# "How to prove it" joke

Proof by example:
The author gives only the case n = 2 and suggests that it contains most of the ideas of the general Proof.
Proof by intimidation:
"Trivial."
Proof by vigorous handwaving:
Works well in a classroom or seminar setting.
Proof by cumbersome notation:
Best done with access to at least four alphabets and special symbols.
Proof by exhaustion:
An issue or two of a journal devoted to your Proof is useful.
Proof by omission:
'The reader may easily supply the details'
"The other 253 cases are analogous"
"..."
Proof by obfuscation:
A long plotless sequence of true and/or meaningless syntactically related statements.
Proof by wishful citation:
The author cites the negation, converse, or generalization of a theorem from the literature to support his claims.
Proof by funding:
How could three different government agencies be wrong?
Proof by eminent authority:
"I saw Karp in the elevator and he said it was probably NP-complete."
Proof by personal communication:
"Eight-dimensional colored cycle stripping is NP-complete [Karp, personal communication]."
Proof by reduction to the wrong problem:
"To see that infinite-dimensional colored cycle stripping is decidable, we reduce it to the halting problem."
Proof by reference to inaccessible literature:
The author cites a simple corollary of a theorem to be found in a privately circulated memoir of the Slovenian Philological Society, 1883.
Proof by importance:
A large body of useful consequences all follow from the proposition in question.
Proof by accumulated evidence:
Long and diligent search has not revealed a counterexample.
Proof by cosmology:
The negation of the proposition is unimaginable or meaningless. Popular for Proofs of the existence of God.
Proof by mutual reference:
In reference A, Theorem 5 is said to follow from Theorem 3 in reference B, which is shown to follow from Corollary 6.2 in reference C, which is an easy consequence of Theorem 5 in reference A.
Proof by metaProof:
A method is given to construct the desired Proof. The correctness of the method is proved by any of these techniques.
Proof by picture:
A more convincing form of Proof by example. Combines well with Proof by omission.
Proof by vehement assertion:
It is useful to have some kind of authority relation to the audience.
Proof by ghost reference:
Nothing even remotely resembling the cited theorem appears in the reference given.
Proof by forward reference:
Reference is usually to a forthcoming paper of the author, which is often not as forthcoming as at first.
Proof by semantic shift:
Some of the standard but inconvenient definitions are changed for the statement of the result.
Proof by appeal to intuition:
Cloud-shaped drawings frequently help here.

## Blonde and Genie

A blonde, a brunette and a redhead were stuck on an island for many, many years until one day they found a magic lamp. They rubbed it hard and out popped a genie. He said that he could only give three wishes so since there were three girls, each would get one wish. The redhead more...

## Santa Riddle

Why is santa claus always so happy?
He knows where all of the bad girls live!

## Gas in the restaurant

by Funny J

I was in the restaurant yesterday when I suddenly realized I desperately
needed to pass gas. The music was really, really loud, so I timed my
gas with the beat of the music.

After a couple of songs, I started to feel better. I finished my coffee,
and more...

## Knock knock... cows

Person 1: Knock, Knock
Person 2: Who's there?
Person 1: Cows go.
Person 2: Cows go who?
Person 1: No, silly! Cows go moo!