You can not be Sirius!
Authors: Ken Dobson Honorary Editor  
Published: August 2002

As the astronomer said who pointed his telescope in the wrong direction. Physics is not famous for having a high joke-to-mass ratio, and the above attempt is the best I can do. But if we somewhat boringly deconstruct it we can see that to dredge out its minuscule humour content readers must supply some knowledge of their own, culled from basic astronomy and the behaviour of a notoriously short-tempered tennis player.

Many jokes are like that - they rely for their effect on the ability of the targeted amusee to collate previously acquired knowledge. Other types of joke present a confusing or puzzling accumulation of details which may be meaningless, even boring, until all is set right by the final denouement - the punch line.

[Reader: please insert your own joke here. If I could write jokes I'd be earning more money (some money) somewhere else.]

Ah! Now it all makes sense. The tension, skilfully built up by a skilled presenter, explodes in laughter, an expression of the sheer pleasure produced by understanding. Jokes of course don't work if the punch line comes first.

I wonder if Newton laughed when that apple hit him on the head, providing the punch that made simplifying sense of so much complexity. How many of our students laugh, or at least get some kind of pleasurable sensation, when presented with Newton's laws of motion, or the quantum theory explanation of the photoelectric effect? The great ideas in physics have as their main purpose the simplification, the making sense of, a set of puzzling or even contradictory phenomena. We should be able to get students to smile, at least, now and again. Good teachers know this, of course, and do not begin a course, let alone a lecture or demonstration, with a definition or a physical law. First come some interesting and intriguing phenomena - things are recalled, revealed or made to happen in front of our very eyes. What is puzzling or unexpected is skilfully drawn to our attention. We are encouraged to make guesses at the solutions, to anticipate the punch line. The very skilled elicit incorrect predictions and arrange, poker-faced, for them to be demolished by a demonstration of phenomena, in real time. Even so they might not, of course, reach the hilarious heights of the carefully rehearsed, disastrous outcomes of the comedian-conjuror Tommy 'Just like that!' Cooper, fondly remembered by older (and British) readers. Some of us, though, may have produced similar outcomes by incompetence or accident.

But when students do get it right the pleasure is obvious, and they are even more pleased to be given the official more carefully or elegantly phrased denouement - enjoying the fact that the 'knot' has been successfully untied**. Is this how you, dear reader, present physics to your students? Or should you spend more time watching comedians on TV? Maybe INSET funds could be provided for courses run by experts in the field. Or do you start a topic with the definitions? Or do your students start an investigation by writing down the only possible prediction, based on carefully taught prior knowledge as required by the national education system, so that the outcome is only a surprise as a result of Cooperian ham-fistedness? Certainly it is rare for scientific papers to deviate from the conclusion-first-argument-later mode, and examination questions tend to be even more traditional. Most still have the structure definition, experiment to prove...or measure..., well-rehearsed computation.

But examinations aren't supposed to be funny. Now here's a thought. Suppose we got them all into the examination hall and told a joke, whose punch line only made sense if they knew the physics? Only those who laughed would be credited with the mark. Cheaters would of course be detected by occasionally inserting jokes that were only funny if the physics was wrong. There is doubtless a ready supply of constructivist theorists of learning who could supply the material. The whole thing could be done using television, with the funniest available physicist as presenter. The vast sums of money now expended on GCSE could be saved and used to buy textbooks or even pay teachers more.

**...untied
Ex Latin dis - nodare (via old French), 'nodare' meaning 'to tie a knot'.