Irrelevance, The Fallacy of

(Ignoratio elenchi). The classic illustration of this fallacy is the case of a man who, on his way home at night, drops his keys. Instead of searching the area where he dropped them, he searches under a street light elsewhere, on the basis that searching is easier when well-lit. Ignoratio elenchi literally translates as “ignorance of the connection”—an elenchus in Rome was a pendant worn as an ear-ring: it joins up.I89

This is a core fallacy, in that many of the other fallacies can be seen as examples of it. Most arguments arise because one or both sides have missed the point. If, when you hear an argument about a matter of public policy, frustration builds up, and you say to yourself, or anyone else in earshot, “But the whole point is . . .”, that argument has probably been corrupted by the fallacy of Ignoratio elenchi.

We have a good example of this happening—and being detected—in John Maynard Keynes’ General Theory. In chapter 19 he is writing about the received view of his time that the way to take an economy out of recession is to keep wages low. That seems reasonable doesn’t it? Low wages feed through to low prices, and that means that consumers can afford to buy more, which in turn means that the sale of goods will go up and the economy will rise out of recession. Yes, yes, but the whole point is that if people are earning lower wages, their incomes will be lower too, so demand will fall, leading to a cycle in which low wages and low prices reinforce each other, so that the low wages will simply reduce prices, and an economy which is already stuck in recession will stay there.I90

If by some magic you could reduce wages without reducing demand, that of course would work fine. But, as Keynes points out . . .

. . . this assumption reduces the argument to an Ignoratio elenchi. [The classical theory on which it is based] has nothing to offer.I91

Sadly, the tendency to miss the point of an argument increases in proportion to the passion with which the arguer is committed to her case. For example, take the argument that every household should, by law, have in its possession one red widget. All sorts of reasons can be advanced for or against: this requirement is key to the government’s policy of health and fitness of young people; it is especially relevant to its healthy hearts programme, to the prevention of verrucas, and to the maintenance of a balanced diet; it is essential to the nation’s competitiveness and standing in the world, to equal opportunity and the maintenance of a level playing field; indeed, there is a target to achieve 80% household ownership of red widgets by 2020—a major challenge, but an achievable one within the context of the Europe-wide red widget policy which will play a critical role in the Union’s role as a world player, a counterweight to the United States and China; a global problem requires a global solution.I92

It is the passionate sincerity that keeps the hare of irrelevance running. If the discussion were merely technical—whether red widgets work best when they are square or round, for instance—the engineers, not caring much one way or the other, would get to the point and solve it—correctly—in a matter of minutes.

There is nothing more that needs to be said about irrelevance: time for a coffee break, but, oh, there seem to be quite a lot of people with their hands up. Please give your names and speak clearly:

• Aristotle, here, wants to point out that, if the case a person is arguing is absurd, then every argument advanced in its favour is irrelevant.I93

• A Member of Parliament demonstrates the technique of tossing a blanket of irrelevant comments over a talkative general when it is time for bed:

General Dannatt has crossed an important line. He is playing a high-risk game. It is not appropriate to play party politics at this time. Dannatt should just get on with the job. After the conflict, if there are lessons to be learned, we should do so in a considered manner.I94

• A gentleman who prefers not to give his name offers an example of blather: “Did I steal the horse? Let me tell you, I have lived with horses all my life, and I have three children, and I am a qualified car mechanic . . .”

• A sympathetic acquaintance demonstrates misplaced emphasis: “So, other than that, Mrs. Lincoln, how did you enjoy the play?”I95

• Artemus Ward, entertainer (1834–1867), confides, “One of the principal features of my Entertainment is that it contains so many things that don’t have anything to do with it.”I96


Related entries:

Relevance, Distraction, Necessary and Sufficient, Reductio ad Absurdum, Shifting Ground, Straw Man, Time Fallacies.

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David Fleming
Dr David Fleming (2 January 1940 – 29 November 2010) was an economist, historian and writer, based in London. He was among the first to reveal the possibility of peak oil's approach and invented the influential TEQs scheme, designed to address this and climate change. He was also a significant figure in the development of the UK Green Party, the Transition Towns movement and the New Economics Foundation, as well as a Chairman of the Soil Association. His wide-ranging independent analysis culminated in two critically acclaimed books, Lean Logic and Surviving the Future. A film about his perspective and legacy - The Sequel: What Will Follow Our Troubled Civilisation? - was released in 2019, directed by BAFTA-winning director Peter Armstrong. For more information, including on Lean Logic, click the little globe below!

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