Respectable Opinions

Opinions are easy to get -- an old military adage about opinions noting, in part, that everyone has one -- but many of them aren't particularly valuable or useful.

So how do you separate the occasional grain from the clouds of chaff?

This is most commonly a matter of the authority, status or position of the person whose opinion is at issue.  The opinion of a respected radiologist as to the value of mammography should have a pretty high level of credibility, the opinion of an anonymous responder to a blog should not.  This is not a matter of class prejudice, it's a matter of knowledge -- of the person's prior assessment of facts and assumptions relating to the specific subject.

Now, if the radiologist offers an opinion about how individuals obtain health insurance to pay for mammogram, that's a different story.  Knowledge about the medical issues does not confer special command over the financial, legal or social issues associated with insurance.

In fact, if the radiologist gets going too much on such issues unrelated to the medical basis of his or her expertise, you may well start having questions as to whether opinions on the medical issues are being distorted to conform to these other issues.

And if the radiologist turns out to have integrity issues -- making spurious claims based on weak statistical analysis of doctored data -- then his or her opinion deserves no more credibility than the hack blogger.

If authority is to be accepted as a substitute for a detailed presentation of facts and assumptions, it has to be built on a solid foundation of trustworthiness, which is the most fundamental of all human virtues...