From: schwae@aix.rpi.edu (Eric A. Schwartz)
Subject: Re: Vegetarian diets
Organization: Rensselaer Polytechnic Institute, Troy, NY
Distribution: usa
Date: Sun, 11 Oct 1992 02:44:08 GMT

In article <1992Oct9.170731.7750@netcom.com> strnlght@netcom.com (David Sternlight) writes:
>
>Eric A. Schwartz posts an anti-vegetarian message so lacking in logic
>that one is tempted to ascribe brain-damage to a meat diet.
>
>In response to a comment that meat and dairy lack fibre, he suggests
>why not eat polythene. Yes, and if my grandmother had baytzim she'd
>have been my grandfather. The total irrelevance of such a comment is
>blatant. One need not eat bad things to get fibre; vegetables will do
>very well.

Fiber is a bad thing?  Polyethylene is not a bad thing, just another
thing that you currently don't eat.  It is a far more effective
source of fiber than even pure bran, and the one instance I know
of where it was actually fed to people, it was rated as far more
palatable than other sources of fiber offered.  I wouldn't actually
recommend a polyethylene substitute, since it is indigestible, and
could become an ecological problem as it entered the waste stream.
 
>He then introduces a mad syllogysm as follows:
>1. 5% of deaths are of vegetarians.
>2. Most vegetarians are young.
>3. Therefore well over 5% of vegetarians die young.
>
>The logical flaws in the above take the breath away.
>
As did the flaws in the original statistics.  You didn't
question them, I notice.  See if you follow this:

Only 5% of American deaths are vegetarians.  This statistic was a 
given.  The conclusion drawn was that meat eaters were nearly 20 times
as likely to die at any given moment.  Faulty for a number of reasons.
First, the actual conclusion that can be drawn reliably from such data
is that if you come upon a corpse, you could lay 19:1 odds that it 
is (was) a meat eater.  Second, it neglects to provide any reference
framework.  If 50% of Americans are vegetarians, and only 5% of dead
ones are, then that is a big deal.  However, if .001% are vegetarians,
then they are hugely overrepresented in terms of number of deaths.
Then, if you bring in the other statement made, that most vegetarians
are under 40, that weights the expected number of dead much lower.
Assuming 5% vegetarians, 5% dead vegetarians would be expected if
vegetarianism had no influence.  However, if they are mostly young,
then maybe 1% deaths would be expected.  So 5% would indicate that
veges are far more likely to die at any given time.  

To put it another way, if vegetarianism were healthy, the the vast
proportion of vegetarian deaths would be older.  Since most vegetarians
are young (to be generous, lets say most=51%), that raises considerably
the needed number of vegetarians to fill the death quota.  In order for
5% deaths to support that contention, vegetarians would have to make
up 10.2% of the population.  If most = 80%, the needed number of
vegetarians would be 1/4 of the total population.  And of course, all
this presumes that the other 95% are young carnivores.  If the other
95% are old carnivores, then it is meaningless, since it just serves to
support the contention that old people are more likely to die than
young ones.

Yes, my statistics called for a considerable number of unsubstantiated
assumptions.  My point is that the conclusion presented before called
for an equal number of equally unsubstantiated assumptions.  My 
duplication of that error is called "sarcasm" or "satire".

E.S.
Newsgroups: sci.med.nutrition