“Flawed” Analogies

Note: This post contains plagiarism: I’ve stolen some content from an earlier blog post, and from my comments on another. I beg the forgiveness of faithful and diligent readers.

Recently I’ve had to deal with some complaints from people on Twitter who seem to have misinterpreted certain analogies. Worse than that, sometimes it seems as though they don’t understand why and how we use analogies at all. Here are some examples.

I suggested, “Waiters don’t tell the chef when the food is ready to serve; why should testers tell the managers when the product is ready to ship.”

One fellow objected, claiming that waiters only deliver the food, and that to use that analogy diminishes the role of the tester. He implied that testers would be more like food-tasters who would inform the chef about the quality of the dish and possible problems with it. Fair enough—but even then, the chef would have responsibility for the decision to deliver the food.

Another fellow objected, demanding “Do you mean that testers aren’t first-class members of your dev team?” Well, as a matter of fact they are—but now I have some questions about whether this person might not see waiters as first-class citizens of a restaurant. As Milton said, “They also serve who only stand and wait.” (Yes, that’s a joke.)

Someone else objected when I said that “Testers are responsible for quality in the same way that investigative reporters are responsible for Supreme Court decisions.” The response was, “This surprises me. Don’t we try to get testers involved up front, w/lotsa communication & collaboration, to improve quality?” Yes, we do. The point here is simply that, whatever their activities, responsibilities, or contributions, testers are not responsible for making decisions about quality, but rather for informing decisions about quality. Like investigative reporters might inform the evidence presented in a court case, or in issues of social policy. That’s still a completely valuable role in a society, but it’s not the decision-making role that we would associate with those who make the laws or provide enforceable interpretations of them.

Analogy, metaphor and simile are kinds of associative language. Let’s start with “analogy”. The Oxford Dictionary of English (available as a killer app for the iPhone) calls analogy “a comparison between one thing and another, typically for the purpose of explanation or clarification…; a correspondence or partial similarity (my emphasis there)…; a thing that is comparable to something else in significant respects”.

The word comes from the Greek. “Logos” refers to words, thoughts, and reasoning. The prefix “ana-” denotes several possibilities, including “up, upward, throughout, backward, back, again, anew”. Analogy, therefore, suggests thinking something through, or reasoning back to some similarity, or looking at a thought again, or thinking something up. In other words.

For metaphor and simile, I’ll repeat here a quote from an earlier blog post: In his book The Educated Imagination (based on the Massey Lectures, a set of broadcasts he did for the Canadian Broadcasting Corporation in 1963), Northrop Frye said, “Outside literature, the main motive for writing is to describe this world. But literature itself uses language in a way which associates our minds with it. As soon as you use associative language, you begin using figures of speech. If you say, “this talk is dry and dull”, you’re using figures associating it with bread and breadknives. There are main kinds of association, analogy and identity, two things are like each other and two things that are each other (my emphasis –MB). One produces a figure of speech called the simile. The other produces a figure called metaphor.”

If it helps, think of an instance of associative language as a kind of model. Models are heuristic representations—literally, re-presentations—of something complex in terms of something simpler; of something unfamiliar in terms something more familiar; of something more abstract in terms of something more concrete. “Heuristic” is a key adjective here, suggesting that models help us to learn, and are fallible. As Nassim Nicholas Taleb says in The Black Swan, “Models and constructions, these intellectual maps of reality, are not wrong; they’re wrong only in some specific applications.” Absolutely true—and you can flip it around to say that models are right only in some specific applications too. It is their very imperfection—the fact that they do not represent the thing being modeled in every dimension—that makes models useful and powerful. The relative simplicity of the model is an aid to our understanding of a more complex subject. The purpose of models and associative speech is not to create an exact parallel, but to get people thinking in terms of similarities and differences. Were there a one-to-one correspondence between every aspect of a model and the thing being modeled, there would be no simplification and no point in using the model. It would be like Steven Wright’s full scale map of the United States: “It took me all last summer to fold it.”

Metaphor and simile trigger the capacity of the human mind to forge new links between ideas. Frye again: “The poet, however, uses these two crude, primitive, archaic forms of thought in the most uninhibited way, because his job is not to describe nature but to show you a world completely absorbed and possessed by the human mind… The motive for metaphor, according to Wallace Stevens, is a desire to associate, and finally to identify, the human mind with what goes on outside it, because the only genuine joy you can have is in those rare moments when you feel that although we may know in part, as Paul says, we are also a part of what we know.”

If I were to tell you that my dog were like my car in that they both require a lot of maintenance, would you expect my dog to have a gas tank? Would you expect me to take the dog to my mechanic when it appeared ill? If I said that picking up the guitar again after a couple of years was “riding a bike” for me, would you take me literally and envision a musical instrument with wheels and handlebars? If I were to suggest that my former boss was a pain in the ass, would you expect everyone at work to have trouble sitting down? If I said that a friend is as honest as the day is long, would you think that I measured honesty in hours? If I said that your newer testers were green, would you contradict me because they didn’t match a certain Pantone colour?

Analogies are always flawed by design. They’re intended to make people think about the ways in which something is like something else, while intentionally ignoring the ways in which they’re different. That is, they’re not supposed to be perfect. They’re supposed to draw attention to some factor of something, so that people can consider that factor, and possibly others, in a new or different light. Notice that I can use that expression, “in a new or different light”, and you don’t get confused or think “Hmmm…incandescent or fluourescent?”

Complaining that an analogy is flawed is like complaining that a model airplane (say, one designed for a wind tunnel) is flawed because it’s not big enough to carry real passengers. Confusing an analogy with a fact in this way is a symptom of model blindness, evidence of a failure to distinguish between models and reality. That can bite people in two ways: first, by limiting our imagination to the literal, rendering us capable of less powerful reason, and even making us something less than human (which is what Frye warns against); and second, by allowing us to place too much trust in our models, making us vulnerable to risk when then model doesn’t apply (which is what Taleb warns against).

Some people say that they don’t like analogy, or that they don’t use analogy. To me, that’s a symptom that they’re not paying attention to the way they speak and the way they think. If you’re such a person, I have a suggestion: try paying attention to the number of times per day you describe or envision something in terms of something else. Try monitoring how often you try to represent an idea with a sketch. Note each time you say, “That’s like…” Get a friend to observe each time you use a metaphor. You’ll shortly observe that we’re all using analogy, all the time. Then try quitting for a day, like fasting or giving up cigarettes for Lent. (Did you notice? Those were similes. Did you understand them and absorb them, or did you say, “I don’t smoke”?) Not only will your speech or writing be limited, but I would argue that your capacity to reason will be limited as well.

If you’re in software development, the program that you’re writing or testing is a way of modelling some task that the user wishes to perform. The ways we have of describing those programs are universally framed in terms of models, analogies, metaphor, and simile. We humans are analogy machines (Did you notice? That’s a metaphor.) So if you don’t like “flawed” analogies, it would nonetheless be a good idea to get used to them.

Postscript, 2013/12/10: “A study published in January in PLOS ONE examined how reading different metaphors—’crime is a virus’ and ‘crime is a beast’—affected participants’ reasoning when choosing solutions to a city’s crime problem…. (Researcher Paul) Thibodeau recommends giving more thought to the metaphors you use and hear, especially when the stakes are high. ‘Ask in what ways does this metaphor seem apt and in what ways does this metaphor mislead,’ he says. Our decisions may become sounder as a result.” Excerpted from Salon.

Another postscript, same day: have a look at Surfaces and Essences: Analogy as the Fuel and Fire of Thinking, by Douglas Hofstadter and Emmanuel Sander for a look at how pervasive and fundamental associative speech is.