Re: student debates on pseudoscience

["John S. Denker" <jsd@MONMOUTH.COM>]

Ben Crowell wrote:

> I'm teaching a conceptual physics course at a
> community college, and would like to have my students
> debate each other on issues related to pseudoscience.

There's a time and place for everything...
This exercise belongs in law school or maybe
drama school, not in physics class.

Lawyers admire a lawyer who can argue one side
of an issue on Monday and argue the other side
on Tuesday and win the argument both times, just
by force of argument.

Among non-lawyers, this engenders not admiration
but loathing.  And even within the legal system,
there are limits:  a lawyer may not cause or even
permit the introduction of misleading evidence.
(Bill Clinton was fined and disbarred for this.)

You can imagine some sort of continuum with physics
over near one edge and the typical debating society
over near the opposite edge.  It is often possible
to win a physics argument just by force of argument,
even if you've unintentionally got the facts wrong --
but if you do this, your colleagues will figure it
out sooner or later (probably sooner) and you'll lose
credibility.  Physicists have a long memory and no
sense of humor about such matters.  If you get
caught _intentionally_ distorting or concealing
the facts, you'll be shunned.

==============

How on earth would you propose to grade a debate
about pseudoscience?  Suppose a student comes up
with an intricate argument in favor of, say,
homeopathy....  Does he get high marks for skillful
argumentation, or low marks for not recognizing
how unscientific the argument is?

> For instance, I could ask
> one student to present the "pro" side on astrology,
> and another to take the "anti." The "anti" student
> doesn't prepare, does a lousy job, and the class then
> votes that astrology is a real science.

1) In law school, they symmetrize the situation by
assigning each student the opposite side of the
argument the following week.

2) I say again, not even lawyers are expected or
allowed to change the facts by arguing.  Debate
has its place, for example in policy issues, where
(typically) either option is viable, but one or
the other must be chosen, and the debate performs
what physicists call "spontaneous symmetry breaking"
by building a consensus around one option or the
other.  Debating factual issues (as opposed to
policy issues) is just totally a Bad Idea.

> So far, what I'm thinking is this:
> - No votes. The whole idea is silly anyway, since
> science isn't a matter of majority rule.

Right.