The infamous proof by handwaving is a revered practice in academic departments worldwide. While it is best deployed in the so-called "hard sciences", i.e. technical subjects, of mathematics, physics, and computer science, it is not without application in ’pataphysics, para-psychology, comparative and analytic literature studies, or sociology. The proof by handwaving, although wide-reaching in its application, is NOT a sturdy indefensible, and the wise will utilize it only rarely.
A few caveats:
- A chalkboard or whiteboard is nearly essential to the successful proof by handwaving. An overhead projector does not allow for the amount of distracting movement necessary for a successful proof by handwaving. In informal or strained circumstances, a cocktail napkin might suffice.
- Under no circumstances attempt a proof by handwaving in front of an audience of engineers. The engineer thrives on their understanding of minutia, this is why they are the bane of the stage magician, and they are typically rather tenacious. If it is unavoidable that you must employ the proof by handwaving on an audience of engineers, it is recommended you first soften them up with a few pitchers of beer.
The proof by handwaving, in seven simple steps:
- Assure your command of the flow of the presentation. Allow no interruptions or questions, and make sure that attention is on what you are about to attempt to prove.
- At your chalkboard, or reasonable analogue, write the starting state of the problem. Do this quickly, without hesitation. If the field of study is not one in which equations are common, abstract the facsimile of an equation from the situation, or construct a diagram.
- Wave your non-writing hand around vacuously as you declare any constants or variables. In these declarations, make great assumptions about the level of understanding in the audience. Note the salient point, but nothing more. Key phrases include:
- "Now, since … "
- "As we know, … "
- "Naturally, one finds … "
- Attempt to impart as little information as possible; eschew elucidation; admit nothing. A thick foreign accent or an incomprehensible mumble may be helpful, although sheer enthusiasm may suffice. Similarly, copious indecipherable notes or marks against what is already written will obscure and divert specific attentions.
- Cycle through these steps two or three times. Each time, re-write the equation making the obvious next step or add subsidiary equations that may or may not provide support or distraction.
- Right before the crucial leap of logic that will enlighten the audience with your brilliant solution or results, stop dictating your own writing to the board. Wave both hands around, but do not flail as you point at various areas of the board. Best effect is achieved if you make strong gestures to your left (the audience’s right), standing from a position to the left of the board, although in some instances, standing directly in front of a particularly gratuitous progression is advised.
- Now, clearly state the solution, you may wish to preface it with "therefore", or if you prefer, epilogue with "que-ee-dee". Then walk to a seat with deliberation. Take no questions.
Anecdotal evidence seems to support the theory that the proof by handwaving is most successful when the presenter possesses, or is believed to possess, or is paid to pretend to possess, expert knowledge of the topic. This power disparity between the presenter and the audience may hold the means by which to rate the effectiveness of any given attempt at proof by handwaving.
The proof by handwaving differs from discursive handwaving in that it is a distraction, a little act of magic, used disingenuously by the unprepared or charlatan. Facility in the employ of the proof by handwaving is not acheived through the practice of waving hands or tai chi push hands.