Even the I Can't Believe It's Not Butter can't believe that it itself is not butter.
"I can't believe it's not I Can't Believe It's Not Butter!"
This is changes we can all believe in.
"Ohhh no, I can't believe I just ate all that food."(Please accept this as a tip, Ms. Waitress)
We had something going for a while, but I just couldn't make him believe that it was not butter.
I believe I can fly, I believe I can vandalize.