[net.misc] Wanted: list of proof methodologies

marks@Cascade.ARPA (11/09/85)

--

I'm looking for a list of humorous proofs I once saw.  It included such
proofs as:

    Proof by lack of counterexamples:
	"I looked for a long time for counterexamples, and I couldn't
	find any, so it must be true."

    Proof by authority:
	"I asked Knuth and he said it was true."

    Proof by blatant assertion:
	"This is obvious to anyone who looks at it."

    Proof by intimidation:
	"I'm your thesis advisor, so it must be true."

... and so forth.

Does anybody have a complete list of such "proofs" that you might be
able to send to me?

Thanks!

Stuart
-- 
Stuart Marks, Center for Integrated Systems, Stanford University
    {ucbvax,decvax}!decwrl!glacier!marks, marks@su-cascade.ARPA

"Is not Napoleon.  Is not Hitler.  Is not Mussolini.  Is Allegro con Brio!"
		-- Toscanini, on Beethoven's 3rd Symphony, "Eroica"

chabot@miles.DEC (11/12/85)

A book you should check out is _How_to_Solve_It_ by Polya.  I'm pretty sure it's
still in print.  Besides being a wonderful book, it has a few gems about
math professors, differential equations, and other incidents in learning math.

When I was a frosh, I heard in 18.01 lecture a professor admit to "Proof by
Erasure".  This only works for blackboard discussions--as you cover the board
you erase the questionable parts.

kort@hounx.UUCP (B.KORT) (11/14/85)

Try some of the books by Raymond Smullyan.  The one
entitled, "What is the Name of This Book?" has some
amusing proofs in it.  In fact, I recommend all of
Professor Smullyan's books, no matter what topic
you're interested in.  He seems to have refreshing
answers to every question that comes to mind.

zwicky@osu-eddie.UUCP (Elizabeth D. Zwicky) (11/15/85)

In article <21@Cascade.ARPA> marks@Cascade.ARPA writes:
>I'm looking for a list of humorous proofs I once saw.  It included such
>proofs as:
>
>    Proof by lack of counterexamples:
>	"I looked for a long time for counterexamples, and I couldn't
>	find any, so it must be true."
>Stuart
>-- 
>Stuart Marks, Center for Integrated Systems, Stanford University

	Try the book _A Random Walk through Science_, which
also contains many other gems, including a stress analysis
of a strapless evening gown, and how mathematicians catch lions.

The Quantum Physiscist's method:

Place a cage in the middle of the desert. At any moment there is a
finite probability that there is a lion in the cage. Wait.

	-Elizabeth D. Zwicky

mopa@ur-tut.UUCP (Mike Opacity) (11/16/85)

I remember reading this in a column by Ed Zern a few years ago:

How to cage a lion:

step 1) get a reasonable size cage.
     2) Place the cage somewhere.
     3) get into the cage.
     4) perform a simple inversion and the lion is caged.

-- 
Mike Opacity 
UUCP:    {allegra,seismo,decvax}!rochester!ur-tut!mopa
BITNET:  mopa@uorvm
USNAIL:  PO 28355 River Station, Rochester NY 14627