# Short Lecture About Science For Marc Colten Yesterday I tried to answer a posting in the '

```

Short Lecture About Science For Marc Colten

Organization: FB Physik, Universitaet Kaiserslautern, Germany
From: kring@physik.uni-kl.de (Thomas Kettenring)
Message-ID: <1993Jun28.205918.5092@rhrk.uni-kl.de>
Newsgroups: sci.skeptic

Yesterday I tried to answer a posting in the "CSICOP; origins and
problems with" thread, but the news server refused to do anything.
Now the discussion has gone further, in a sense, and my posting
is sort of obsolete.  I'll cut it down to what I find necessary
and post it after this.

But it looks like Marc still has not read about null hypotheses,
so here goes:
-----------------------
A null hypothesis is a hypothesis that a certain quantity has the value
zero.  If we know nothing of the quantity, we assume the null hypothesis
until it is proven that the value is different from zero.

It is easy to see that a null hypothesis can be disproven but not
proven.  We can't prove the value is zero, we can only say "it's very
close to zero, it's less than so-and-so."  But we can say "it's more
than so-and-so, it can't be zero."

Several cases were discussed here:

- Flatness of the earth:  The quantity is the curvature of the Earth
(the inverse of the Earth radius).  We assume it is zero (that is,
"the Earth is flat") until it is proven to be different from zero
(that is, we observe something that can't be observed when the
Earth is flat).
- Continental Drift:  The quantity is the velocity of two continents
in respect to each other.  We assume it is zero (that is, "the
continents don't move") until it is proven to be different from zero
(that is, we observe something that can't be observed when the
continents don't move).
- Telepathy and Co:  The quantity is the size of the effect of
telepathy.  We assume it is zero (that is, "there is no such thing")
until it is proven to be different from zero (that is, we observe
a telepathic effect).
- Flying Reindeer:  The quantity is the number of reindeer on Earth
capable of flying.  We assume it is zero (that is, "there is no such
thing") until it is proven to be different from zero (that is, we
observe flying reindeer).

("Observe" includes scientific rigor in all cases above, of course.
Stories of flying reindeer or jigsaw with continents don't count.)

You may ask, "why do we need a default?  Can't we wait until we have
enough proof either way?"  But as I said above, we can never have
enough proof for a null hypothesis, so if the null hypothesis is
true, you will for ever stay in the I-don't-know state.  Even if
it isn't you'll have no answer for a while.  So this method,
the method of the donkey that can't decide which of two haystacks
to eat and therefore starves to death, is utterly useless.

But if we haven't been able yet to disprove the null hypothesis,
that means that for all practical purposes the quantity in question
is zero, or so close to it that the difference doesn't matter yet.
So the null hypothesis is a good working hypothesis.  As soon as
it doesn't work anymore, you can toss it.

You may ask, "why don't we use a hypothesis close to the NH,
instead of the NH itself?  For example, we have very few telepathic
persons around, they can do it only part of the time?"  Occam's
razor is the answer.  "Don't unnecessarily multiply entities."
If you don't need the telepathy hypothesis to explain the world,
don't use it.  The NH is always simpler and therefore better, if
compatible with the data of course.
-----------------------
And another one about openmindedness with respect to new theories:
-----------------------
You seem to think (correct me if I am wrong) that there is one
correct way to behave for a scientist when hearing of a new
thought; a sort of middle-way skeptical openmindedness.  But if
you do indeed think that way, you are demandingo much from
scientists.

The scientific community consists of humans.  Don't you understand
that after I have examined the thirtieth perpetuum mobile and
found that it doesn't work, as the others didn't before, I get
slightly annoyed and don't want to have anything to do with it?
There are other things to do that are more promising.

Now that doesn't mean that nobody will listen to people who think
they have found something new.  A small percentage of scientists
will spend time for things others (or even they themselves) find
rather hopeless, either for the outside chance that there may be
some truth there, or out of a sense of duty to the search for
truth.

*One scientist alone can't do science.*  It's the whole of them
who do it.  You need others to examine your work, to test it
and look for mistakes.  But one specific scientist is not
obliged to test any specific thing; they can do what they want.
If you have built a perpetuum mobile and find nobody who wants
to test it, you can't blame them for not thinking it worthwhile.
Give them a real reason to do it; general statements about
narrow-minded dogmatists won't help.

Returning to "the correct way a scientist has to think":
It is needed that there is a diversity of opinions in the
scientific community.  The community as a whole has to be
open to new ideas, not single scientists.  Bringing everybody
on line won't help; it will make science monolithic.

There has to be "memetic diversity", so to speak; lots of
different ideas.  But there also has to be selection.  Bad ideas
aren't popular.  If you want to decrease the size of that
selection by demanding that everybody gets real open-minded,
you are hindering science.  Everybody will suddenly test
perpetua mobilia, and the people who build them will be
encouraged and make more of them.  (Of course they will claim
conspiracies too, as their true genius still isn't recognized.)

We have to decide between the Skeptic Skylla who now and then
devours someone who has found something real but has not enough
evidence yet (i.e. Wegener) and the Charlatan-Charitable
Charybdis which sinks the whole ship of science.

Some wheat will always land in the chaff, unless you don't
separate the two.
-----------------------

thomas kettenring, 3 dan, kaiserslautern, germany
I am the most humble person in the world.

```

E-Mail Fredric L. Rice / The Skeptic Tank