in light of the comment.”
No!
The bumper sticker only informs an anonymous person in the vehicle behind that the driver ahead of them does not share the prejudices they have. Nowhere in this phrase does the driver admit that she is also prejudiced.
You can’t invent a different meaning for this simple language, it speaks for itself. If in your world view everyone is prejudiced, you are forced to admit that you believe the driver is too. Then we both must surely agree that she is the only one on the road who is also a hypocrite in addition to being herself prejudiced, for pointing out that in others which she does not admit in herself.
Why else would someone put such a sticker on their car?
I do have one prejudice, and it’s acquired over years of experience. Whenever I detect that someone is a liberal, I presume that they are also quite stupid. That’s not always true, but it is far more often than not. Hence the prejudice.





