In the 1994 surprise hit Il Postino, the Chilean poet Pablo Neruda is shown impressing upon the town postman and aspiring poet, Mario, the importance of metaphor in poetry. Good poetry is impossible without clever metaphors, but for more mundane writing the device and its close relative, the analogy, are perhaps best dispensed with. For, more often than not, they seem to do more harm than good, when it comes explicating a concept, plan or analysis. Take the following confusions…

A race to the finish?

At the large corporation at which I work, an intelligently crafted presentation that I was witness to included nonetheless a strange use of metaphor: to stress the need for the company to react with agility and speed to the demands of the market, the presenter could have used those very terms (“agility and speed”) with sufficient markup or decoration, in his slide(s). Instead, perhaps for greater effect, he chose to use images to depict the difference between the company today and the one it need become to succeed in the future.

The unfortunate images he chose were those of an elephant (to represent the current lumbering giant of a corporation) and a cheetah (to suggest the corporation remake itself in the image of the fastest recorded land animal). This is unfortunate since his metaphors, rather than sealing his point, argue for quite the opposite considerations! For in the game of Darwinian survival, it is the resilient generalist, the elephant, that has won the race, while the over-specialised cheetah is near extinction (having sacrificed much evolutionary opportunity to achieve its impressive speed).

Sometimes, an analogy or metaphor may turn out to be quite dangerous!

A bitter cup of tea

Some of those opposing the current US administration’s ambitions and programmes have anointed themselves the “Tea Party” — in doing so they cleverly associate themselves with the founding of the nation, and its libertarian roots as they see it. This self-identification paints a picture of citizens struggling for individual rights against an overbearing government that is intent on collecting and putting to waste their hard-earned money. If their argument or association is valid, the analogy they employ is simple and evocative, just the sort of good purpose a metaphor can serve (on the other hand, if their underlying thesis is invalid, this highlights another danger of metaphors: that they can often mask the real issues and obtain agreement via emotional appeal; that danger is addressed in the next section).

In response, their detractors — the defenders of President Obama and the Democratic Party — have launched their own “party”, the “Coffee Party”. But unlike the shrewd label “Tea Party”, this one presents no ideological picture or emotional appeal to its members or the general public (that they wish to influence). If anything it reinforces the derisive image of liberals painted by their opponents, the image of effete coffeehouse pseudo-intellectuals.

A mountain out of a molehill

The mathematics and computer science world has been abuzz lately with the announcement of a proof that P ? NP (a very important unsettled question in computer science / complexity theory). Worry not if you are unaware of P, NP, etc., for they are not critical to the point to be made. The claim of a proof was made to a small number of mathematicians and computer scientists, but was rapidly disseminated through the research community, drawing comments from far and wide. Which led to the concern that should the proof turn out to be wrong (or worse frivolous), then the precious time of some very important mathematicians, who were pulled into the verification effort, would have been wasted irredeemably.

To help explain this loss of time, one of the commenters on a popular blog discussion of the proof offered the analogy of a hiker stranded on a mountaintop. The call for rescue, the analogy goes, results in serious mountain climbers “mount[ing] a brilliant coordinated effort … to get the hiker off the mountain”. The analogy purportedly helps us see how the lack of preparation, as well as other errors of the hiker have wasted valuable resources and time.

At first blush the analogy seems to convey in clear terms the terrible consequences of soliciting expert opinion without prior rigorous (and lengthy) individual effort. However, while the problem may be real, the analogy is in fact deeply flawed. As might be evident, the flaw here is that a call for rescue, imposes an ethical imperative that cannot be ignored, is hardly similar to a proof verification request which can be entirely ignored without guilt or treated with a level of importance of one’s choosing.

Metaphors and analogies are dangerous and misleading beasts. It is, I think, time for the surgeon general to opine on them and alert the public on the menace. Until (s)he does, I propose the following rules of usage:

1. Eschew the metaphor when words suffice. Metaphors should clarify or help the reader’s intuition grasp a complex concept in a simple way. If the concept itself can be expressed in a sentence or two, do you really need the metaphor?

2. Ensure your metaphor is “cashable” (as the philosopher Jerry Fodor writes). Given the metaphor, you (and the reader) should be able to produce the more complex paragraph or two that the metaphor aims to neatly summarise. If there is no underlying explication, the metaphor is mere hand-waving.

3. Tickle the brain, not the heart. Getting people to agree with you by appealing to their sentiments is not always cricket. Aim the metaphor not at imparting a good feeling but at clear thinking. Motivational metaphors are best left to the purveyors of inspirational doodads.

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