> That's the sort of rhetoric that lets Creationists claim that Natural Selection is just an opinion.

That's silly and offensive bullshit.  Creationists claim things all the time regardless of what anyone "lets" them do, but any Creationist who claims that Natural Selection is an opinion or hypothesis is full of crap.  Go study some Philosophy of Science, to understand what these terms mean.

And your whole approach here is dishonest; you know as well as I do that what Creationists claim is that "evolution is just a theory".  The problem with that claim is that they mistakenly equate the scientific concept of "theory" with the vernacular use, which is equivalent to "hypothesis".  It is precisely because hypotheses are not scientifically established claims that Creationists get leverage out of this semantic confusion.

> There is a difference between an hypothesis reached on the basis of evidence and a "mere opinion".

As noted in http://en.wikipedia.org/wiki/Hypothesis
"a hypothesis is a provisional idea whose merit is to be evaluated"

Both hypotheses and opinions are usually reached on the basis of evidence -- like my opinion that you don't know much about scientific method, derived from the evidence of what you have written.  It is your rhetoric, that confuses hypotheses with principles, laws, and theories, that provides the Creationists fodder.  Hypotheses are guesses -- they are actually even weaker than opinions, because good scientists don't hold a belief as to whether a hypothesis is true or false.  The only rule is that a hypothesis should be consistent with the known facts -- a rule that applies, or should apply, to opinions as well.  Basically, an opinion is a hypothesis that someone believes.  So some psycholinguist might be of the opinion that Bush has brain damage due to fetal alcohol syndrome, based on hsr knowledge of language, psychology, brain function, Bush's behavior, and that Barbara Bush is a lush.  But it's still an opinion, not a scientific conclusion.

> I was wondering whether a psycholinguist--who has studied the empirical evidence about how the brain influences how we speak--would have a hypothesis on what is wrong with Bush.

And my point was and is that any such hypothesis has no scientific validity, it does not serve as an authoritative claim, it cannot serve as a conclusion -- it's "a provisional idea whose merit is to be evaluated".  Any psycholinguist who testified that s/he had a hypothesis that Bush's speech was caused by drug or alcohol use would be laughed out of court.  An hypothesis is just a supposition as to what might be the case -- it's a starting point for an investigation.  What the psycholinguist would need is convincing empirical support for the hypothesis, and any psycholinguist who claims to have that is a quack.

I suggest that you read
http://en.wikipedia.org/wiki/Scientific_method

You'll get a lot more out of that than from wasting your time trying to shoot me down or to foolishly and offensively make me out as an enabler of Creationists.  I've spent plenty of time at talk.origins and elsewhere debating Creationists, and I'm quite familiar with their arguments and the flaws in them.