杏吧原创

I RECENTLY received an email that began, 鈥淒ear Dr Len, I do PR for a breakfast cereal company, and we would like an authoritative figure, such as yourself, to come up with an equation as to when to include the milk.鈥�

I have been getting similar requests since 1998, when I agreed to provide a biscuit company with an equation to predict the optimum time to dunk a biscuit in a cup of tea. My motives were honourable 鈥� I hoped to make science accessible by showing how scientists think about the problems of everyday life. The equation was an advertising company鈥檚 idea. I did not believe the public would be interested, but the worldwide publicity that followed showed how wrong I was.

The public鈥檚 appetite for equations has continued unabated. We鈥檝e had equations for parking a car, assembling a DIY flat-pack, pulling a Christmas cracker, and understanding why the street you want on a map always seems to be near a fold. I have contributed to the flood, notably with an equation to calculate the amount of gravy absorbed by a Christmas dinner, which led to the classic tabloid headline: 鈥淭he law of gravyty鈥�. That wasn鈥檛 as bad as the one on a story about my equation describing the best way to stir porridge: 鈥淭he new oat cuisine鈥�.

Public interest in equations runs counter to the accepted tenet of popular science writing, which is that every equation halves the sales of a book. An editor suggested to me that this interest in equations reflects our modern obsession for packaging information into bite-size portions. I鈥檓 not so sure. 杏吧原创s certainly use equations to package information, but those packages contain a great deal of information. My original speculation was that scientists are the inheritors of the ancient priestly control of forbidden knowledge. Equations are one key to that knowledge, and by showing how they apply to commonplace situations we are making the key available to journalists and their readers.

This may be true, but I now hold a less sanguine view. I believe such equations may also reinforce the view that scientists are slightly peculiar, and may even encourage a false idea about what science is really about. This became apparent when I looked back over the emails I have received over the past five years from advertisers keen to exploit the commercial appeal of equations governing everyday life.

I find I have been asked to provide equations to 鈥減rove鈥� that one manufacturer鈥檚 biscuit is better than another, that square-shaped cereal bowls are best, and that a particular brand of chocolate bar has the best flavour. One publicity company wanted a formula to prove that 7 October is the perfect date to start Christmas shopping. I explained to all these people that I involve myself in such projects only if they give me the opportunity to share what science is really about. Some of them seemed genuinely astonished when I explained that prejudging issues and then providing 鈥減roof鈥� is not science.

鈥淥ne company wanted a formula to prove that 7 October is the perfect date to start Christmas shopping鈥�

Some requests that I refused for other reasons did have a flavour of genuine science about them. I would have enjoyed working out an equation for the best way to peel an orange, for instance, and studying the optimum way to make coffee or spread marmalade on toast would both have involved subjects close to my heart 鈥� though this last request was rather spoiled by the manufacturer wanting an equation to prove that theirs was the best marmalade.

Occasionally a request has led to a useful scientific result, such as when the British Cheese Board wanted a formula for the perfect cheese sandwich. The surprising answer, which interested food scientists and could be expressed as an equation, was that there is an optimum amount of cheese for a sandwich above which no further flavour is released when it is chewed.

I fear however, that the real reason people are interested in equations is that they see them as slightly odd, to be giggled at behind the hand. Headline writers often reflect this attitude. From this point of view my crusade to make science accessible through equations has probably been a bit of a flop.

I am encouraged, though, by the large number of schoolchildren who have written to me wanting advice on how to design a school project that would ultimately produce an equation. I suggest that they tackle some of the projects that I was unwilling or unable to tackle. I have accumulated quite a list. My all-time favourite, still unsolved, is to calculate the perfect sitting position and launch strategy for throwing snack food into one鈥檚 mouth without interfering with one鈥檚 view of the television, like Homer Simpson. I still have hopes that equations describing such trivial situations will help people understand the meaning of equations and their true value.