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Article 3025 of comp.ai.philosophy:
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>From: dlyndes@gothamcity.jsc.nasa.gov (David Lyndes)
Newsgroups: comp.ai.philosophy
Subject: Re: Cargo Cult Science
Message-ID: <1992Jan22.212846.24969@aio.jsc.nasa.gov>
Date: 22 Jan 1992 21:28:46 GMT
References: <92Jan15.081805est.14473@neat.cs.toronto.edu> <6030@skye.ed.ac.uk> <1992Jan21.182930.8953@aio.jsc.nasa.gov> <1992Jan22.183906.24919@gpu.utcs.utoronto.ca>
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Organization: Barrios Technology @ NASA/JSC; Houston
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In article <1992Jan22.183906.24919@gpu.utcs.utoronto.ca>, pindor@gpu.utcs.utoronto.ca (Andrzej Pindor) writes:
|> In article <1992Jan21.182930.8953@aio.jsc.nasa.gov>
|> dlyndes@deltahp.jsc.nasa.gov writes:
|> >
|> >   A) A theory such as F = k m1 m2 / r^2 makes NO predictions whatsoever.
|>  
|> Really? How about this: If a mass is twice as big the gravitational force will
|> be twice as big .

That is not a prediction, it is a conditional: "if P then Q".

|>                    Or: the gravitational force decreases with the square of
|> the distance .

This is a ratio.
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The concept of what counts as an observational consequence should not be this
difficult to grasp.  An example of an observable consequence of gravitation
would refer to the particular places and motions of particular bodies.  Let's
look at a simple example.

THEORY:                 F = k m1 m2 / r^2
THEORY:                 F = ma
THEORY:                 dx = a/dt

AUX HYPOTHESIS 1:       An asteroid "Hi-dee-ho" weighs 1000 pounds
AUX HYPOTHESIS 2:       A neighboring asteroid "T31" weighs 1000 pounds
AUX HYPOTHESIS 3:       At noon, we observe these two to be stationary
                        with respect to each other.
AUX HYPOTHESIS 4:       At noon, they were 100 miles apart.

SIMPLIFYING ASSUMPTION: Nothing else affects the motion of these two asteroids.

Calculations:

     The force on each asteroid is F = k * 1,000,000 / r^2.
     Since F = ma, the acceleration of each is k * 1,000/r^2.
     [...]
     [more calculations, we all did this in Physics 101]
     [...]
     Thus "Hi-dee-ho" and "T31" will be 5.3 miles apart at 1:00 P.M.

Observation:

     "Well, it's almost 1:00 now.  Lets take a look ... .  Rats!, they
      are 5.7 miles apart."

What do we do now?  Scrap one of the theories?  Nope!  We try to find
out what was wrong with our simplifying assumptions.

Prof: "Oops!  There is another asteroid weighing 500 lbs at coordinate
      <500,225>.  Lets add that to our auxiliary hypotheses."

Stud: "But Professor! That's not fair!  We justed refuted the theory!"

Prof: "Shut up kid, and do the calculations."

I'm on the professor's side.
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|>                 Aren't these verifiable (refutable) predictions?

No, they are not.

In the first place, it is not the verifiability or refutability of predictions
that concern us.  It is the verifiability or refutability of theories.  I
should assume though, that "predictions" was a slip of the tongue/keyboard.

In the second place, please attend to my argument!  It should be easy to
spot how to defeat my argument!  Show how you can "pin down" the auxiliary
hypotheses so that the theory MUST be the culpret.

The refutationists claim that the logical form of a prediction is:

            T -> O.

I claim that it is:

            (T & A) -> O.

Refutationists claim that from

            T -> O,       and
            -O
We conclude -T.

And so we can.  It is a form of deductive inference called "modus tollens".
But if the logical form of a prediction is not T -> O, then the refutationists
have shown nothing about how contrary observations work in science.  In
particular if the logical form of a prediction is T & A -> O,  then from:

                        T & A -> O    and
                        -O
We can only conclude    -T or -A.
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|> >
|> >   A) A theory such as F = k m1 m2 / r^2 makes NO predictions whatsoever.
|>
|> Rest of the posting is based on 'logic' similiar to the statement A)

Oh, really?  "A" is a bald claim not "based on logic" at all.  I took it
as so obvious that I didn't feel the need to justify it.  I was wrong to
think that way.  It turns out that you (and possibly others) don't know
the difference between an observable consequence and a ratio.  I hope
the above clarifies this distinction and thus makes "A" a bit more
intuitively obvious (or at least not appear trivially false).
-- 
+-------------------------------------+---------------------------------------+
| David K. Lyndes                     | "In 50 years, if we're nice to them,  |
| Barrios Technology                  |  computers will keep us around as     |
| email: dlyndes@deltahp.jsc.nasa.gov |  pets." --anon.                       |
+-------------------------------------+---------------------------------------+
| The opinions expressed are not necessarily those of my employer nor of God. |
+-----------------------------------------------------------------------------+


