[extropy-chat] Appeal to Authority

[Hal Finney]

Another problem with appeal to authority is relatively obvious: how do you
know you've got a good authority?  I've run into this problem myself as
I try to understand what the scientific consensus is on various matters.
It is easy to find people who will misstate the consensus for their
own ends.

Take a controversial issue like global warming.  You can find websites
which claim that the scientific consensus is that warming is not caused
by man and that it will have few or no harmful effects.  Other sites
claim exactly the opposite.  I do not mean here to open up debate on
this matter, merely to point out the difficulty the layman may have
in deciding where the genuine consensus lies.  Or consider the recent
discussion about the role of medicine in reducing mortality; again the
big issue (at least to me) was whether there is in fact a consensus
about this in the relevant expert community.

Even in the courtroom, where judges do try to vet experts and make
sure they are legitimate, it is common for each side to put on expert
witnesses who contradict each other.  In fact it is well known that
certain people specialize in being "experts for hire" for legal cases
and are willing to tailor their testimony to just what that side wants
to present.  So although the legal system does recognize and accept
appeals to authority in the form of the expert witness, in practice it
doesn't always work too well.

Hal