I wrote an essay on how "theory" is defined in the scientific sense and how it relates to evolution for my Freshman Composition 2 class. I uploaded it here: http://sharedreviews.com/article/more-than-a-theory-defining-scient...
Hope this helps.
No, they have not rebutted it. But it doesn't prove that evolution is true. It forces them to except that theories are valid beliefs not based in faith, it doesn't force them to accept that evolution is a theory.
Although, that puts them in a position of disagreeing with the entire scientific community, but that isn't abnormal.
It is probably better to avoid the issue altogether, and if your ability to defend evolution fails, just put it off the table, and point out that even without evolution, their position doesn't get any stronger.
Evolution is a theory that is widely accepted as fact. He is wrong to say two things: That we believe IN it, and that to believe it requires faith. First off, no one believes IN evolution, but only only believes that evolution is a scientific fact. Secondly, to believe it as a fact of science does not require any faith as we have tons of evidence to support it, between observation, fossil records, vestigial organs, radiometric dating of the fossils to propose when the ancestors existed and just basic extrapolation. He is trying to compare science to religion which is the same as comparing apples to oranges.