Fallacy of Minority Dissent

Wednesday I came across the following passage:

For example, it takes a certain level of hubris for a man to take a public stand on the threat of global warming when he has no background in the subject, and when the evidence for global warming is sketchy.

Now here's the thing:  William Fitzpatrick, who made that quote about the Pope, appears to have "no background in the subject", as he says of the Pope.  That means that for him to say that "the evidence for global warming is sketchy" requires him to believe that it is not necessary to be an expert to determine whether the science behind climate change is valid or plausible; a layman such as himself must be reasonably able to make that call.  If he makes that admission, though, it applies as much to Pope Francis as to William Fitzgerald.  This really is a case of Tu Quoque; it shows that Fitzgerald displays his own hubris, by his own standards, in making the charge of hubris against Pope Francis.  Of course that doesn't prove that Fitzgerald is wrong, only that he exercised poor judgment in choosing this particular argument.

In some of the defense of Fitzgerald in the comments underneath his post, though, one finds a fallacy that seems to be quite common these days.  Undoubtedly it has a proper name, but it doesn't quite fit into any of the categories I have run across.  It is related to the appeal to authority.  The essence of it is this:  If any expert can be found who dissents with the consensus on a subject of his expertise, that is sufficient to prove that there is a reasonable doubt about the consensus view. 

There are two basic problems with this.  The first is that not all people claiming to be "experts" have equal claim.  Just because someone is a commercial pilot does not mean he is a good pilot; sometimes a bad pilot falls through the cracks.  The same is true of engineers, scientists, doctors, NFL coaches, generals, CEO's -- pretty much every conceivable specialization.  That's true even if we are talking about specializations with high standards and relatively objective criteria.

The second problem is the basic cussedness of mankind.  By this I mean every kind of pigheadedness, from the desire to contradict a personal or professional rival to what Edgar Allan Poe called "The Imp of the Perverse".  This cussedness is probably the best explanation why no idea is too ridiculous to attract at least some believers.

As a result, it is impossible to say whether objections to a consensus by the relevant experts are plausible and valid without actually understanding both the reason for the consensus and the reason for the objection.