[ QUOTE ]
In that sentence, are you using "predictions about the world" as a synonym for "statements of any kind," or as a synonym for "testable predictions."

If you mean "statements of any kind," then the theories are identical -- in which case we don't have two theories, but one (making your claim a tautology).

If you mean "testable predictions," then I will disagree and say that, for meta-evidential reasons, "the earth goes around the sun" is more likely to be true than "the earth goes around the sund because it is being pushed by invisible angels" even though the two "theories" make all the same testable predictions.

[/ QUOTE ]

I don't think that's what he's saying (not that I'm too clear on it by any stretch), but I think it's basically that if there are two (non-identical) statements about something having nothing to do with the empirical world, then there's no evidence that can be offered for or against either.

E.g.: T1: In heaven all houses are yellow
T2: In heaven all houses are green.

Well then, yeah, I guess he's logically correct that there isn't any evidence that is relevant, but that's because "evidence" connotes an observable fact and his "theories" expressly provide that they have nothing to do with the observable world.

So it's a logically valid, I suppose, it's just meaningless and unhelpful.