Kettle Logic

34 Kettle Logic

Andy Wible

The whole plea […] recalls vividly the defense offered by a man who was accused by his neighbor of having returned a kettle in a damaged condition. In the first place, he had returned the kettle undamaged; in the second place it already had holes in it when he borrowed it; and in the third place, he had never borrowed it at all. A complicated defense, but so much the better; if only one of these three lines of defense is recognized as valid, the man must be acquitted.

— Sigmund Freud, The Interpretation of Dreams

Kettle logic (KL) is a fallacy in which multiple contradictory premises are presented to support a point. As such, it is logically impossible for all of the premises to be true. Yogi Berra’s famous sayings are often contradictory. In the 1960s, while justifying why he didn’t go to Ruggeri’s restaurant anymore, he gives these two famous contradictory supporting claims committing a KL: “Nobody goes there anymore. It's too crowded.”

Formally, KL arguments are valid arguments, for it is impossible for contradictory premises to be true and the conclusion false. The problem is the principle of explosion, which shows that from a contradiction anything follows validly, and consequently all such arguments are trivial. Additionally, the argument cannot be sound for all of the premises cannot be true. It should be noted that paraconsistent logic has been developed to challenge the notion that such inconsistent arguments are trivial.

KL gets its name from Sigmund Freud in his book The Interpretation of Dreams. Freud relates the story of a man accused of returning a tea kettle with holes in it. The man defends himself saying: (1) he had returned the kettle undamaged, (2) the kettle already had holes in it, and (3) he never borrowed the kettle. Rather than helping his case by offering multiple supporting premises, the man actually undermines his case by making contradictory claims. The more he defends himself, the worse his credibility (Freud 1900, 101).

Freud believes KL is employed in dreams quite often. Contradictory beliefs are commonly offered, which give notice that one is in a dream. For example, in the embarrassment dream of being naked, the person feels shame for being naked and wants to run but for some reason cannot. Also, the people whom she feels embarrassed in front of are strangers whose faces are indefinite and they are indifferent to her nakedness. Such thinking is part of the “logic” of the dream world. She is caring about being laughed at by people who are unknown and don’t care. The reasons are not meant by the dreamer to be contradictory, but Freud believes they are.

Unfortunately, KL fallacies also abound in waking life in not so humorous ways. David Swanson, in his article “Cheney’s Kettle Logic,” points out that Vice President Dick Cheney gave the following defense of the administration’s decision to invade Iraq and the subsequent problems there. Cheney said that the intelligence used to justify invasion was sound and accurate, and that the fact it was flawed was the previous administration’s fault. When asked about the damage done to Iraq, he said that it was the Iraqis and not the allied forces who did the damage and that any invasion causes unfortunate horrific things to happen. He gives two KL fallacies to explain his administration’s decisions and the damage to Iraq.

Not all arguments that seem to have contradictory premises prove, upon closer examination, to be examples of KL. In the Yogi Berra example above, Berra is likely referring to a subset of people when he says “nobody.” The reference is likely to his group of friends who no longer go there due to the multitudes.

Freud’s dream example of KL may also not be fallacious. In the dream, the person may feel embarrassed at being naked in front of anyone, including strangers who don’t care. Or there could be a thought that the people appear indifferent but are really laughing on the inside.

Closer examination may also find the person is arguing in the alternative. As in KL, several inconsistent premises are given for the same conclusion, but it is not claimed that all of the premises are true. For example, a defense attorney might claim that his defendant didn’t cause the murder because he was at work during the crime, and even if he had been there, he is too short to have stabbed the victim in the head.

Often the problem in evaluating arguments that appear to be KLs is determining whether the arguer is claiming all of the premises are true. Even the man accused of borrowing the kettle might claim in his defense that he didn’t borrow the kettle or even if he had done it, he wouldn’t have borrowed a kettle with holes in it, and if he had borrowed a good kettle, he would not have returned it with holes. By using these hypotheticals, he is not claiming all of them are true.

Freud’s presentation of the tea kettle argument makes it clear that the man presents all of the premises as true. In real life and even in dreams, determining whether the arguer intends for all the considerations to be true, or whether additional information is missing, is much more difficult, but necessary in order to avoid the fallacy.